Desa H) AND VM42EP(B Owner's Operation And Installation Manual

Also see for H) AND VM42EP(B: OWNER'S OPERATION AND INSTALLATION MANUAL OWNER'S OPERATION AND INSTALLATION MANUAL

Contents

www.desatech.com 108796-01K22TROUBLESHOOTINGNote: Before troubleshooting the system, make sure the gas shutoff valve is ON. The two most commoncauses of a malfunctioning gas appliance are:1. Loose wiring connections2. Construction debris clogging the pilot and/or gas control valve filterOBSERVED PROBLEMIgnitor will not spark or pilot willnot lightPilot will not stay litNo gas to burner, although wallswitch and valve are set to theON positionPOSSIBLE CAUSE1. No gas supply or shutoffvalve is OFF2. Air in gas line3. Construction debris clog-ging pilot orifice4. Low gas pressure5. Kinked pilot line6. Control valve knob is notopening7. No power to unit or theignition module or powertransformer is bad8. Vent damper not fully open1. Loose wiring on ignitor wireto ignition module and/or poorground to ignition module2. Pilot flame too low to sense1. Wall switch wires defective ortoo long2. Thermopile not generatingsufficient voltageREMEDY1. Check to see if you have gassupply and that equipmentshutoff valve is opened2. Repeat lighting procedure sev-eral times to purge all air out oflines. If after repeated attemptsappliance does not light, call forqualified service and repair.3. Remove debris and dirt, in-spect and clean any otherpossible obstructions4. Contact your gas supplier tocheck pressure5. Have a qualified technicianreplace pilot line6. Replace control valve (Refer toReplacement Parts, page 20)7. Check that main power is onand that all wire connectionsare made correctly to theignition model (see WiringDiagram, page 21). Check for24 VAC at the secondary sideof the transformer. If 24 VACis present and the module doesnot operate, have the modulereplaced otherwise have thetransformer replaced8. Open vent damper until fullylocked in OPEN position1. Check wiring connection.Refer to wiring diagram (seeWiring Diagram, page 21)and/or check ground wire toignition module2. Clean and adjust pilot burnerand check gas supply and inletpressure to unitNote: Have a qualified technicianreplace pilot assembly if brokenor corroded1. Check electrical connections2. Recheck problems 1 and 2