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1 / VENTURI MANIFOLD FOR VK41.5V/VK81.5V GAS CONTROLS PRODUCT HANDBOOK APPLICATION The venturi manifold combined with the VK41.5V/VK81.5V gas controls and a specific DC-fan is called CVI-vf (Combined Valve Ignition, venturi and fan) and has been specially developed for modulating fully premix appliances. Note: The information of this handbook supplements those of the Product Handbook EN2R-9004 of The Combined Valve and Ignition systems (CVI) and the product handbook EN2R-9017 of the V5306V integrated 1:1 gas/air regulator The information of this handbook specifies the today supplementary features and data but also limitations on models and specifications of the CVI Gas Control with the / venturi manifold. Subject to change without notice. All rights reserved. General Contents Description... 2 Features... 2 Technical Specifications... 3 Dimensional drawing... 4 Dimensional drawing venturi manifold... 5 Adjustments and Checkout... 6 Various Standards and approvals... 6 Application notes... 6 Ordering information... 7 Accessories EN2R R13-NE

2 DESCRIPTION The venturi manifold is a gas/air mixing unit that allows modulation of a premix burner with constant gas/air ratio down to 20% of maximum load. It is to be used in combination with a fan and a Honeywell 1:1 regulating gas valve. The modulation is accomplished by changing the fan speed. The outlet pressure of the gas valve is regulated to ambient pressure by the gas valve. The venturi generates a negative pressure against ambient by which the gas is drawn through the gas valve outlet. The venturi manifold system is designed to be fitted in up to eight positions on a specially adapted DC fan, using two supplied M5 thread forming screws. The venturi manifold is sealed with a gasket that is supplied with the assembly. The gas valve can be fitted directly on the manifold assembly in horizontal and vertical position with both the side outlet and the end outlet. Four M4 screws and a special NBR gasket are used for the end outlet version. Three M5 screws and a special sealing ring are used for the side outlet version. The venturi manifold can be trimmed to the correct gas/air ratio by turning the throttle screw FEATURES The following features are deviating from Product handbook VK41../VK81.. series (EN2R-9004) General In combination with CVI, all burner control and safety functions are concentrated in one optimised system (function integration) All adjustments and test points from one (top) side accessible. Wide modulation band ( % boiler load) or lower fan speed at normal modulation band ( % boiler load) are possible. Flexible mounting positions of gas control to venturi housing and venturi housing to fan. Built in throttle function (venturi manifold) for adjustment on gas type. Options LP gas models with integrated injection orifice. EN2R R13-NE 2

3 SPECIFICATIONS Model Code 1) Inlet and outlet code 2) Reference load 3) x kw x kw x kw x50 *) kw x kw x kw x kw x kw 1 )x = 0: with gasket and screws x = 2: without gasket and screws 2 ) The inlet and outlet codes are visible on the top and bottom plastic parts. 3 ) The reference load is the gross boiler load at which the venturi has an overall pressure drop of 450 Pa Dimensions See Dimensional drawing on page 4 Ambient temperature C Gas valve connection A flange connection set is required to mount the manifold assembly onto the gas valve. (See Accessories on page 8) Minimum load The minimum load for which the unit can be used is 20% of the reference load, which equals a minimum pressure differential of 50 Pa of the 1:1 gas control. Throttle range With the throttle an air factor of 1.3 is adjustable in the H, L and LL-band of natural gas. Material Housing: ZnAl4Cu1 (Z410, Zamac Z5) Venturi: statically dissipative POM Throttle screw: brass Fan plate gasket: cork nitrile rubber Seals: rubber (NBR) Pressure drop 450 Pa maximum at reference load. (Overall pressure drop of the venturi) Venturi pressure 1250 Pa minimum at reference load. (The venturi pressure is the determination of the effective gas pressure) Tracking inaccuracy (not applicable for inlet and outlet code 050 * ) The tracking inaccuracy is the deviation from a constant gas/ air ratio over the modulation band % Typical: 10% without internal injection orifice. 5% with internal injection orifice. Code x55: 15% without internal injection orifice. 7.5% with internal injection orifice. *) Only suitable in specially adapted applications 3 EN2R R13-NE

4 DIMENSIONAL DRAWING 60 G.126/RG130 Air inlet Gas inlet CVI R1 EN2R R13-NE 4

5 DIMENSIONAL DRAWING VENTURI MANIFOLD R38 Screw M5 thread forming at R '(2x) R48 Ø (2) EN2R R13-NE

6 ADJUSTMENTS AND CHECKOUT Adjustment Check gas input to the appliance using a pressure gauge (resolution of 1 Pa (0.01 mbar) or better) connected to the outlet pressure tap. Put CO 2 meter probe (inaccuracy < 0.1%) into exhaust gas outlet. Screw throttle adjustment screw approx. half way down (about 10 mm turned down). ❶ Start appliance ❷ Run appliance at maximum load. ❸ Observe CO 2 meter and adjust throttle screw until CO 2 percentage is at nominal value.turn throttle screw clockwise to reduce gas flow and CO 2 percentage ❹ If appliance does not start, turn throttle screw three turns counter clockwise and repeat starting procedure. ❺ Keep appliance running until completely stabilised, accurate adjustment when necessary. ❻ Set appliance to minimum load. ❼ Check offset pressure according to the manufacturer s instructions. Repeat from 1 to 6 inclusive when adjustment of offset pressure was necessary. After adjustments are made, stop appliance, disconnect pressure gauge and CO 2 meter and tighten outlet pressure tap. Final checkout of the installation After any adjustment, set appliance in operation. Observe several complete cycles to ensure that all burner components function correctly. STANDARDS AND APPROVALS The venturi manifold is not certified separately. It will be certified as part of the appliance. APPLICATION NOTES Make sure the venturi inlet is not obstructed. This will influence the air factor. If the distance from another boiler component to the venturi inlet is more than 50 mm, air factor and boiler load are not influenced. There is a strong interaction between the venturi, gas control and burner. For this reason it is important to fit the characteristics of these components to each other. If not matched well, for instance acoustic problems could be generated. It is recommended to test the appliance at both cold start and hot start conditions with high and low caloric test gases. EN2R R13-NE 6

7 ORDERING INFORMATION When ordering specify: Order number of venturi manifold required: see table below. Ordering Specification Reference load number kw kw kw ) 56 kw ) 40 kw ) 27 kw )* 82 kw ) 72 kw ) 46 kw ) 34 kw 1) without gasket and screws. * only suitable in specially adapted applications. Model number of VK41.5V/VK81.5V gas control. The fan should be obtained from the fan manufacturer: G.126 of EBM or RG130 from MVL. Order numbers of replacement parts and accessories required: See Accessories on page 8. Note: Most models of valves, replacement parts and accessories will be available under TRADELINE label. Ask your wholesaler for details. 7 EN2R R13-NE

8 ACCESSORIES Accessories for VK41.5/VK81.5V series gas controls Description Packing quantity Ordernumber Sealing ring and screws for mounting onto side outlet Gasket and screws for mounting onto end outlet Sealing ring for mounting onto side outlet Gasket for mounting onto fan Gasket for mounting onto fan Screws for mounting fan onto venturi Orifice for LPG application Code venturi Orifice dia (mm) Packing quantity Order number x x x x x x x Manufactered for and on behalf of the Environmental and Combustion Controls Division of Honeywell Sàrl, Ecublens, Route du Bois 37, Switzerland by its Autorized Representative: Automation and Control Solutions Combustion Controls Europe Honeywell BV Phileas Foggstraat AJ Emmen The Netherlands Tel.: +31 (-) Fax: +31 (-) EN2R R13-NE 8