Types 92CT and 92CTP Temperature Regulators for Steam, Water, and Air

Transcription

1 Instruction Manual Form 5630 Types 92CT and 92CT April 2000 Types 92CT and 92CT Temperature Regulators for Steam, Water, and Air W7652 W7651 Figure 1. Type 92CT Temperature Regulator Figure 2. Type 92CT Temperature and ressure Limiting Regulator Introduction The Type 92CT is a pilot-operated, direct-acting temperature regulator that does not require an external power supply. The Type 92CT is used in heating applications where steam or hot water is normally the heating medium. With proper system sizing, the Type 92CT is accurate within 3% of the maximum temperature setpoint at steady state operating conditions. The key component of the Type 92CT is the thermostat of the Type 92T temperature pilot. The temperature pilot s thermostat consists of a spring opposed bellows-capillary-bulb system. This system contains a fill of an incompressible fluid at a pressure that is calibrated to the pilot's temperature control range to provide proportional control. The pilot body assembly (key 32, figure 13) is shipped from the factory in a separate box to prevent damage to the thermostat and must be assembled on the main body by the customer. The temperature pilot body assembly should be handled with care so as not to kink the capillary tube between the bulb and the pilot body. A kink in the capillary tube can make the temperature pilot inoperable. Temperature control can be a slow process because of the heat transfer characteristics of the system the temperature regulator is controlling. This is especially true of large tanks or jacketed kettles. Once steadystate operation (warm-up period) of the system is attained, the regulator may have to be re-adjusted to attain the required setpoint. Turn the adjusting knob of the temperature pilot until steady-state operation is attained. Install a temperature gauge in the process piping to facilitate setpoint adjustment. Since the Type 92CT is a temperature control regulator, it does not sense downstream pressure. During startup of a heating system, the downstream pressure could rise to full inlet pressure which can be above safe operating pressures. In these applications, it is (continued on page 3) D102699X012

2 Specifications Available Configurations Type 92CT: A Type 92C main valve with a Type 92T temperature control pilot. The Type 92T pilot only controls temperature. Type 92CT: A Type 92C main valve with a Type 92T temperature pilot and a Type 6392 pressure limiting pilot. The Type 6392 pilot prevents the downstream pressure from rising above its setpoint. Body Sizes And End Connection Styles (1) See table 1 Maximum Allowable Inlet and Outlet ressures (2) Cast Iron Constructions: 250 psig (17,2 bar) Steel Constructions: 300 psig (20,7 bar) Regulator ressure Drops (2) Minimum: 15 psi (1,0 bar) Maximum Operating: 150 psi (10,3 bar) for outlet pressure settings equal to or below 50 psig (3,4 bar); 200 psi (13,8 bar) for outlet pressure settings above 50 psig (3,4 bar) Maximum Emergency Cast Iron Construction: 250 psi (17,2 bar) Steel Construction: 300 psi (20,7 bar) Maximum Allowable Temperatures (2) Cast Iron Constructions: 406 F (208 C) Steel Constructions: 450 F (232 C) Type 92T Temperature Control Ranges See table 2 Type 6392 ressure Limiting ilot Control Ranges See table 3 Main Valve Orifice Sizes 1/2-inch Body: 9/16-inch (14,3 mm) 3/4 or 1-inch Body: (19,1 mm) (standard) or 9/16-inch (14,3 mm) (optional) Thermostat Connections See figure 15 Temperature Control Accuracy 3% of maximum scale at steady-state operation Limitation for Elastomer Main Valve Trim arts (2) 32 to 212 F (0 to 100 C) for use on water service only Type 92CT Downstream Control Line Connection 1/4-inch NT in Type 6392 pilot body ilot Vent Type 92T: Housing open to atmosphere Type 6392: 3/32-inch (2,4 mm) drilled hole Approximate Weight Type 92CT: 20 pounds (9,1 kg) Type 92CT: 24 pounds (11 kg) 1. End connections threaded to various national or international thread standards can usually be supplied. Contact the Fisher Sales Office or Sales Representative. 2. ressure/temperature limits in this instruction manual and any application codes must not be exceeded. Table 1. Main Valve Body Styles and End Connection Styles BODY SIZE, INCHES (DIN) 1/2 (15), 3/4 (20), or 1 (25) Cast Iron Body NT screwed END CONNECTION STYLE Steel Body NT screwed, 150 RF, 300 RF, or N 16/25/40 Table 3. Type 6392 ressure Limiting ilot Control Ranges OUTLET RESSURE RANGE, SIG (bar) SRING ART NUMBER SRING COLOR SIG (bar) ER TURN(1 ) 5 to 70 (0,34 to 4,8) 1E G reen 11 (0,76) 20 to 150 (1,4 to 10,3) 1E R ed 24 (1,7) 1. Change in outlet pressure per one complete turn of the pilot adjusting screw. Table 2. Type 92T Temperature Control Ranges (1) ILOTS TEMERATURE LABEL COLOR TEMERATURE CONTROL RANGE Y ellow 80 to 120 F (27 to 49 C) B lack 100 to 150 F (38 to 66 C) B lue 120 to 180 F (49 to 82 C) R ed 160 to 220 F (71 to 104 C) G reen 200 to 260 F (93 to 127 C) O range 260 to 320 F (127 to 160 C) 1. rovides 200 F (111 C) overheat protection (over control temperature range) up to a maximum temperature of 350 F (177 C). For example: 100 F (36 C) is protected up to 300 F (149 C) and 200 F (93 C) is protected up to a maximum of 350 F (177 C) to prevent damage to the thermostat assembly. 2

3 ADJUSTING KNOB BELLOWS TEMERATURE RANGE LABEL SRINGS SEAT THERMOSTAT BULB AND CAILLARY ASSEMBLY MAIN DIAHRAGM BLEED RESTRICTION INLET RESSURE LOADING RESSURE OUTLET RESSURE ATMOSHERIC RESSURE INCOMRESSIBLE FLUID FILL E0076 Figure 3. Type 92CT Temperature Regulator recommended to use a pressure regulator upstream of the temperature regulator to reduce the pressure to safe operating pressures. A popular alternative is to use a Type 92CT temperature and pressure limiting regulator. The Type 92CT regulator features a pressure limiting pilot that prevents downstream pressure from rising above the pressure pilot's setpoint. Using a pressure limiting pilot does not exclude the installation of ASME certified full flow relief valves as specified by local codes and regulations or system design. rincipal of Operation Type 92CT Temperature Regulator (figure 3) The pilot is operated by a contracting or expanding spring opposed bellows, according to the sensed temperature through a connected thermostat bulb and capillary assembly. The thermostat assembly is filled with an incompressible liquid, which expands or contracts in a linear response to the sensed temperature to provide proportional control. The main valve is spring closed. The pilot is held open by the force from its springs. Inlet steam passes through the pilot seat to increase loading pressure on the main valve diaphragm. The flow through the pilot is greater than the flow through the bleed restriction, increasing loading pressure and opening the main valve to provide more flow to the downstream system. As steam flow increases through the main valve, the downstream temperature increases and is sensed by the thermostat assembly. As temperature approaches the setpoint, the liquid fill in the thermostat assembly expands, causing the bellows to expand. The expanding bellows throttles the pilot which positions the main valve at a flow to control temperature. When set temperature is exceeded, the bellow assembly causes the pilot to close. Flow through the bleed restriction decreases loading pressure allowing the main valve to close. 3

4 RESSURE ADJUSTING SCREW TYE 6392 RESSURE LIMITING ILOT BELLOWS ADJUSTING KNOB TEMERATURE RANGE LABEL SRINGS SEAT THERMOSTAT BULB AND CAILLARY ASSEMBLY TYE 92T TEMERATURE ILOT INLET RESSURE LOADING RESSURE INTERMEDIATE RESSURE OUTLET RESSURE ATMOSHERIC RESSURE INCOMRESSIBLE FLUID FILL MAIN DIAHRAGM E0077 TYE 92C MAIN Figure 4. Type 92CT Temperature and ressure Limiting Regulator Temperature Adjustment Temperature adjustments are made by turning the green adjusting knob (see figure 3) on top of the pilot body assembly clockwise to decrease and counterclockwise to increase the temperature. The color-coded temperature range label shows the high and low ends of the pilot's temperature control range. Exact values depend on pressures and flow. To make final setpoint, use a temperature gauge to find the actual temperature. When making temperature adjustments, wear gloves or other protective gear. The temperature pilot may be hot. Type 92CT Temperature and ressure Limiting Regulator (figure 4) The Type 92T temperature pilot on the Type 92CT temperature regulator only controls temperature. To prevent overpressure during startup or large temperature disturbances the Type 92CT has a Type 6392 pressure limiting pilot to limit the downstream steam pressure to the Type 6392 pilot's pressure setpoint. The Type 6392 pressure limiting pilot measures downstream pressure. It interrupts the loading signal from the temperature pilot to the main valve to limit the maximum outlet pressure. The Type 92CT temperature and pressure regulator has two control spring options for the Type 6392 pilot, 5 to 70 psig (0,34 to 4,8 bar) and 20 to 150 psig (1,4 to 10,3 bar). Recalibration of the Type 92T temperature pilot may be necessary after the regulator reaches operating temperature. The temperature control range may shift downward 0.5 degrees for every 1 degree rise above ambient temperature. See the Temperature ilot Calibration procedure. ressure Adjustment ressure adjustments are made by turning the pressure adjusting screw clockwise to increase the pressure setting or counterclockwise to decrease the setting. See table 3 for psig (bar) per turn by spring range. Check the Type 92CT Startup section before making pressure adjustments. 4

5 SAFETY RELIEF INTERMEDIATE HOT WATER OUTLET INLET OUTLET T THERMOSTAT BULB HOT WATER TANK STRAINER TYE 92C TYE 92CT DRAIN COLD WATER INLET DRAIN DRI TRA FLOAT AND THERMOSTATIC STEAM TRA = ressure Gauge 19B0057 E0078 Figure 5. Typical Tank Heating Application Schematic T = Temperature Gauge Selecting Downstream Limiting ressure When selecting and adjusting the pressure pilot, make sure the set pressure meets downstream system design requirements. A pressure too high may exceed the system's pressure limits. Lower saturated steam pressures correspond to lower temperatures which can lengthen the heat transfer rate (time to heat) of the downstream system. Also, select a pressure limiting setting high enough to overcome the head (pressure) requirements of the condensate return system. Too low of a limiting pressure can cause condensate to back up into heat transfer equipment as the steam trap loses it minimum operating differential. ressure higher than downstream system requirements can create additional problems. Higher steam pressures have lower latent heat values which means more steam flow can be required to meet a demand. Therefore, raising the set pressure too high can cause the regulator to be undersized. Also, higher downstream steam pressure may produce greater amounts of flash steam across a steam trap. Condensate Return System Steam flow and condensate return system pressure can be difficult to determine and sometimes overlooked. The heat transfer equipment manufacturer should be able to provide the exact steam flow requirements and should be consulted in the design process. When replacing equipment in existing applications, contact the heat transfer equipment manufacturer and advise the serial number and model number to obtain steam flow information. When sizing the condensate return system, lb/hr of steam flow equals lb/hr of condensate produced. Therefore, the steam trap selected must pass the same amount of condensate flow as steam flow used in the steam system. Remember, mass is always conserved unless there are leaks in the heat transfer equipment. Inadequate condensate return system design can cause poor temperature control. Installation ersonal injury, equipment damage, or leakage due to escaping steam or bursting of pressure-containing parts may result if this regulator is overpressured or is installed where service conditions could exceed the limits given in the specifications and on the appropriate nameplate, or where conditions exceed any pressure or temperature ratings of the downstream piping components. To 5

6 STRAINER INLET TYE 92CT OUTLET DRI TRA INLET T OUTLET T THERMOSTAT BULB AIR INLET HEATED AIR OUTLET = ressure Gauge STEAM COIL T = Temperature Gauge DRAIN FLOAT AND THERMOSTATIC STEAM TRA 19B0058 E0079 Figure 6. Typical Air Heating or Air re-heating Application Schematic avoid such injury or damage, provide pressure-relieving or pressure-limiting devices to prevent service conditions from exceeding those limits. Type 92CT and 92CT installations should be checked for compliance with all applicable codes and regulations, such as the ANSI B ower iping standard or the ASME Boiler and ressure Vessel code, if applicable. Use qualified personnel when installing, operating, and maintaining Types 92CT and 92CT regulators. Make sure that there is no damage to or foreign material in the regulator and that all tubing and piping are clean and unobstructed. Install the regulator so that the flow direction matches the arrow found on the regulator body. Figures 5, 6, 7, and 8 show some typical Type 92CT and 92CT regulator applications. To prevent damage, do not lift or carry regulator or thermostat assembly by the capillary tubing. Since a clogged vent may cause improper regulator functioning, install the regulator so the Type 92T pilot housing and the Type 6392 pilot (if used) spring case vent remain clear and unobstructed. Damage to the thermostat assembly may release the fluid fill which contains approximately one cubic inch (16,4 cc) of kerosene or pentane as dictated by fill requirements. The temperature pilot body assembly should be handled with care so as not to kink the capillary tube between the bulb and the pilot body. A kink in the capillary tube can make the temperature pilot inoperable. To prevent condensate buildup, install the regulator so that condensate can drain from the body. For NT bodies apply compatible pipe compound to the male pipeline threads and for flanged bodies use acceptable flange gaskets between the regulator and pipe flanges. Then, using acceptable piping procedures, install the regulator into the pipeline. 6

7 = ressure Gauge T = Temperature Gauge INLET OUTLET T STRAINER TYE 92CT STRAINER STRAINER DRI TRA FLOAT AND THERMOSTATIC STEAM TRA 19B0059 E0080 OEN TANK Figure 7. Typical Open Tank Heating Application Schematic Type 92CT Temperature Regulator (figures 5, 6, 7, and 9) The following is a list of guidelines for installing the Type 92CT temperature regulator. 1. Follow proper steam piping practice when installing the Type 92CT in steam service. Install drip traps in inlet and outlet piping of the regulator as required. Install a strainer to prevent debris from damaging the regulator. Install a steam separator if the steam quality is poor (~90% or less). 2. Install a three valve bypass to allow for maintenance as shown in figure 9, if continuous service is required during maintenance. 3. Do not kink or crush the capillary tubing between the bulb and the temperature pilot. This can render the temperature pilot inoperable requiring replacement of the entire temperature pilot body assembly (key 32, figure 13). 4. The temperature pilot body assembly (key 32, figure 13) is shipped in a separate box to protect the capillary tubing. Install the temperature pilot body assembly (key 32) onto the pilot adaptor (key 31) as shown in figure 13 with the four cap screws (key 32m) and gasket (key 32k) provided in the box with the temperature pilot. The roll pin (key 31a) ensures proper alignment of the pilot body assembly and the pilot adaptor. 5. Various options of thermal bulb connection assemblies are available as shown in figure 15. Each assembly requires the bulb or thermowell of the thermostat assembly to be fully immersed in the process media. Failure to do so can result in poor temperature control. 6. All thermowells should be filled with heat transfer compound prior to placing the bulb in the thermowell. This will improve thermal contact by removing air space in the thermowell. Johnson Control s Heat Transfer Compound is recommended, but high temperature Neversieze or equivalent can also be used as long as the compound is compatible with the system's operating temperatures. 7. Install a temperature gauge in the process media. Locate the temperature gauge close to the thermostat bulb. The temperature is controlled where the thermostat bulb is located. 8. Inlet and outlet pressure gauges should be installed to monitor pressures on the system components. 9. rior to startup, ensure the inlet steam piping is free of debris and condensate by blowing off steam to a safe location through the main inlet strainer or other methods. Check the strainer, clean as required, and repeat until strainer is free of debris and condensate. 10. During startup, the regulator may respond with maximum flow and pressure to meet the heat demand of the unheated process fluid. The temperature pilot dial may require adjustment to obtain the required temperature setpoint after steady state conditions. 11. The temperature pilot has maximum and minimum temperature values with graduations to approximate 7

8 OUTLET INLET STRAINER TYE 92CT ROCESS FLUID OUT INLET T THERMOSTAT BULB SAFETY RELIEF VACUUM BREAKER STRAINER DRI TRA OUTLET T HEAT EXCHANGER STRAINER FLOAT AND THERMOSTATIC STEAM TRA 19B0229 E0081 CENTRIFUGAL UM TYE 92W = ressure Gauge T = Temperature Gauge Figure 8. Typical Shell and Tube Heat Exchanger Application Schematic startup setpoint. Use a temperature gauge to measure actual temperature and to adjust pilot setpoint after steady-state operation is attained. This will help prevent overheating. One method to reduce possible overheating is to start with the temperature setpoint below the desired setting and slowly increase the setpoint until the desired temperature is achieved. Type 92CT Temperature and ressure Limiting Regulator (figures 8 and 10) The following is a list of guidelines for installing the Type 92CT temperature and pressure limiting regulator. The guidelines listed for the Type 92CT temperature regulator also apply to the Type 92CT. The pilot supply and the regulator loading connections are normally factory installed as shown in figures 18 and 19. The downstream control line must be installed between the 1/4-inch NT pilot body connection and the downstream system as shown in figure Install the control line connection in a section of straight pipe several pipe diameters away from the regulator. Do not locate the control line connection in an elbow, swage, or other area where turbulence or abnormal velocities may occur. This reduces measurement of erratic pressures caused by piping components. Also make sure the control line is sloped away from the regulator so that condensate can drain into the pipeline away from the regulator. 2. Install a pressure gauge in the control line or near the regulator to aid in setting the outlet pressure. 3. Install inlet pressure gauge. 4. Install a shutoff valve (not a needle valve) in the control line to completely isolate the pilot during maintenance. A needle valve can restrict the small bleed flow in the control line effecting pressure control. 5. Review the Type 92CT Startup section before adjusting the Type 6392 set pressure. (The temperature control loop must be open to supply pressure to the Type 6392 pilot and allow set pressure adjustment.) Startup Type 92CT Startup (figure 9) The maximum inlet pressure for a specific construction is stamped on the main valve nameplate. Use pressure gauges to monitor upstream and downstream pressures and a temperature gauge to monitor temperature. Do not exceed the system component pressure and temperature ratings. To avoid personal injury, introduce steam into the system by slowly opening the 8

9 INLET T THERMOSTAT BULB STRAINER DRAIN TYE 92CT = ressure Gauge T = Temperature Gauge E0085 DRI TRA Figure 9. Typical Type 92CT Startup Schematic isolation block valves. This will reduce the effects of destructive waterhammer. Make sure upstream and downstream condensate removal is operational. Condensate can cause erratic temperature control from poor trap sizing. ersonal injury and/or dangerous equipment damage can occur from water hammer caused by movement of condensate. re-startup Guidelines 1. Make sure the thermostat bulb or thermowell is fully immersed in the process media. Large tanks should have adequate circulation and mixing to ensure uniform tank temperature. 2. To prevent condensate from flooding heat transfer surfaces, make sure the condensate removal system is installed and sized adequately. 3. The heat transfer equipment should be sized with an approach temperature suitable for the process. The approach temperature is the difference between steam temperature and the set temperature of the regulator. As a general rule, an approach temperature of 30 F (17 C) is typical for heating water. 4. A vacuum breaker should be installed to prevent a vacuum on the steam side of the heat transfer equipment (if required). 5. Ensure a temperature gauge is installed in the process fluid and it is easily viewed from the temperature pilot's adjusting knob. The temperature range label on the adjusting knob shows the approximate high and low ends of the temperature range and should only be used as a guide during startup. Make sure the temperature gauge is installed near the thermostat bulb because the bulb is the feedback monitor for process media temperature control. Startup rocedure (figure 9) To put the regulator into operation: 1. Open all drains in the system (located on strainers, drip legs, and heat exchangers) to allow condensate to drain. This can prevent dangerous water hammer upon system startup. 2. For new system startup, perform a blowdown of the inlet piping to prevent damage to the regulator. Make sure the drains are piped to a safe location. Close the upstream and downstream block valves. Open the strainer drain valve located upstream of the regulator. Slowly open the upstream block valve for several seconds allowing steam to blow-off through the strainer's drain valve. Close the upstream block valve. Remove the strainer basket. Inspect, clean, and replace the strainer basket. Repeat this step until the strainer basket is free of debris. For existing systems that are being re-started after seasonal or periodic shutdowns, make sure the regulator, heat transfer equipment, and steam traps are clean and free of condensate. These components should be cleaned and inspected so that they are free of scale, rust, debris, and condensate that accumulated during shutdown periods. 9

10 INLET STRAINER OUTLET DRAIN TYE 92CT T THERMOSTAT BULB = ressure Gauge E0086 DRI TRA T = Temperature Gauge Figure 10. Typical Type 92CT Startup Schematic 3. Open the downstream block valve. 4. Slowly open the upstream block valve while monitoring the temperature gauge and system pressures. 5. If a bypass line is used, slowly close the bypass line block valve as the upstream block valve (mentioned in step 4) is being opened. 6. Check the temperature after waiting for steady state to be established. If necessary, change the temperature setpoint and wait for steady state. Type 92CT Startup (figure 10) The Type 92CT temperature and pressure limiting regulator requires pressure as well as temperature setting to startup. Refer to the Type 92CT Startup section for temperature setting and the startup guidelines. ressure setting steps are outlined in the ressure Setting Adjustment section.! WARNING ERSONAL INJURY COULD RESULT FROM IMROER ADJUSTMENT. REFER TO STARTU SECTION OF RODUCT INSTRUCTION MANUAL. Fisher Controls The warning tag above is attached to the adjusting screw of the Type 6392 pressure limiting pilot on a Type 92CT temperature and pressure limiting regulator. Each pressure pilot is factory-set at approximately the lowest spring range value. Check the spring range to make sure it is correct for the application. (The pressure range is stamped on the pressure pilot nameplate.) Final pressure adjustment may be necessary after steady-state operation is attained for best temperature control. The pressure pilot must not be set above allowable system pressure to prevent dangerous pressures. ressure Setting Adjustment 1. Adjust the temperature pilot several degrees below its desired set point. This will cause the temperature pilot to open, providing loading pressure (see figure 4) to the Type 6392 pressure limiting pilot. 2. Adjust the Type 6392 to its desired set pressure by turning the adjusting screw while viewing a downstream pressure gauge. See table 3 for psig (bar) per turn information. 3. Raise the temperature pilot to its desired setpoint and monitor the system operation. 4. Repeat as necessary until steady state operation is attained at the desired temperature and pressure. 10

11 Shutdown To shutdown the temperature system Open the drains (located on strainers, drip legs, and heat exchangers) to remove condensate. Do not open drains of pressurized piping unless outlet piping of each drain is piped to a safe location. To take the regulator out of operation 1. If a bypass line is used, slowly open the bypass line block valve while monitoring the downstream pressure and temperature. 2. Close the upstream block valve. 3. Close the downstream block valve. 4. Close the control line shutoff valve, if pressure limiting pilot is used. 5. Open all drain valves as needed to release all pressure. Maintenance Regulator parts are subject to normal wear and must be inspected periodically and replaced as necessary. The frequency of inspection and replacement depends upon the severity of service conditions and upon applicable Federal, state, and local codes and regulations. Replacing Diaphragm and Stem Assembly 1. Remove all tubing connections from the main valve (figures 16, 17, 18, and 19). 2. Remove the cap screws (key 12) and the diaphragm flange (key 2). Lift out the upper diaphragm gasket (key 9), the diaphragms (key 8), the lower diaphragm gasket, and for constructions, the diaphragm ring (key 15), and the diaphragm gasket (key 9). 3. Lift out the stem assembly (key 11) consisting of the pusher plate and the stem. Check that the pitot tube (key 10) is clear and free of obstructions. Clean the parts. Check for wear, scratches, nicks and other damage, and replace parts as necessary. 4. Install the stem assembly (key 11) in the stem guide bushing (key 6). lace one diaphragm gasket (key 9) in the regulator body (key 1). For constructions, place the diaphragm ring (key 15) and another diaphragm gasket (key 9) on top of the first gasket. For all constructions, place the two molded metal diaphragms (key 8) with the raised circle up, another diaphragm gasket, and the diaphragm flange (key 2) on the body. Insert and tighten the cap screws (key 12). 5. Reconnect all tubing connections to the main valve (figures 16, 17, 18, and 19) Replacing Valve lug and Orifice Avoid personal injury or property damage from release of pressure, high temperature steam, or other process fluid. Before starting disassembly: Isolate the regulator from the process pressure. Vent all pressures from the main valve and pilot(s). Allow the regulator to cool to a safe temperature. This section contains separate maintenance procedures for the Type 92C main valve, the Type 92T temperature pilot, and the Type 6392 pressure limiting pilot. Type 92C Main Valve (figure 11) The regulator may remain in the pipeline during maintenance procedures. The pilot(s) may remain on the main valve during maintenance. 1. Remove the valve plug guide (key 5). 2. Remove the valve plug (key 4) and the valve plug spring (key 7). Inspect the valve plug seating surface for nicks or scratches. Replace as necessary. 3. Inspect the orifice (key 3) and seating surface for nicks and scratches. Replace if necessary. 4. Clean the valve plug guide, the valve plug, the valve plug spring, and the orifice (keys 5, 4, 7, and 3, respectively). 5. Lubricate the orifice threads and body metal seal surface. Then, being careful not to damage the seating surface, thread the orifice (key 3) into the regulator body (key 1). 6. lace the valve plug spring (key 7) into the valve plug guide (key 5). Then slide the valve plug (key 4) over the spring and into the valve plug guide. 7. Apply sealant to the valve plug guide threads and body metal seal surface, and screw the valve plug guide (key 5) with attached parts into the regulator body (key 1). 11

12 Type 92T Temperature ilot (figures 13 and 14) arts Inspection and Replacement Use the following procedure to inspect the seat and lower plug of the stem cartridge assembly for wear, wire drawing, or scale buildup. To inspect the stem cartridge, disassemble the thermostat assembly by unscrewing the 1-1/8-inch locknut located below the green adjusting knob. Remove the stem cartridge assembly and clean or replace as required. 1. Unscrew the lock nut (key 32c). Carefully lift off the subassembly including the adjusting knob (key 32a), thermostat bulb, and capillary tubing. Set it aside (do not disassemble). 2. ull out the head and guide assembly (key 32f) and the copper head guide gasket (key 32g). 3. Unscrew and remove the seat (key 32h) and seat gasket (key 32j) using a thin walled 1/2-inch extended socket. 4. Apply a high temperature thread sealant to the threads of the new seat (key 32h). 5. lace the new seat (key 32h) and seat gasket (key 32j) in the temperature pilot body assembly (key 32) and tighten the new seat. 6. lace a new copper head guide gasket (key 32g) into the temperature pilot body assembly (key 32). 7. lace a new head and guide assembly (key 32f), with the ball plug down, into the temperature pilot body assembly (key 32). 8. Carefully replace the subassembly which includes the adjusting knob (key 32a), thermostat bulb, and capillary tubing. Tighten the lock nut (key 32c). Screen To inspect the temperature pilot screen, remove the screen plug (key 31b) from the temperature pilot adaptor (key 31). Inspect the screen (key 31c) and clean or replace with new screen. Replace the screen plug (key 31b) and tighten. ilot Body Assembly Replacement 1. Follow the directions in the Shutdown section and remove the thermostat bulb from the process fluid or thermowell. 2. Remove the four cap screws (key 32m) connecting the temperature pilot body assembly (key 32) to the temperature pilot adaptor (key 31). 3. Lift off the temperature pilot body assembly (key 32) and remove the gasket (key 32k). 4. lace the new gasket (key 32k) on top of the temperature pilot adaptor (key 31). Check that the gasket is aligned with the roll pin (key 31a) and the hole pattern in the temperature pilot adaptor. 5. lace the new temperature pilot body assembly (key 32) on top of the gasket (key 32K) and temperature pilot adaptor (key 31). Make sure the temperature pilot body assembly (key 32) is aligned with the pilot adaptor (key 31) holes and roll pin (key 31a). The arrows on the side of the pilot body assembly and the pilot adaptor should be aligned when the pilot body is in the correct position. 6. Insert and tighten the four cap screws (key 32m). 7. Install the thermostat bulb in the process fluid or thermowell and follow directions in the Startup section. Temperature ilot Calibration Calibration may be required if the regulator is controlling the temperature smoothly but the adjusting knob reaches its travel stop before the desired temperature is achieved. Follow these steps to readjust the knob: 1. Turn the adjusting knob (key 32a) to its travel stop closest to the desired temperature. 2. Loosen the set screw (key 32b) on the adjusting knob (key 32a). Be careful not to move the knob up or down against the case tube because the pointer could rub against the knob or slide under the travel stop. If the pointer rubs against the knob during normal operation, loosen the set screw and raise the adjusting knob 1/8-inch. Tighten the set screw. If the pointer slides under the travel stop during normal operation, loosen the set screw and lower the adjusting knob 1/8-inch. Tighten the set screw. 3. Turn the adjusting knob (key 32a) away from the travel stop approximately 1/4-inch as measured on the label. This will correspond to a temperature adjustment of approximately 5 F (3 C). Greater adjustment will reduce the operating life of the pilot. 4. Tighten the set screw (key 32b) in the adjusting knob. 12

13 Type 6392 ressure Limiting ilot (figure 12) erform this procedure if inspecting, cleaning, or replacing any pilot parts. Key numbers refer to figure 12. All pilot maintenance may be performed with the pilot body (key 1) attached to the main valve. 1. Loosen the jam nut (key 15), and turn the adjusting screw (key 16) counterclockwise until all compression is removed from the control spring (key 13). 2. To replace diaphragm, remove the cap screws (key 17), spring case (key 2), control spring, and upper spring seat (key 14) from the body. Remove the lower spring seat (key 9), the diaphragms (key 7), and the diaphragm gasket (key 8) from the body. Lift out the stem assembly (key 6) consisting of the stem and the pusher plate. Clean the 1/16-inch (1,6 mm) diameter pilot bleed hole. Clean and replace parts as necessary, and assemble the stem assembly, the gasket, the diaphragm, and the spring seat in the order shown in figure Install the control spring (key 13) and spring case (key 2). Insert and tighten the cap screws (key 17). Lubricate the adjusting screw (key 16) tip and threads then thread it into the spring case. 4. To replace trim, unscrew the valve plug guide (key 5). Remove the strainer screen (key 12), the valve plug (key 4), the valve plug cap (key 26), and the valve plug spring (key 11). Inspect the orifice (key 3). Clean and replace parts as necessary. Apply lubricant to the orifice threads and metal body seal surface, then screw the seat ring into place. 5. lace the valve plug spring (key 11) into the valve plug guide (key 5). Insert the valve plug cap (key 26) into the valve plug (key 4), and then slide both parts over the spring and into the valve plug guide. lace the strainer screen (key 12) onto the valve plug guide. Apply sealant to the valve plug guide threads and metal body seal surface, then screw the valve plug guide with the attached parts into the pilot body (key 1). Troubleshooting Temperature Control The following is a list of possible causes if the regulator does not reach set temperature: 1. The thermostat bulb or thermowell may not be fully immersed in the process fluid. 2. The heat exchanger surfaces may be fouled or flooded with condensate. 3. The steam trap may be operating below its minimum pressure differential. 4. The capillary tubing may be kinked or broken. 5. A failed bellows may have caused the thermostat bulb to loose its fill. 6. Inlet process temperature may have dropped below acceptable heat exchanger ratings. 7. The tank may not be mixed adequately. 8. A vacuum breaker may need to be installed on the heat exchanger allowing condensate buildup. 9. There is no thermowell compound between the thermowell and the thermostat bulb. 10. The regulator may be operating below its minimum pressure differential. 11. The regulator may be undersized and will not pass the required flow. The following is a list of possible causes if the control temperature cycles around the set temperature: 1. The condensate control system may not be operating properly. 2. Inlet process temperature may be swinging above or below the acceptable levels of the heat exchanger's ratings. 3. The tank may not be mixed adequately. 4. Heat exchange surfaces may be fouled or flooded with condensate. 5. A vacuum breaker may need to be installed on the heat exchanger. 6. There is no thermowell compound between the thermowell and the thermostat bulb. 7. Regulator is operating below its minimum pressure differential. 8. The regulator is oversized. arts Ordering When corresponding with your Fisher Sales Office or Sales Representative about this regulator, specify the serial number found on the regulator nameplate. When ordering replacement parts or parts kits, specify the complete 11-character part numbers found in the following parts list. 13

14 STEEL OR STAINLESS STEEL CONTRUCTION 26A1536-A E0099 CAST IRON CONTRUCTION Figure 11. Types 92CT and 92CT Main Valve Assembly arts List Type 92C Main Valve (figure 11) Key Description art Number Key Description art Number arts Kit (includes keys 3, 4, 7, 8, and 9) 9/16-inch (14,3 mm) orifice orifice (19,1 mm) R92CX R92CX Body Assembly w/bushing (see key 6 for bushing) Type 92CT Body Cast Iron NT 1/2-inch 38B9890X012 38B9891X012 1-inch 38B9892X012 Steel NT 1/2-inch 38B9887X012 38B9888X012 1-inch 38B9889X RF 1/2-inch 19B0048X012 19B0048X022 1-inch 19B0048X RF 1/2-inch 19B0048X042 19B0048X052 1-inch 19B0048X062 16/25/40 RF 1/2-inch 19B0048X072 19B0048X082 1-inch 19B0048X092 1 Body Assembly w/bushing (continued) Type 92CT Body Cast Iron NT 1/2-inch 1-inch Steel NT 1/2-inch 1-inch 150 RF 1/2-inch 1-inch 300 RF 1/2-inch 1-inch 16/25/40 RF 1/2-inch 1-inch 2 Diaphragm Flange Cast Iron Steel 36A1539X012 36A1540X012 36A1541X012 36A1542X012 36A1543X012 36A1544X012 14B3428X012 14B3428X022 19A5459X012 14B3428X032 14B3428X042 14B0037X012 14B3428X052 14B3428X062 14B3428X072 26A1533X012 26A1534X012 14

15 16A1520-b E0100 Figure 12. Type 6392 ressure Limiting ilot Assembly Type 6392 ressure Limiting ilot (figure 12) Key Description art Number 3 Orifice, hardened 416 stainless Metal Seat For 1/2-inch body 9/16-inch (14,3 mm) 16A1529X012 For or 1-inch body 9/16-inch (14,3 mm) 16A1529X012 (19,1 mm) (standard) 16A1528X012 Composition Seat, 9/16-inch (14,3 mm) only 1E Valve lug for Metal Seat, hardened 416 stainless 1E Disk Holder Assembly for Composition Seat 1E3996X Valve lug Guide (for cast iron body) 1E stainless (for body) 1E Stem Guide Bushing, hardened 416 stainless (included in key 1) For cast iron body 1E For body 16A1530X012 7 Valve lug Spring, stainless 1E * Diaphragm, stainless (2 required) 1E * Diaphragm Gasket, (2 required for cast iron body; 3 required for body) 16A1526X itot Tube, copper For cast iron body 16A1525X012 For body 1E Stem Assembly, 416 stainless 16A1524X Cap Screw, plated (8 required) For cast iron body 1A For body 1A Nameplate, aluminum Drive Screw, stainless (2 required) 1A Diaphragm Ring, ( body only) 16A1531X012 Key Description art Number arts Kit (includes keys 3, 4, 7, 8, 11, and 12) R6392X ilot Body Cast iron 26A1518X012 Steel 26A1517X012 2 Spring Case Cast iron 2E Steel 2J Orifice, hardened 416 stainless 16A1511X012 4 Valve lug, hardened 416 stainless 16A1516X012 5 Valve lug Guide, hardened 416 stainless 1E Stem Assembly, 416 stainless 16A1515X012 7 Diaphragm, stainless (2 required) 1E * Diaphragm Gasket 1E3931X Lower Spring Seat, aluminum 1E Stem Guide Bushing, 416 stainless 1E Valve lug Spring, stainless 1E Strainer Screen, stainless 16A1512X Control Spring, zinc plated 5 to 70 psig (0,34 to 4,8 bar), green 1E to 150 psig (1,4 to 10,3 bar), red 1E Upper Spring Seat, zinc plated 1B Jam Nut, plated 1A Adjusting Screw, plated 1E Cap Screw, plated (6 required) For cast iron body 1A For body 1A Nameplate, aluminum Drive Screw, stainless (2 required) 1A Valve lug Cap, hardened 416 stainless 16A1549X012 15

16 CAILLARY TUBING UNION TEMERATURE RANGE LABEL TRAVEL STO THERMOSTAT BULB 29B0052-a E0087 EXTERIOR ASSEMBLY 19B E0088 INTERIOR ASSEMBLY Figure 13. Type 92T Temperature ilot Assembly 19B HEAD AND GUIDE ASSEMBLY (KEY 32f) HEAD GUIDE GASKET (KEY 32g) CA SCREW (KEY 32m) SEAT (KEY 32h) SEAT GASKET (KEY 32j) GASKET (KEY 32k) 18B3532 E0089 SCREEN (KEY 31c) Figure 14. Type 92T Temperature ilot Spare arts Kit 16

17 5/8-inch (16 mm) 8-inches (20 cm) (19 mm) 5-es (15 cm) NT LAIN COER BULB UNION NUT ON COER BULB WITH STAINLESS STEEL WELL (STANDARD) 5-7/32-inches (13 cm) 18-inches (46 cm) (19 mm) (19 mm) NT NT UNION NUT ON COER BULB (STANDARD) UNION NUT ON COER BULB WITH BRASS EXTENSION WELL 5-es (14 cm) 18-inches (46 cm) (19 mm) (19 mm) NT NT UNION NUT ON COER BULB WITH BRASS WELL UNION NUT ON COER BULB WITH STAINLESS STEEL EXTENSION WELL E0082 Figure 15. Thermostat Connection Options. Thermostats are available with a standard 8 feet (2,44 m) armored capillary or an optional 15 feet (4,57 m) armored capillary. Each thermostat has an overheat protection bellows that protects against overheating up to 200 F (93 C) over setpoint, provided the system temperature does not exceed 350 F (177 C). Note: thermostatic elements are available upon request. Type 92T ilot (figures 13, 14, and 15) Key Description art Number Mounting arts (figures 16, 17, 18, and 19) Key Description art Number arts Kit, see figure 14 18B3532X012 (Includes: 31c, 32f, 32g, 32h, 32j, 32k, and 32m) Replacement Thermowell, key 32d 5- Standard Length 18-inch Extended Length 19B0952X012 19B0952X022 19B0953X012 19B0953X ilot Adapter, Cast iron 18B3510X012 Includes: 31a - Roll pin, 31b - Screen plug, and 31c - Screen 32 ilot Body Assembly See table 4 Includes: 32a - Adjusting knob 32g - Head guide gasket 32b - Set screw 32h - Seat 32c - Lock nut 32j - Seat gasket 32d - Thermowell 32k - Gasket 32f - Head and guide 32m - Cap screw assembly (4 required) 23 Bleed Restriction (Type 92CT only) 24 Tubing (2 required for Type 92CT and 1 Required for Type 92CT) Copper and brass 26 ipe Nipple (1 required for Type 92CT and 2 required for Type 92CT) Copper and brass 27 Hex ipe Bushing Copper and brass 28 Tee Connector (Type 92CT only) Copper and brass 29 Connector (2 required for Type 92CT and 1 required for Type 92CT) Copper and brass 30 Elbow Copper and brass 1K9484X0012 1K9484X W W 1N N5824X0022 1C C3790X A6002X312 15A6002X712 15A6002X212 15A6002X642 15A6002X172 15A6002X632 17

18 29B0050 E0090 Figure 16. Type 92CT Temperature Regulator Assembly with Temperature ilot Installed in the Up osition 29B0052 E0092 Figure 17. Type 92CT Temperature Regulator Assembly with Temperature ilot Installed in the Down osition 18

19 29B0052 E0092 Figure 18. Type 92CT Temperature and ressure Limiting Regulator Assembly with the ilots Installed in the Up osition 29B0053 E0093 Figure 19. Type 92CT Temperature and ressure Limiting Regulator Assembly with the ilots Installed in the Down osition 19

20 Table 4. Type 92CT ilot Body Assembly (key 32) art Numbers CAILLARY LENGTH 8 feet (2,44 m) 15 feet (4,57 m) THERMOSTAT BULB MATERIAL CAILLARY FITTING TYE Angle Angle, Angle, Angle, Angle Angle, Angle, Angle Angle, Angle, Angle, Angle Angle, Angle, THERMOSTAT WELL MATERIAL 80 to 120 F (27 to 49 C) Yellow TEMERATURE RANGE AND TEMERATURE RANGE LABEL COLOR 100 to 150 F (36 to 66 C) Black 120 to 180 F (49 to 82 C) Blue 160 to 220 F (71 to 104 C) Red 200 to 260 F (93 to 127 C) Green 260 to 320 F (127 to 160 C) Orange 18B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X B3512X93 2 Extended brass 18B3512X B3512X B3512X B3512X B3512X B3512X94 2 Extended stainless 18B3512X102 18B3512X B3512X B3512X B3512X B3512X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X B3513X93 2 Extended stainless 18B3513X102 18B3513X B3513X B3513X B3513X B3513X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X B3514X93 2 Extended brass 18B3514X B3514X B3514X B3514X B3514X B3514X94 2 Extended stainless 18B3514X102 18B3514X B3514X B3514X B3514X B3514X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X B3515X93 2 Extended stainless 18B3515X102 18B3515X B3515X B3515X B3515X B3515X95 2 Fisher is a mark owned by Fisher Controls International, Inc., a business of Emerson rocess Management. The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their respective owners. The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. We reserve the right to modify or improve the designs or specifications of such products at any time without notice. Fisher does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Fisher product remains solely with the purchaser. For information, contact Fisher: Marshalltown, Iowa USA McKinney, Texas USA Gallardon, France Castel Maggiore (BO), Italy Sao aulo Brazil Singapore Fisher Controls International, Inc., 1999, 2000; All Rights Reserved