Gas Backup power didn't back us up!

[Pilot]

We have gas water heater and gas furnace. Lost power for 5 hours a few days ago. Fired up the generator, hooked it up as usual and the furnace fan ran as usual, but the gas in the furnace didn't fire up. And the fan blew cold air. Water heater didn't fire up either. Checked the propane tank & it was at 55%. The way our system has always worked was when we fired up the generator, the furnace fan blew air, the burner came on and all was nice & toasty. The water heater doesn't need electrical power so the gas should heat the water but it didn't.

But when the power came back on both units fired up by themselves and we magically got both warm air and hot water!

What kind of failure could account for both systems to quit, but worked fine when the power came back on?

 

[kcflhrc]

Regulator froze up

 

[void777]

Generator not putting out electric.

 

[Jstpssng]

Propane generator? If so there may not be enough fuel in tank to run the generator along with everything else, or more likely the regulator isn't adequate.

 

[Chilliwack Murray]

It doesn’t explain the hot water if that truly has no electrical connection but our newer high efficiency furnace won’t open the gas valve if the neutral is not grounded (as is the case on most portables).

If determined the cause by the indicator lights on the furnace control board flashing out a code and looking up the code on google.

If the gen and the appliances are both fed from the same propane supply my guess is there was insufficient pressure either from the regulator freezing as the previous port suggests or the tank pressure was too low with the generator running and low ambient temperature.

 

[CADplans]

You don't really say how the generator is hooked up,,,

The furnace could be operating from two different circuits,,, and possibly you only have one of those on the generator switch over,,,

 

[MossRoad]

We have gas water heater and gas furnace. Lost power for 5 hours a few days ago. Fired up the generator, hooked it up as usual and the furnace fan ran as usual, but the gas in the furnace didn't fire up. And the fan blew cold air. Water heater didn't fire up either. Checked the propane tank & it was at 55%. The way our system has always worked was when we fired up the generator, the furnace fan blew air, the burner came on and all was nice & toasty. The water heater doesn't need electrical power so the gas should heat the water but it didn't.

But when the power came back on both units fired up by themselves and we magically got both warm air and hot water!

What kind of failure could account for both systems to quit, but worked fine when the power came back on?

You said you have a gas water heater and a gas furnace, but you didn't say if they were natural gas, or if they were propane.

You said you have a generator and fired it up and hooked it up usual, but you didn't say if the generator is propane, natural gas, gasoline, or diesel powered. Also, what does hooking up the generator as usual entail?

You said you checked the propane tank and it was 55%, so we know you have propane, but we don't know what all runs on propane.



So....

A little more info would be useful for troubleshooting. :thumbsup:

 

[zzvyb6]

So, pull the main breaker, get the generator on-line again and see if the same symptoms appear. If so, then your transfer switch, feed, neutral or ground wiring is the culprit. Furnace fan would probably be 120v. Gas coils from another circuit that's not enabled ?

 

[TheMan419]

Generator not putting out electric.

He said the fan on the furnace was running.

 

[RalphVa]

Are your pilot lighters on the generator?

Ralph