WARNING IMPORTANT

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1 H September, 2015 INSTALLATION/SETUP INSTRUCTIONS Electronic Mild Temperature Thermostat gas-fired duct furnace/make-up air units Model Series: D, H, I, & O Application The Electronic Mild Temperature Thermostat option is used to automatically disable the gas controls when the inlet air temperature reaches the desired setpoint to prevent the furnace from excessively cycling at mild outside air temperature conditions. The option uses a Johnson Controls System 350 on/off electronic temperature control with single-pole, double-throw relay output and LED indication. Figure 1.1 Mild Temperature Thermostat WARNING 1. Disconnect power supply before making wiring connections to prevent electrical shock and equipment damage. 2. All units must be wired strictly in accordance with wiring diagram furnished with the unit. Any wiring different from the wiring diagram could result in a hazard to persons and property. 3. All wiring must be done with a wiring material having a remperature rating of at least 105 C. Components For Model Sizes (Digits 4-6) : AA-1C Electronic Temperature Control Module F range, 1 to 30 F differential SET189A-600R Inlet Air Temp Sensor (factory installed on outdoor units, field installed on indoor units) For Model Sizes (Digits 4-6) : Same as above, but adds S350AA-1C Electronic Stage Module - 1 to 30 F differential The Electronic Temperature Control operates on 24VAC and supplies a SPDT relay output based on a temperature change against the setpoint. When the temperature rises above the setpoint, the relay contacts open. An LED on the front panel labeled ON illuminates to indicate when the relay is energized. There are two adjustable features on the controller, the setpoint and differential, which are covered later in these instructions. The S350 Electronic Stage Module provides SPDT relay output when the differential from the has been satisfied. An LED on the front panel labeled ON illuminates to indicate when the relay is energized. There are two adjustable features on the controller, the offset and differential, which are covered later in these instructions. Wiring This option is prewired at the factory. Additional wiring is not required. In the event that additional wiring is necessary, installation of wiring must conform with local building codes, or in the absence of local codes, of the National Electric Code ANSI/NFPA 70 - Latest Edition. Unit must be electrically grounded in conformance to this code. In Canada, wiring must comply with CSA C22.1, Part 1, Electrical Code. IMPORTANT The use of this manual is specifically intended for a qualified installation and service agency. All installation and service of these units must be performed by a qualified installation and service agency. Modine manuals may contain excerpts from component supplier literature adapted for Modine products. Any accompanying component supplier literature is for general information. THIS MANUAL IS THE PROPERTY OF THE OWNER. PLEASE BE SURE TO LEAVE IT WITH THE OWNER WHEN YOU LEAVE THE JOB.

2 INSTALLATION/SETUP Electronic Mild Temperature Thermostat Sensor Mounting (Indoor Units Only) This section applies ONLY to indoor models ( D and I model series units). Outdoor models ( H and O model series) already have the sensor mounted on the unit inlet. 1. The unit comes with the sensor prewired, with the sensor and wire coiled in the blower section for shipping purposes. Extend the sensor/wire outside the blower casing as shown in Figure 2.1. Figure 2.1 Sensor Installation on Indoor Units EXTEND SENSOR CABLE THROUGH BUSHING IN CASING Definitions Before proceeding to the Settings Adjustments section, review the following definitions and refer to Figure 2.3. Setpoint Setpoint is the temperature at which the relay will deenergize. When the temperature at the sensor rises above the setpoint (i.e. mild outside air temperature conditions), the relay will be de-energized, the contacts will open, and the gas controls will be disabled. Differential Differential is the change in sensor temperature between energization and de-energization of the relay. When the temperature falls below the setpoint by the number of degrees of differential, the relay will be energized, the contacts will close, and the gas controls will be enabled. Offset This adjustment only applies to units with the S350 Electronic Stage Module. The offset adjustment determines the amount of offset from the setpoint that the S350 s relay will de-energize. When the temperature sensed rises above the Setpoint MINUS the S350 Offset, the relay will be de-energized, the contacts will open, and the gas controls for Furnace #3 will be disabled. 2. The sensor wire included provides enough length to install the sensor bracket approximately 2 feet from the inlet end of the unit. If additional length is required, please refer to the Wiring section. 3. Drill a single 1-1/4" diameter hole in the outside air intake duct to mount the sensor bracket. 4. Before mounting the bracket, secure the sensor and sensor wire to the bracket with the cable ties provided. Refer to Figure Insert the bracket into the hole drilled in step 3 and secure to the duct with the screws provided. Figure 2.2 Sensor Installation on Indoor Units DUCTWORK BY OTHERS Note that for the Setpoint, Differential, and Offset to work properly for the Mild Temperature Thermostat application, the mode must be set to Heating. Refer to the section Settings Adjustments for instructions. Figure 2.3 Mild Temp Stat Control Descriptions (+) TEMPERATURE ( ) OFF ON OFFSET S350 OFF ON CLOSE-UP VIEW OF SENSOR/BRACKET BEFORE INSTALLED IN DUCTWORK

3 INSTALLATION/SETUP Electronic Mild Temperature Thermostat Settings Determination Before proceeding to the adjustment of settings on the and, if applicable, the S350, review the following sections to determine the suggested settings for the unit as configured. There are two ways to determine the settings: 1) Use the Table Method with Tables on this page, based on the Model Size of the unit, or 2) Use the Calculation Method on pages 4 through 6 to derive the settings for conditions not shown in Tables 3.1 through 3.4. After using either method to determine the correct settings, please proceed to the Settings Adjustment Section on page 7 for instructions. Table Method If the job conditions are different than shown in Tables 3.1 through 3.4, proceed to the Calculation Method on pages 4 through 6. Model Sizes (Digit 4-6) = 75 through 400 For Model Sizes (Digit 4-6) = 75 through 400, the discharge air temperature setpoint is required. With that information, Table 3.1 can be used to determine the suggested Setpoint on the. Example: What is the Setpoint for a 350 sized unit, 100 F air temperature rise, -25 F outside air temperature, and a discharge air setpoint of 75 F? Answer: The only relevant information is the discharge air temperature setpoint, in this case, 75 F. From Table 3.1, the suggested Setpoint on the is 70 F. Table 3.1 Setpoint for Model Sizes (Digit 4-6) = 75 to 400 Temp Rise Discharge Air Temp ( F) ( F) All Model Sizes (Digit 4-6) = 500 through 800 For Model Sizes (Digit 4-6) = 500 through 800, the discharge air temperature setpoint is required, along with the unit design air temperature rise. Table 3.2 can then be used to determine the suggested Setpoint on the. Example: What is the Setpoint for a 600 sized unit, 100 F air temperature rise, -20 F outside air temperature, and a discharge air setpoint of 80 F? Answer: The only information that is relevant is the discharge air temperature setpoint of 80 F and the air temperature rise of 100 F. From Table 3.2, the suggested Setpoint on the is 35 F. Table 3.2 Setpoint for Model Sizes = 500 to 800 Temp Rise Discharge Air Temp ( F) ( F) Model Sizes (Digit 4-6) = 840 through 960 For Model Sizes (Digit 4-6) = 840 through 960, the discharge air temperature setpoint is required, along with the unit design air temperature rise. Table 3.3 can then be used to determine the suggested Setpoint on the and Table 3.4 used to determine the Offset on the S350. Example: What is the Setpoint () and Offset (S350) for a 960 sized unit, 70 F air temperature rise, 0 F outside air temperature, and a discharge air setpoint of 70 F? Answer: The only relevant information is the discharge air temperature setpoint of 70 F and the air temperature rise of 70 F. From Table 3.3, the suggested Setpoint on the is 52 F. From Table 3.4, the S350 Offset is 24 F Table 3.3 Setpoint, Model Sizes 840 to 960 Temp Rise Discharge Temp ( F) ( F) Table 3.4 S350 Offset, Model Sizes 840 to 960 Temp Rise ( F) Offset for All Discharge Temps ( F) 120 to

4 30 F INSTALLATION/SETUP Electronic Mild Temperature Thermostat Calculation Method If the job conditions are different than shown in Tables 3.1 through 3.4, the following Calculation Method can be used to determine the setpoints. If the Table Method from page 3 was used to determine the correct settings, proceed to page 7 for instructions on adjusting the settings. Settings for Model Sizes (Digit 4-6) = 75 through 400 For these units, the Setpoint and Differential must be set on the controller. The Setpoint is typically set as follows: Setpoint = Discharge Temperature - 5F The Differential is typically set at 3 F to avoid nuisance switching. Example: What are the settings for a unit with a discharge temperature setpoint of 70 F? Setpoint = 70 F 5 F = 65 F Differential = 3 F Referring back to the Definitions, the following is the sequence of operation for the control: o o Once the outside air temperature falls to 62 F (65 F Setpoint - 3 F Differential), the gas controls will be enabled. Once the gas controls are enabled, they will remain enabled until the temperature rises above the 65 F Setpoint. Figure 4.1 Mild Temperature Thermostat Settings for Model Sizes (Digit 4-6) 75 to 400 JOHNSON AA-1C SHOWN WITH FRONT COVER REMOVED (CONTROL IS LOCATED IN THE BLOWER ELECTRICAL COMPARTMENT) JUMPER POSITION HEATING COM N.O. FURNACE #1 FACTORY WIRING

5 30 F INSTALLATION/SETUP Electronic Mild Temperature Thermostat Calculation Method (continued) Settings for Model Sizes (Digit 4-6) = 500 through 800 For these units, the Setpoint and Differential must be set on the controller. The Setpoint is typically set as follows: Setpoint = Discharge Temperature (0.5 x T) + 5 F The Differential is typically set at 3 F to avoid nuisance switching. Example: What are the settings for a unit with a discharge temperature setpoint of 70 F and temperature rise of 90 F? Setpoint = 70 F (0.5 x 90 F) + 5 F = 30 F Differential = 3 F Referring back to the Definitions, the following is the sequence of operation for the control: o o Once the outside air temperature falls to 27 F (30 F Setpoint - 3 F Differential), the gas controls will be enabled. Once the gas controls are enabled, they will remain enabled until the temperature rises above the 30 F Setpoint. Figure 5.1 Mild Temperature Thermostat Settings for Model Sizes (Digit 4-6) 500 to 800 JOHNSON AA-1C SHOWN WITH FRONT COVER REMOVED (CONTROL IS LOCATED IN THE BLOWER ELECTRICAL COMPARTMENT) JUMPER POSITION HEATING COM N.O. FURNACE #2 FURNACE #1 FACTORY WIRING

6 30 F INSTALLATION/SETUP Electronic Mild Temperature Thermostat Calculation Method (continued) Settings for Model Sizes (Digit 4-6) = 840 through 960 For these units, the Setpoint and Differential must be set on the controller and S350. The Setpoint is typically set as follows: Setpoint = Discharge Temperature (0.33 x T) + 5 F The Differential on both and S350 are typically set at 3 F to avoid nuisance switching. The Offset on the S350 is typically set as following this 3-step process: a. Calculate Desired Stage Setpoint = Discharge Temperature (0.67 x T) b. Calculated Offset = Setpoint Calculated Desired Stage Setpoint c. Actual Offset is one of the following: a. If Calculated Offset 30 F, then Offset=Calculated Offset 5 F b. If Calculated Offset>30 F, then Offset=30 F 5 F = 25 F Example #1: What are the settings for a unit with a discharge temperature setpoint of 75 F and temperature rise of 100 F? Setpoint = 75 - (0.33 x 100) + 5 F = 47 F Once the outside air temperature falls to 44 F (47 F Setpoint - 3 F Differential), the gas controls of Furnace #2 will be enabled. Differential on and S350 = 3 F Calculate Desired Stage Setpoint = 75 (0.67 x 100) = 8 F Calculated Offset = 42 F 8 F= 34 F Since 34 F > 30 F, Offset = 30 F 5 F = 25 F Once the outside air temperature falls to 19 F (47 F Setpoint 25 F Offset 3 F Differential), the gas controls of Furnace #3 will be enabled. Example #2: What are the settings for a unit with a discharge temperature setpoint of 75 F and temperature rise of 60 F? Setpoint = 75 - (0.33 x 60) + 5 F = 60 F Once the outside air temperature falls to 57 F (60 F Setpoint - 3 F Differential), the gas controls of Furnace #2 will be enabled. Differential on and S350 = 3 F Calculate Desired Stage Setpoint = 75 (0.67 x 60) = 35 F Calculated Offset = 60 F 35 F = 25 F Since 20 F 30 F, Offset = 25 F 5 F = 20 F. Once the outside air temperature falls to 37 F (60 F Setpoint 20 F Offset 3 F Differential), the gas controls of Furnace #3 will be enabled. Figure 6.1 Mild Temperature Thermostat Settings for Model Sizes (Digit 4-6) 840 to 960 JOHNSON AA-1C AND S350AA-1C SHOWN WITH FRONT COVERS REMOVED OFFSET (CONTROL IS LOCATED IN THE BLOWER ELECTRICAL COMPARTMENT) JUMPER POSITION HEATING COM N.O. S350 COM N.O. FURNACE #3 FURNACE #2 FURNACE #1 FACTORY WIRING

7 INSTALLATION/SETUP Electronic Mild Temperature Thermostat Settings Adjustments The mild temperature thermostat control must be setup and adjusted to properly lockout the gas controls as outside temperatures increase and re-enable the controls as outside temperatures fall. This is to minimize furnace cycling when heating demand is below the minimum turndown of the furnace and additional heating is not needed. Figure 7.1 and S350 (With Covers On) 1. Remove the controller cover(s) by loosening the cover screws, accessible from the front of the control. Each controller block has 4 screws. Units with Model Digits 4-6 = 75 to 800 have one (1) Johnson Controls main control block. Units with Model Digits 4-6 = 840 to 960 have one (1) Johnson Controls main control block and one (1) S350 stage adder control block. 2. To set the controller (refer to Figures 7.1 and 7.2): a. Verify that the heating/cooling jumper blocks are in the HEATING position. b. Adjust the differential potentiometer DIFF to the desired number of degrees between relay energized and de-energized. This is typically set for 3 F. c. The Setpoint will be set once the cover is secured back on the controller. 3. To set the S350 stage adder (if equipped): a. Verify that the heating/cooling jumper blocks are in the HEATING position. b. Adjust the differential potentiometer DIFF to the desired number of degrees between relay energized and de-energized. This is typically set for 3 F. c. Adjust the Offset to the value determined in the preceding section (using either the Table Method or the Calculation Method). 4. Replace the cover(s) and fasten in place with the four screws on each cover. 5. Adjust the Setpoint dial on the front of the to the desired setting. Figure 7.2 and S350 (With Covers Off) DIFF S350 OFFSET S350 DIFF

8 INSTALLATION/SETUP Electronic Mild Temperature Thermostat Modine Manufacturing Company has a continuous product improvement program, and therefore reserves the right to change design and specifications without notice. Modine Manufacturing Company 1500 DeKoven Avenue Racine, Wisconsin, USA Phone: (HEAT) Modine Manufacturing Company