Honeywell Thermostat V4944 User Manual - Honeywell Thermostat Manual Download

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Honeywell Thermostat V4944 User Manual

V4943/V8943B,C,N; V4944/V8944B,C,L,N Regulating Diaphragm Gas Valves PRODUCT DATA FEATURES • Models are available for natural or liquid petroleum (LP) gases. • Valve models L, N are rapid opening (less than six seconds) and fast closing, and are available for LP and natural gases, respectively. • Line voltage with two-wire thermostat or controller is used with V4943; V8943 is used with 24V thermostat or controller. • V4944 is used with line voltage dual-stage thermostat or controller; V8944 is used with 24V dual-stage thermostat or controller. • Slow opening B,C valve models are available for natural and LP gases respectively. • Valve closes on power failure; recommended for final shutoff service. APPLICATION • Valve closing time: 2 seconds maximum at 7 inches wc inlet pressure. The V4943/V8943B and N (single stage) and V4944/V8944B and N (two stage) are solenoid-operated diaphragm valves • Valves rated for 0.5 pound per square inch (psi) (3.4 suitable for natural gas only. The V4943/V8943C and kPa). V4944/V8944C and L are solenoid-operated diaphragm • Leadwires and cover for electrical conduit connections valves suitable for Liquefied Petroleum (LP) gas only. These are provided. valves are used on boilers, unit heaters, duct furnaces, makeup air and rooftop heaters. Contents Application ........................................................................ 1 Features ........................................................................... 1 Specifications ................................................................... 2 Ordering Information ........................................................ 2 Installation ........................................................................ 6 Operation .......................................................................... 9 Checkout and Troubleshooting ......................................... 10 Service Information .......................................................... 12 65-0214-08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES SPECIFICATIONS Models: All models are solenoid-operated regulating diaphragm gas valves. Details are shown in Table 1. Table 1. Model Availability. Power Maximum Voltage Consumption Operating Opening Number and Maximum (VA Pipe Size Thread Pressure Time Pressure Type of of Lead- Model Frequency Current Maximum) (in.) Type psi kPa (sec.) Regulation Gas wires V4943B 120V 0.055A 6.6 1, 1-1/4, NPT 0.5 3.4 3 to 25 Single Naturala 2 (+10%, 1-1/2, 2 stage V4943N-15%), 1, 1-1/4, <6 60 Hz 1-1/2 V8943B 24V,(+10%, 0.363A 9.0 1, 1-1/4, 3 to 25 -15%) 1-1/2, 2 V8943C50/60 Hz 1, 1-1/4 LP V8943N 1, 1-1/4, <6 Naturala V4944B 120V 0.077A 9.01-1/2 3 to 25 Two stage 3 V4944C (+10%, LP -15%) V4944L60 Hz 1-1/4 <6 V4944N 1, 1-1/4, Naturala V8944B 24V 0.470A 11.31-1/2, 2 3 to 25 V8944C(+10%, 1, 1-1/4, LP -15%) 1-1/2 50/60 hz V8944L 1, 1-1/4 <6 V8944N 1, 1-1/4, Naturala 1-1/2, 2 a Includes natural gas, mixed air-natural gas, LP gas-air. Flow Capacity: See Table 2. Valve Pattern:Straight-through, non offset. Table 2. V4/8943 and V4/8944 Flow Capacity. Valve Body Material:Die-cast aluminum. CSA Regulation Capacities Electrical Terminations:1/4 in. (6 mm) spade terminals Certified Btuh per 0.64 sp gr Natural Gas (quick connects). Leadwires and cover for electrical conduit 1.0 in. pd 1000 cfh connections are provided. Pipe Size Natural Natural Maximum Minimum (in.) Gas cfh gas cfh cfh Valve Closing Time: On power failure, a maximum of 1 1,000 1,000,000 1,000 300 2 seconds at 7 in. wc inlet pressure. 1-1/4 1,600 1,600,000 1,600 480 Ambient Temperature Ratings: -40°F to +150°F (-40°C to 1-1/2 2,300 2,300,000 2,300 780 +66°C). 2 3,000 3,000,000 3,000 870 Maximum Fluid Temperatures: 150°F (66°C). ORDERING INFORMATION When purchasing replacement and modernization products from your TRADELINE® wholesaler or distributor, refer to the TRADELINE® Catalog or price sheets for complete ordering number. If you have additional questions, need further information, or would like to comment on our products or services, please write or phone: 1. Your local Honeywell Environmental and Combustion Controls Sales Office (check white pages of your phone directory). 2. Honeywell Customer Care 1885 Douglas Drive North Minneapolis, Minnesota 55422-4386 3. http://customer.honeywell.com or http://customer.honeywell.ca International Sales and Service Offices in all principal cities of the world. Manufacturing in Belgium, Canada, China, Czech Republic, Germany, Hungary, Italy, Mexico, Netherlands, United Kingdom, and United States. 65-0214—08 2 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES Pressure Reference Port Vent: 5/16–24 UNF internal Weight: tapping. 1 in., 1-1/4 in. valves: 4 lb (1.8 kg). 1-1/2 in., 2 in. valves: 5 lb (2.3 kg). Standard Factory Settings: See Table 3. Dimensions: See Fig. 1. Table 3. Factory Settings and Regulation Ranges. Natural Gas (i.e. B, N models) LP Gas (i.e. C, L models) Firing stagesa Factory Setting Adj. Rangeb Factory Setting Adj. Rangeb Low Fire: Standard Models 0.8” wc 0.8” to 2” wc 1.4” wc 1.4” to 4.2” wc Special Models (Group 1) 1.6” wc 1.6” to 4.2” wc Special Models (Group 2) 0.8” wc 0.8” to 2” wc Special Models (Group 3) 0.8” wc 0.8” to 2” wc High Fire: Standard Models 3.5” wc 3” to 4.5” wc 10” wc 8.8” to 11.5” wc Special Models (Group 1) 3.5” wc 3” to 4.5” wc Special Models (Group 2) 3.5” wc 1.4” to 4.2” wc Special Models (Group 3) 5” wc 4.0” to 7” wc a V4943 is a single-stage valve, please refer to “High Fire” for spring specifications. b Do not adjust or operate valve outside of the specified ranges. CAUTION DO NOT adjust or operate valve outside of the specified ranges. Valve will not regulate or work properly. Special Models (Group 1): V4944B1075, V4944B1083, V4944B1091, V8944B1092, V8944B1100, V8944B1118 Special Models (Group 2): V4944B1109, V4944B1125, V4944B1141, V4944B1166; V4943B1050, V4943B1068, V4943B1076, V4943B1084 Special Models (Group 3): V4944B1117, V4944B1133, V4944B1158; V4943B1092, V4943B1100, V4943B1118 Approvals: Underwriters Laboratories Listed: File Number MH1639 CSA Certified: Report Number C2030020 (except those listed as Special Models Group 2 and Special Models Group 3) Commonwealth of Massachusetts Product Certification Number: G1-12-05-22 Mounting Position: Accessories: Standard Position: Upright (horizontal). AT72D Transformer (40 VA) for all 24 Vac models. 204480 Vent Pipe Adapter NOTE: V4944B1059, V4944N1052 and V4944N1060 can be mounted upright to 90 degrees from the upright on the horizontal axis with respect to the inlet connection. 3 65-0214—08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES SIDE VIEW TOP VIEW 6 (152) 6-9/16 (167) FOR 1, 1-1/4 6 PRESSURE OR (152) REGULATOR 7-3/8 (187) ADJUSTMENT FOR 1-1/2, 2 CAPS ATMOSPHERIC PRESSURE REFERENCE PORT WITH INTERNAL VENT LIMITER INLET OUTLET PRESSURE PRESSURE TAP TAP M23375 Fig. 1. V4943/44 and V8943/44 dimensions in in. (mm). Gas Valve Sizing 7. At the point of intersection of the vertical line and the curve, draw a horizontal line to intersect the flow 1. Check the burner nameplate for: (capacity) scale. The point of intersection indicates the a. the type of gas used, and capacity that can be obtained with the maximum b. the gas flow capacity. The capacity will be listed in pressure drop. British thermal units per hour (Btuh) or in cubic feet 8. If the capacity at the maximum pressure drop is per hour (cfh). insufficient, use the capacity vs. pressure drop curve for 2. Contact the local gas utility for information regarding: the next larger valve size and repeat steps 6 and 7. a. the specific gravity (sp gr) and b. the Btu per cubic foot (Btucf) for the type of gas used. 1 INCH V4/8944B/N REGULATION AREA 3. Find the capacity in cf/h. If the capacity is listed in Btu, 100 convert to cf/h using the following formula: Capacity in cfh = Btuh (burner nameplate) Btu/cf (gas utility) 4. For gases with specific gravities other than 0.64, multiply 10 PO > 2 IN. the burner cf/h using the proper conversion factor in Table 4. ANY PO Table 4. Gas Conversion Factors. Type of Gas sp gr (average) Multiply cfh by 1 PO < 2.5 IN. Manufactured 0.60 0.968 PRESSURE DROP (IN. WC) Mixed 0.70 1.046 LP-Propane 1.53 1.546 LP-Butane 1.98 1.759 0.1 5. Use the corrected burner capacity in cfh when determin- 100 1000 10000 FLOW NATURAL GAS (CFH) ing the gas valve size in Figs. 2–9. M23376 6. Determine the maximum pressure drop across the valve and draw a vertical line at this pressure in Figs. 2–9. Fig. 2. Capacity vs. pressure drop of Natural Gas curves for 1 in. valve. 65-0214—08 4 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES 1.25 INCH V4/8944B/N REGULATION AREA 2 INCH V4/8944B/N REGULATION AREA 100 100 10 10 PO > 2 IN. PO > 2 IN. ANY PO ANY PO 1 PO < 2.5 IN. 1 PRESSURE DROP (IN. WC) PRESSURE DROP (IN. WC) 0.1 0.1 100 1000 10000 100 1000 10000 FLOW NATURAL GAS (CFH) M23377 FLOW NATURAL GAS (CFH) M23379 Fig. 3. Capacity vs. pressure drop of Natural Gas Fig. 5. Capacity vs. pressure drop of Natural Gas curves for 1-1/4 in. valve. curves for 2 in. valve. 1.5 INCH V4/8944B/N REGULATION AREA 100 1 INCH V4/8944C/L REGULATION AREA 100 10 PO > 2 IN. 10 ANY PO ANY PO PO < 2.5 IN. 1 PRESSURE DROP (IN. WC) 1 PO < 7 IN. PRESSURE DROP (IN. WC) 0.1 100 1000 10000 0.1 FLOW NATURAL GAS (CFH) M23378 100 1000 10000 FLOW LP GAS (CFH) M23380 Fig. 4. Capacity vs. pressure drop of Natural Gas curves for 1-1/2 in. valve. Fig. 6. Capacity vs. pressure drop of LP Gas curves for 1 in. valve. 5 65-0214—08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES 1.25 INCH V4/8944C/L REGULATION AREA 2 INCH V4/8944C/L REGULATION AREA 100 100 10 10 ANY PO ANY PO PO < 5.5 IN. 1 1 PO < 8 IN. PRESSURE DROP (IN. WC) PRESSURE DROP (IN. WC) 0.1 0.1 100 1000 10000 100 1000 10000 FLOW LP GAS (CFH) M23381 FLOW LP GAS (CFH) M23383 Fig. 7. Capacity vs. pressure drop of LP Gas Fig. 9. Capacity vs. pressure drop of LP Gas curves for 1-1/4 in. valve. curves for 2 in. valve. To size two identical valves piped in series: 1.5 INCH V4/8944C/L REGULATION AREA 1. Find the cf/h for the type of gas used. 100 2. Consider both valves as one unit. Determine the maximum pressure drop across the one unit. 3. Find the pressure drop across the first valve by assuming it to be 45 percent of the total pressure drop. 4. Find the valve size from Figs. 2–9. 5. The second valve will be the same size as the first valve. 10 ANY PO INSTALLATION PO < 8 IN. 1 WARNING PRESSURE DROP (IN. WC) Explosion hazard. Can cause serious injury, death or equipment damage. Installation and service by trained professionals only. Exceeding the pressure rating or use of unspecified 0.1 fuel can lead to improper operation of the valve and can 100 1000 10000 create an explosion hazard. Property damage, severe FLOW LP GAS (CFH) M23382 bodily injury or death can result. Fig. 8. Capacity vs. pressure drop of LP Gas When installed in the Commonwealth of curves for 1-1/2 in. valve. Massachusetts, the installation and servicing of this product must be done by a licensed gas fitter or plumber. Consult specifications before installing valve. 65-0214—08 6 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES When Installing this Product... 4. Install the valve in a horizontal pipe line in an upright position with the gas flow in the direction indicated by the 1. Read these instructions carefully. Failure to follow them arrow on the casing. The valve must be upright could damage the product or cause a hazardous (electrical connection tower in the up position) on a condition. horizontal axis with respect to the inlet connection 2. Check the ratings given in the instructions and on the (see Fig. 10). Certain models may be mounted in the product to make sure the product is suitable for your limited horizontal position (any position from upright to application. 90 degrees to upright on an horizontal axis with respect 3. Installer must be a trained experienced flame safeguard to the inlet connection. See Specifications section.) control technician. 5. Apply a parallel jaw wrench only to the flat next to the 4. After installation is completed, check out product opera- pipe being inserted. A wrench applied to the valve body tion as provided in these instructions. itself or to the end farthest from the pipe being inserted can distort the casting and cause a malfunction. 6. The gas flow must be in the same direction as the arrow WARNING on the bottom of the valve body. Explosion hazard and electrical shock hazard. Can cause serious injury or death. 1. Turn off gas supply before starting installation. WARNING 2. Disconnect power supply before beginning Explosion and Fire Hazard. installation to prevent electrical shock and equipment Can cause serious injury or death. damage. If flow is not in direction of arrow, valve may not 3. Do not remove seal over valve inlet or outlet until shut off; which can cause excess gas and harm to ready to connect piping. equipment or personnel. 7. Make electrical connections as illustrated in the wiring Prepare Piping and Install Valve (Fig. diagrams (see Figs. 11–14). 10). 8. Turn on the main gas and, with a soap solution, check the valve installation for leaks. 1. Use new, properly reamed pipe free from chips. 9. The V4943/V8943, V4944/V8944 combination valve 2. Do not thread pipe too far. Valve distortion or malfunction pressure regulating sections are provided with integral can result from excess pipe in valve. vent limiters. 3. Apply good quality pipe dope resistant to the action of LP gas; put a moderate amount only on the pipe threads. If pipe dope lodges on the valve seat, it will prevent proper closure. 7 65-0214—08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES EXCESS DOPE CAN PUSH DISK TWO CLEAN OFF THE THREADS, VALVE MODERATE SEAT AVOID AMOUNT USING OF DOPE VALVE AS LOOSE HANDLE CORRECT CHIPS INCORRECT NORMAL TOO LONG; FULL THREAD DISTORTS VALVE SEAT CORRECT REAM PIPE, INCORRECT NORMAL BLOW OUT CHIPS (THAT TOO LONG, FULL CAN LODGE ON SEAT) DISTORTS THREAD VALVE SEAT INCORRECT WRENCH CORRECT CORRECT HERE STRAINS VISE GRIPS WRENCH VALVE BODY END NEXT CORRECTLY TO PIPE APPLIED NEXT BEING TO PIPE BEING INSERTED INSERTED M6877 Fig. 10. Preparing the piping and installing the valve. Wiring 4. Check the power supply circuit. The voltage and frequency must match those of the valve. 5. See Fig. 11 through 14 for typical field wiring connections. Follow the burner manufacturer wiring WARNING diagram, if provided. Electrical Shock Hazard. 6. Make wiring connections at the electrical wires provided Can cause serious injury, death or equipment at the top of the valve. damage. Disconnect the power supply before making connections to prevent electrical shock and equipment CAUTION damage. Equipment Damage Hazard. Miswiring can cause equipment damage. 1. All wiring must comply with applicable electrical codes, 1. Label all wires prior to disconnection when servicing ordinances and regulations. Use NEC Class 1 (line valves. Wiring errors can cause damage to the voltage) wiring. equipment through improper and dangerous 2. For normal installations, use moisture-resistant No. 14 operation. wire suitable for at least 167°F (75°C) when using a 2. Verify proper operation after servicing. flame safeguard primary control, or for at least 194°F 3. After the installation is complete, cycle the valve (90°C) when using a flame safeguard programming several times with the manual fuel shutoff cock control. closed. Make sure the valve and actuator function 3. For high temperature installations, use properly. moisture-resistant No. 14 wire selected for a temperature 4. If the installation is gas tight and functioning properly, rating above the maximum operating temperature. proceed to the Checkout section. 65-0214—08 8 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES V4943B,C,N TWO-STAGE CONTROLLER LINE VOLTAGE SINGLE-STAGE VALVE THERMOSTAT PV PV FLAME OR CONTROLLER MV SAFEGUARD LIMIT(S) CONTROL BLACK BLACK ORANGE BLUE L2 JUNCTION L1 1 BOX HOT 1 PV MV L1 ORANGE L2 (HOT) PV MV FLAME TRANSFORMER LIMIT(S) SAFEGUARD V8944B,C, L, N CONTROL TWO-STAGE VALVE 1 POWER SUPPLY. PROVIDE DISCONNECT MEANS 1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED. M6887 AND OVERLOAD PROTECTION AS REQUIRED. 2 V8944B1050, V8944B1068, V8944B1076,V8944B1084 V8944C1041, V8944C1058, AND V8944C1066 HAVE A Fig. 11. Typical wiring diagram for V4943B,N. MOLEX® CONNECTOR WITH 72 IN. (1829 MM) LEAD WIRES: ORANGE (MV), PINK (PV), GRAY (COM). M6889A V8943B,C,N 24-VOLT SINGLE-STAGE THERMOSTAT Fig. 14. Typical wiring diagram for V8944B,C,L,N with three VALVE LIMIT(S) PV PV leadwire electrical termination. MV OPERATION BLACK ORANGE L1 (HOT) 1 L2 General TRANSFORMER FLAME SAFEGUARD The V4943/V8943B,C, N and V4944/V8944B,C,L, N Valves are CONTROL solenoid-operated diaphragm gas valves with one or two 1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED. stages of regulation. They can operate as a shut-off valve and M6888B a pressure regulating valve. The V4943/V8943B,C,N have a single stage of regulation (high fire) and the V4944/ Fig. 12. Typical wiring diagram for V8943B,C,N. V8944B,C,L,N have two stages of regulation (high fire and low fire). The models with L and N suffixes are rapid opening devices while the B- and C-suffixed models are slow opening FLAME SECOND SAFEGUARD STAGE devices. LIMIT(S) CONTROLLER CONTROL CONTROLLER In a redundant valve (two valves in series) system, it is recommended that the V4943/V8943B,C, N and V4944/V8944B,C,L, N Valves be positioned downstream from L1 (HOT) the redundant valve for proper operation of the pressure 1 regulator(s). The V4943/V8943N and V4944/V8944L,N models L2 have a 0.022 in. bleed orifice in the bleed line (the valves bleed internally to the outlet side) and are rapid opening valves (maximum opening time is six seconds). The V4943/V8943B,C and V4944/V8944B,C models have bleed orifices varying in diameter from 0.014 to 0.018 in. to control the opening time. BLACK BLUE ORANGE V4944B,C,L,N The range of outlet pressure is adjusted by turning a screw PV PV MV TWO-STAGE VALVE which changes the compression in the regulator spring. The MV valves are suitable for natural gas (B and N models) or LP COM (C and L models) applications. Do not adjust or operate valve STG 1 STG 2 outside of the specified ranges (see Table 3). 1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED. M6886B Leadwires and a cover for electrical conduit connections are provided with each valve. Fig. 13. Typical wiring diagram for V4944B,C,L,N with three leadwire electrical termination. The valves are available in 1 in., 1-1/4 in., 1-1/2 in. and 2 in. sizes. The 1 in. and 1-1/4 in. valves share a common body casting and the 1-1/2 in. and 2 in. valves share a larger body casting. The valves are intended to replace the V4843/V8843B,C,N and V4844/V8844B,C,N lines of valves. The valves are used as combination controls, providing both pressure regulation and shutoff functions for burners. Typical burner applications include boilers, process equipment, ovens, incinerators, water heaters, rooftop units, and commercial/ industrial atmospheric/power burners. The burner firing rates range from 400 kbtu/hour to 5,000 kbtu/hour. 9 65-0214—08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES Operation of the V4943B,C,N/ Operation of the V4944/V8944B,C,L,N V8943B,N Valves The V4943/V8943B,C,N Valves are combination gas controls These models use two pressure regulators (low fire and high that include a single stage of pressure regulation in addition to fire) and two solenoids to provide two distinct stages of the shut-off function. They have a single solenoid and a single pressure regulation. The first stage pressure regulator solenoid regulating diaphragm. activates the same quick-close orifice valve and servo valve as in the V4943/V8943 models, but the bleed gas now flows When the controller is not calling for heat, the valve solenoid through a first stage (low fire) regulator valve to the outlet. This coil is not energized. Static gas inlet pressure and a spring act maintains the outlet at a pressure controlled by the low fire together to close the valve. In this condition, a three-way servo regulator. The second stage regulator (high fire) is set to a valve directs inlet pressure directly above the main diaphragm, higher outlet pressure. When the second stage solenoid is creating static pressure on both sides of the main diaphragm. energized, gas is shunted past the low fire regulator through a timing orifice. The increased flow of supply gas (due to the On a call for heat, the controller contacts close and the valve second servo valve opening) further reduces the pressure solenoid coil is energized, opening the servo valve and above the main diaphragm, causing it to open more. The allowing the gas that is above the main diaphragm to bleed corresponding increase in outlet pressure forces the low fire downstream, and diverting inlet (supply) gas through a supply regulator closed, and the valve regulates off the high fire orifice. This reduces the pressure above the diaphragm, and regulator. the gas that is bled off flows through a regulating valve to the outlet of the gas valve. The pressure differential across the The V4944/V8944L and N models use a timing orifice that main diaphragm is greater than the spring force, so the valve gives an opening time to low fire of less than six seconds. The opens. The valve opening rate is controlled by a timing orifice slower opening V4944/V8944B and C use timing orifices that through which the bleed gas passes. give an opening time of three to 25 seconds. Once the valve is open, outlet pressure is sensed through the Both regulators can be adjusted separately and the springs are bleed passage. The outlet pressure acts on the regulating sized so that the highest achievable pressure of the low (servo) diaphragm and tends to open or close the integral pressure regulator range is less than the lowest achievable regulating valve until a force balance is established between pressure of the high fire pressure regulator. The high fire the outlet pressure acting on the servo diaphragm and the setpoint cannot be achieved without the first stage solenoid regulator spring that acts on the atmospheric side of the servo being energized. diaphragm. Valve closing operation is identical to that described for V4943/ The system is balanced when the flow of supply gas through V8943B,C,N valves. the supply orifice is equal to the outflow of gas through the regulating valve. The regulated output pressure required to achieve equilibrium is varied by increasing or decreasing the CHECKOUT AND spring force acting on the atmospheric side of the regulating diaphragm. Pressure adjustment is done through the use of a TROUBLESHOOTING threaded nylon screw acting on the regulating spring. Regulator springs with different spring rates provide the various ranges of pressure regulation needed for natural and LP gases. WARNING Explosion or Fire Hazard. After the controller is satisfied, the procedure is reversed. The Can cause serious injury or death. controller contacts open and the solenoid coil is de-energized. Do not let fuel accumulate in the combustion chamber. The plunger is released, moving to the down position. The If fuel is allowed to enter the chamber for longer than a servo valve closes, diverting supply gas away from the orifice few seconds without igniting, an explosive mixture and allowing the gas inlet pressure to act directly above the could result. main diaphragm. The resulting increase in upper chamber pressure, along with the main spring, forces the main diaphragm against the valve seat, stopping the gas flow. CAUTION Equipment Damage Hazard. In the event of a power failure during automatic operation of the Failure to complete tests can cause equipment valve, the V4943/V8943B,C,L,N Valve servo valve closes, damage. diverting supply gas away from the orifice and allowing the gas 1. Do not put the system into service until you have inlet pressure to act directly on the main diaphragm. The satisfactorily completed all applicable tests change in upper chamber pressure, along with the main described in the Checkout section of the instructions spring, forces the main diaphragm against the valve seat, for the flame safeguard control, and any other tests stopping the gas flow. Normal operation will resume upon the required by the burner manufacturer. restoration of power. 2. Close all manual fuel shutoff valves as soon as trouble occurs. 65-0214—08 10 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES Checkout 8. Immerse a 1/4 in. tube vertically 1/2 in. (13 mm) into a jar of water. 1. Valve outlet pressure measurements are made at a point 9. Slowly open the test petcock (F). approximately five pipe diameters downstream from the 10. When the rate of bubbles coming through the water valve outlet. Consider pressure measurements made at stabilizes, count the number of bubbles appearing during the outlet pressure tap as reference measurements only, a ten-second period. Each bubble appearing during a because turbulence and dynamic gas flow effects may ten-second period represents a flow rate of result in erratic pressure readings. approximately 0.001 cfh. 2. Shut off gas supply to valve and make sure valve is closed when setting up pressure measuring equipment. To meet code requirements, leakage must not exceed the 3. Set up pressure measuring equipment. values in Table 5. 4. Make sure the valve is closed. Turn on the supply gas to the valve. Table 5. Allowable Leakage Rates. 5. Set the thermostat or controller to energize the valve and a check the final outlet pressure. See step 1. Allow enough Pipe Size Allowable Number of Bubbles time for the system pressure to stabilize. (in.) Leakage per 10 sec. 6. For regulator setpoint and spring range, please refer to 1, 1-1/4 353 11 (Nat. gas), 7 (LP) Table 3. 1-1/2, 2 453 14 (Nat. gas), 9 (LP) 7. The low pressure regulator (V4944/V8944B,C,L,N) and high pressure regulator V4943V8943B,C,N and a Based on air standard conditions, test pressures in V4944/V8944B,C,L,N) adjustment screws (use a T-40 accordance with ANSI Z21.21, Section 2.4.2 and a maximum six-lobe [TORX®] driver or 5/16-in. standard driver) are of 235 cc/h per inch of seal-off-diameter. Seal-off diameter is located under the slotted aluminum screw cap(s) of the not the same as pipe size. adjustment screw housings (see Fig. 1). To adjust the pressure setting: 11. Close the upstream manual gas cock (A). a. Temporarily remove the slotted aluminum screw cap 12. Close the test petcock (F), remove the test apparatus, and gasket from the housing that contains the and replace the leak test tap plug (D). regulator adjustment setscrew. 13. Open the upstream manual gas cock (A) and energize b. Turn the adjustment setscrew (use a T-40 six-lobe the safety shutoff valve (C). [TORX®] driver or 5/16-in. standard driver) clockwise 14. Test with soap bubbles to make sure there is no leak at to increase the pressure setting or counterclockwise the test tap (D). to decrease the pressure setting. Allow adequate time 15. De-energize the safety shutoff valve (C). (30 to 60 seconds) for the pressure to reach 16. Open the downstream manual gas cock (E). equilibrium between pressure adjustments. 17. Restore the system to normal operation. c. After the regulators have been properly adjusted, replace the gasket and slotted aluminum screw cap ABC D EDOWNSTREAM on the adjustment screw housing. LEAK MANUAL 4 8. Start the system and observe its operation through at TEST GAS COCK TAP least one complete cycle to make sure the valve GAS functions properly. SUPPLY BURNER PRV SSOV UPSTREAM 2 3 MANUAL F Valve Leak Test (See Fig. 15). GAS COCK 1/4 IN. (6 MM) FLEXIBLE MANUAL This test checks the tightness closure of a gas safety shutoff TUBING TEST 1 valve. It should be performed by a qualified technician during 1/4 IN. (6 MM) PETCOCK ALUMINUM OR the initial startup of a burner system, or whenever the valve is COPPER PILOT replaced (see Service Information section). It is recommended TUBING JAR OR GLASS that this test also be included in scheduled inspection and WITH WATER maintenance procedures. 1. De-energize the control system to make sure there is no 1 (13 MM) power to the safety shutoff valve (C) shown in Fig. 15. 2 2. Close the upstream manual gas cock (A). CUT AT 3. Make sure the manual test petcock (F) is closed in the 45 DEGREE ANGLE leak test tap assembly (D). 1 CAN ALSO BE A PERMANENT PETCOCK. 4. Remove the leak test tap plug (valve outlet pressure tap can be used as a test tap) and connect the test 2 PRV = PRESSURE REGULATING VALVE. apparatus to the leak test tap (D). 3 SSOV = SAFETY SHUTOFF VALVE. 5. Close the downstream manual gas cock (E). 4 USE ONLY ONE OF THE DOWNSTREAM TAPS ON THE SS0V. 6. Open the upstream manual gas cock (A). M9547F 7. Run the safety shutoff valve (C) to its fully open position (through the safety system); then immediately Fig. 15. Valve leak test. de-energize the system to close the valve. 11 65-0214—08 V4943/V8943B,C,N; V4944/V8944B,C,L,N REGULATING DIAPHRAGM GAS VALVES Troubleshooting a. Make sure that the gas flow is in the direction of the arrow on the valve body. b. Make sure the valve actuator is wired in the correct circuit. Open the master switch to remove power WARNING from the valve actuator. If the valve closes now, the Electrical Shock Hazard. actuator may not be wired properly. Check and Can cause electrical shock or equipment damage. correct the wiring, if necessary. Use utmost care during troubleshooting. Line voltage c. Look for a short in the electrical circuit. is present right at the electrical terminations for the V4943B,C,N and V4944B,C,L,N valves, and present in all controller circuits for all V4943/V8943 and V4944/ SERVICE INFORMATION V8944 valves. IMPORTANT Do not assume that the valve must be replaced until WARNING all other sources of trouble have been eliminated. Electrical Shock Hazard Can cause serious injury, death or equipment 1. If the valve will not open when the thermostat or damage. controller calls for heat: 1. Only qualified service technicians should attempt to a. Check that there is voltage at the proper electrical service or repair flame safeguard controls and terminations. Be careful—there should be line burner systems. voltage at the actuator of V4943 and V4944 valves. 2. Line voltage is present in the electrical circuits to the b. If there is no voltage at the actuator, first make sure valve. Open the master switch before replacing the line voltage power is connected to the master valve. switch, the master switch is closed and overload protection (circuit breaker, fuse or similar device) has not opened the power line. Scheduled Inspection and c. For V8943A only: If line voltage power is correct, Maintenance check transformer output. Replace the transformer if necessary. For periodic inspection and maintenance, set up a schedule d. If there is still no voltage at the actuator, make sure and follow it. Include the burner valves (check for external all appropriate contacts in the thermostat or leakage around all seals and joints with leak detector; also controller, limits and flame safeguard control are check for internal valve seat leakage—see Valve Leak Test closed. If one or more is open, determine the section) and all other controls. Refer to the flame safeguard cause(s) and correct the condition(s) before control instructions for more information. proceeding. e. If there is proper voltage at the valve actuator but the valve still does not open, first check that the gas CAUTION pressure at the valve is normal. Equipment Damage Hazard. f. If the valve still does not open, replace the valve. Can cause equipment damage or improper 2. If the valve will not close when one or more of the operation. appropriate contacts in the thermostat or controller, Label all wires prior to disconnecting when servicing limit(s) or flame safeguard control is open: valves. Wiring errors can cause improper and dangerous operation. Verify proper operation after servicing. Automation and Control Solutions Honeywell International Inc. 1985 Douglas Drive North ® U.S. Registered Trademark Golden Valley, MN 55422 © 2011 Honeywell International Inc. 65-0214—08 M.S. Rev. 09-11 customer.honeywell.com Printed in United States

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