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Heating, Air Conditioning, Fridge, HVAC/Rheem Criterion RGVG furnace problem


QUESTION: Woke up this morning to VERY cold house.  Honeywell Programmable thermostat set at 68 degrees. I cycled the thermostat and the induced draft motor went through pre-purge. I heard the pressure switch close(I think that is what I hear when it finishes the pre-purge)and ignition start.  After 30 secs the circulating fan came on but no warm air is produced.  I re-tried this a couple of times to verify I'm not crazy.  Started thinking maybe I was out of propane but not the case. I replaced the ICB in August 2010 plus the flame sensor. I have 24 volts at R wire and am heading up to the unit now.  I'll check the board, flame sensor and pressure switch too I guess. Any ideas what is going on?


If ignition starts ( do you have a glow coil or spark ignition,) if spark ignition and you have a pilot tube connecting to your gas valve, remove the aluminum 1/4" pilot tubing at the valve and start furnace , when spark starts you should smell gas coming out of the valve or even feel the gas, if you get air , you would need to crack the union on the gas line near the furnace to purge air from your line.There should be no reason to check the pressure switch, as it's sending a signal to the spark ignitor.Is this the first time you used it or it was working fine this year till now? Reason for asking , is if a system sits all summer , never used sometimes they need to be purged of air,the first time.You do not say if you actually have a pilot flame either you say "and ignition start" What does that mean, you actually have a pilot or it tries to light the pilot.

---------- FOLLOW-UP ----------

QUESTION: Sorry Joseph, I could have been clearer in my description. I have a Hot Surface ignitor and the furnace has been working fine.  I just got back down out of the attic.  

With thermostat set above room temp, I pulled the compartment doors and held the door switch closed.  The draft inducer fan starts, the control board has both lights on and the ignitor is not coming on but I could smell propane.  I disconnected the ignitor pigtail, energized the system and read 120 volts across the leads going to the ignitor from the control board with my multi-meter. The ignitor must be dead I guess. What confused me was the circulation fan coming on, I always thought if no ignition took place the unit would go into lock-out and that the fan would not come on.

Thank you for your help, you guys are great to give your time like this.  I'm a member of an automotive site that does the same thing to help other techs and such.  Why these things always seem to happen at the most inopportune times I'll never know! I'll send you some holiday cheer when I get a chance.


Your model, circulator fan uses a time delay relay to start the fan, even if heat does not work it will come on. Look at the wiring diagram, it may show the fan relay listed as TDR  ( time delay relay ).You should carry a spare glow coil, thay are miimal cost ,if you plan on keeping your furnace for years to come.If your system has a flame sensor , try manually lighting using a long stick in the general area of the flame sensor ( your comment I can smell propane ) that should at least give you some heat till you get your parts.

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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