No heat (again)

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No heat (again)

March 02, 2014, 09:47:48 pm

It is down to 7 degrees out, headed to a low of 1, and neither furnace is producing any heat. The rear furnace, new this fall, does nothing. The front one just blows cold air. I'm going to leave them on just in case they get going again, but I'm also going to turn on the rear heat strip. Doors under the sinks are open, and I'm hoping that enough heat will get down below to keep the plumbing from freezing. Tomorrow I'll see what I can see. Sure hope I don't have to take this thing back to Phillipsburg for another new furnace - the roads are NOT good.

Re: No heat (again)

Reply #1 – March 02, 2014, 09:59:11 pm

Sounds like you might think of draining the low point drains and the water heater if nothing is working or at least put some electric heaters in the basement to keep the water pump and lines from freezing. I don't think the overhead heat will provide any heat to the basement plumbing. How much propane do you have? Will the cook stove light so that you know you have propane? At 1 degree will not take long to freeze things and break pipes. Have you turned the thermostats off and back on to see if that will reset the circuit boards on the furnaces?. On the rear furnace check that it has 12 volts getting to the furnace by removing the outside cover to see it has 12 volts

Re: No heat (again)

Reply #2 – March 02, 2014, 10:08:34 pm

Are you getting propane anywhere? Your coach probably has or had a gas shutoff solenoid valve connected to the gas sniffer.

How strong is your 12 volt power to the furnaces? If you still have the original converter charger, some circuits connect to the battery all the time, while other circuits have power routed through a relay from the AC/DC converter when ac power is present.

I really can think of only two likely reasons for both furnaces to act this way at the same time, low voltage or no propane. A bad sail switch on both at the same time is somewhat unlikely.

Re: No heat (again)

Reply #3 – March 02, 2014, 10:10:14 pm

I have had water freeze in the propane tanks pressure regulator.

When filling the tank I hesr adding alcohol to the line before hooking it to the tank.

Mixes the water I understand with the propane.

New equipment seems hard to fail. No gas?

Heat gun? Diesel gen?

Most have never heard of water in the propane but it happened to me. Condensation?

A warm building unthawed it. Unfortunately

Bob

Re: No heat (again)

Reply #4 – March 02, 2014, 10:11:35 pm

Thanks, Red. Both furnaces run enough to blow cold air, so I know they have power. I've turned both thermostats off and then on again. The hot water heater (gas) works fine. The Audit system says 3/4 full, the gauge on the propane tank says a little over half.

I'm wondering if there is an electrical issue somewhere. Today the lights would flash and the inverter would scream whenever the furnace was running and the refrigerator came on. Unplugging the refrigerator for a second or two and then plugging it back in shut up the screaming and stopped the flashing. The battery chargers and inverter are all new within the past couple of months, but the batteries are old.

The water tank is full, but you are right, draining it would probably be wise. That ought to make a nice skating rink outside!

Re: No heat (again)

Reply #5 – March 02, 2014, 10:20:19 pm

I just went out and turned the drain valves. Nothing. I'm guessing that I'll have some frozen pipes to deal with soon. I don't have a PEX cutter or any repair parts, so looks like a trip to Lowe's will soon be necessary. What size clamps, etc. do I need?

Re: No heat (again)

Reply #6 – March 02, 2014, 10:20:30 pm

do you have a awl mart nearby that can sell you a small space heater?

Re: No heat (again)

Reply #7 – March 02, 2014, 10:21:05 pm

light bulb in bays beneath each one that you don't want to freeze?

Re: No heat (again)

Reply #8 – March 02, 2014, 10:45:11 pm

Heaters and fans with all cabinet doors open and furniture (couch) up to expose as much piping as possible. Put some heat on the holding tank exposed piping as well. Keep an eye on things as they warm up, may have a broken pipe or fitting that has an ice plug in it. Have a great day ---- Fritz

Re: No heat (again)

Reply #9 – March 02, 2014, 10:55:59 pm

Last week I used 200 watt space heaters, one on each side of the wet bay. They were on thermocubes that worked from 38 on, to 50 off. When we had 10 degrees overnight, winds and snow, my lowest temps in the bays were in the mid 40's. We used three 1500 watt small space heaters in the coach and could make any temp we wanted in the coach in the mid 70's. We did not have to use the propane furnaces to be comfortable or keep from freezing the plumbing.

Re: No heat (again)

Reply #10 – March 02, 2014, 11:16:03 pm

My coach has an electric solenoid operated shut off valve on the propane tank hooked to a gas detector inside the couch. I believe the valve requires power to be open. (12V) I would check this even though the water heater is working. Does the stove work?

Re: No heat (again)

Reply #11 – March 02, 2014, 11:25:54 pm

Since you are plugged in, why not use several Walmart-type small space heaters?

We are at 20 degrees tonight and have 2 inside space heaters on low (about 800 watt setting) and one small radiator heater. In the bays we have four 200 watt 'Personal heaters'. We are drawing about 27 amp from our 50-amp shore cable. If our hot water tank comes on, it's another 12 amps. Electric refrigerator only draws 2 or 3 amps when running or defrosting. We are not using our furnace much. But I am sure the electric meter is spinning.

If a furnace fails to light 3 times, for any reason, the blower motor will continue to run, for no purpose. Once 3 sequential burner failures happen, the burners will not try again to light, until the furnace is turned off and back on. So it is much better to cycle the thermostat off and back on several times to clear out any air in the propane line or just to give the furnace another chance to light.

Re: No heat (again)

Reply #12 – March 03, 2014, 12:31:21 am

Quote from: kb0zke – March 02, 2014, 10:11:35 pm

Thanks, Red. Both furnaces run enough to blow cold air, so I know they have power. I've turned both thermostats off and then on again. The hot water heater (gas) works fine. The Audit system says 3/4 full, the gauge on the propane tank says a little over half.

I'm wondering if there is an electrical issue somewhere. Today the lights would flash and the inverter would scream whenever the furnace was running and the refrigerator came on. Unplugging the refrigerator for a second or two and then plugging it back in shut up the screaming and stopped the flashing. The battery chargers and inverter are all new within the past couple of months, but the batteries are old.

The water tank is full, but you are right, draining it would probably be wise. That ought to make a nice skating rink outside!

These indicators tell me the furnaces are seeing low voltage. I would check with a DVM at the furnace or if more practical at the fuse or circuit breaker that powers the furnaces. With low voltage, the fan motor runs, but not fast enough to open the sail switch which in turn opens the gas valve.

Re: No heat (again)

Reply #13 – March 03, 2014, 07:52:26 am

Agree- most likely culprit is low voltage.

So check at the house battery bank-- is it 12.5 VDC or higher (13 or higher if on shore power). If so the batteries are OK.

Next, check voltage at the furnaces-- should be within .2 VDC of battery voltage.

If both OK check for any obstruction in air return to furnaces and/or closed vents.

When air flow is insufficient, the SAIL SWITCH will not close and the furnace PC board will not turn on gas and igniter.

Re: No heat (again)

Reply #14 – March 03, 2014, 08:18:21 am

FWIW, Agree with Dave and Dolly, those small heaters (1500w) work great upstairs and basement those 200 watt heaters on a temp sensitive switch work great. I like the smaller ceramic type heaters as they take up less space. I have not used exclusively in really cold weather but did use to supplement the propane and the propane was not cycling in front. I had turned it down such that I was using the campground electricity but in rear was as I wanted to insure heat got down in basement. I did not really need but wanted "belt and suspenders" approach to cold weather. I believe it would work just fine.

Re: No heat (again)

Reply #15 – March 03, 2014, 10:30:35 am

I'm out here in the coach and it is toasty warm. We moved into the house last night just because it was cold out here. As we got into our sleeping bags I thought I heard the front furnace of the coach kick on, but at that point I wasn't interested in going out to see what was happening. Whatever the problem was seems to have cured itself. Strange.

The audit system is showing coach batteries at 13.4 VDC and 3/4 full on propane. The high for today is only going to be 22, but tomorrow it is supposed to get warmer, so maybe I can poke around a bit more then.

Re: No heat (again)

Reply #16 – March 03, 2014, 12:05:04 pm

This brings back memories of my 1988 sob motorhome with only a pair of group 27 batteries to power the house. Back then, the propane leak detector drew a couple of precious Amps day and night, and constantly provided power to a solenoid valve on the propane system.i am so happy the industry got away from these and went with low power units without a solenoid valve.

Each night while boondocking in cold winter, sometime in the predawn hours, I would wake to note the furnace has been running for a very long time, and the temperature is not in the least bit warm. Low voltage, low air flow, sail switch not letting the gas flow. I would get up, and turn the furnace off, then try to get the batteries charging so I could restart the furnace. But here was the trick part. The house battery at this time was too low to start the generator, the momentary boost switch might do it, but might not, and if I guess wrong and the voltage dips more from the generator starting or soneone else getting up and running the water pump, the propane sniffer will see the low voltage and noisily shut of the gas. So I cross my fingers and start the big engine, let it run a few ocessminutes, then start the generator, then reset the propane sniffer if needed, and finally start the furnace. Now I have heat for as long as the generator is running, but not much longer, as the old style converter charger has a very low rate of charge. Now to decide to keep the generator running or repeat the process a couple more times until morning and then run the generator to put some energy back into the batteries.

Oh how I miss that old sob. Not.

Re: No heat (again)

Reply #17 – March 03, 2014, 05:23:37 pm

Propane stops turning to gas at -44deg. but as it cools is boils off more slowly. Even so you should not have a problem. A frozen regulator would not allow the cook stove to operate at full power. This leaves the voltage problem or stuck sail switch. As both did not work I would bet on the low voltage at the unit.

BTW it's OK to gently heat a frozen regulator but not with an open flame (guess why?). Never heat a propane tank to get it to produce gas if the supply line after the regulator is below the boiling point of propane. The propane will condense back into liquid and feed it to the appliance. You won't have to worry about a cold RV if that happens folks. But then who camps at those kind of temps?

Keith

Re: No heat (again)

Reply #18 – March 03, 2014, 11:04:16 pm

My rear furnace ended up being a loose connection. Did what yours is doing. Several RV techs that I paid could not fix it. The Lennox furnace repair guy who work on my stick house found the loose wire and fixed it. He says that they are easy to trouble shoot and fix. You know who I'm calling from now on!

Re: No heat (again)

Reply #19 – March 03, 2014, 11:46:16 pm

I'm betting on the gas regulator. If the furnace senses low gas pressure, it will blow air but not ignite. At the age of our coaches the gas regulators are getting touchy. They can work one time and not the next. They are inexpensive to replace. Just make sure the replacement has the vent in the same place as the old one.

I sure hope you don't have broken pipes. We are heading back to Oklahoma tomorrow to fix broken pipes in our new cabin that I apparently did not winterize properly. Can you imagine leaving 80 degrees here in Tucson to go fix broken pipes. Next year I will do better. Let's hope the warm weather follows us.

Re: No heat (again)

Reply #20 – March 04, 2014, 09:27:49 am

Kent,

Sorry to hear about the pipes. I went from Nac to KC yesterday on 69. I cant tell you it was warm, but at least most of the main roads were in fairly good shape. Seems the heaviest snow was around Muskogee, if I recall correctly. BTW, the hunt continues

Larry

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