Furnance Issues

[mlyon]

Just got back from our trip in our Motorhome 37c Southwind.  Notice 3 last 3 nights when the temp got down in the 30's the furnance would make the sound that it was trying to come on but it never did because it would just blow cold air.  After serveral attemps (that clinking on and off) I finally would shut off the furnance.  I would only do this when it got real cold. The last couple of nights in  the 30's so it would start not working and doing that clinking on and off at around 3:00am.  The last night it only got down to the 40's so it didn't start that clinking on and off till 5:30am.  When it warmed up (9:30 on the colder nights and 7:30am when it was in the 40's) The furnance came on no problem. And stayed on and warm up fine.    Its not the propane we had half a tank. 20 gallon tank.  Filled it up before we left.  And today when we came home filled it up and it only took 8 gallons.  Asked the gentleman that filled up the tank what kind of problems we were having and its not because out LP was too low.  Like I said.  It was only in the middle of the night and early morning when It was cold out. 

On one of those nights I got up and tried to light the stove and it would surge (the flame on the stove) everytime the furnance would try to light.  By that I mean it would come on sort of high (but not really) and then go real low as if it was going to go out) The switch for the water heater even lit up.  But only because the furnance was trying to come on.  The furance other than that worked fine after it warmed up a little outside.  The water heater had no problems staying lit.  Checked to make sure the vent in the regulator was not blocked.    Any helpful suggestions would be great. 

Mlyon

 

[Karl]

Mlyon,

Based on what you said about the flames going lower when the furnace tried to start, that would lead me to think either regulator or clogged LP lines. Even though you checked for blockage, there might be a little frozen moisture inside the regulator, preventing it from operating properly. You might try placing a small (15-25 watt) light bulb beneath it for a few hours to evaporate it. That failing to solve your problem, a regulator replacement is pretty easy, and they don't cost more than $8-10. You didn't say how old your rig is, but the lines can become clogged after a period of time. Not having done it, I can't tell you how to clean them , but surely someone else can. Good luck!

 

[Gary RV_Wizard]

First of all, do you have a heat pump a/c system? If so, you may have the automatic system where the heat pump will heat the place until somewhere around 38 degrees and then auto-switch over to furnace. That might explain the temperature dependence. Regardless, there is still the issue of the furnace not lighting.

Propane does not vaporize as well in cold temps, but 30's isn't cold enough to be a real problem and it should light and run fine. However, if your LP pressure is marginal to begin with, maybe the cold is enough to be a problem.  That should affect other appliances too, but the furnace demands a lot more propane flow than any other appliance in the RV and maybe would fail first?  I would suggest a pressure test - or maybe just go ahead and replace the regulator - that probably costs no more than a test (unless of course you have your own manometer). Another possibility is oil/water/sludge in the regulator or propane lines. That can happen if the tank runs low and you suck up crud from near the bottom. A glob of sludge can stick in a line or orifice and prevent an appliance from working while the rest of the system is fine.

Last, the electronically-controlled propane valve on the furnace could have failed, either the valve itself or the circuit board function that opens it.

 

[Gottasmilealot]

It sounds like you're not getting the intended propane flow for some reason, either the regulator or a partially blocked line. You may have enough gas flow to operate any one of the 3 (range, furnace, or water heater) but not more than one.  Perhaps what is happening is that the furnace will not light if the water heater is burning.  When the water heater burner shuts down, then the furnace lights... which probably happens more the colder it gets. Be sure your tank valve is open all the way, check the lines, and the regulator, as has already been suggested.  Light several range top burners, then turn you thermostat up so the furnace comes on, and it probably won't light.  Hopefully it's as simple as your tank valve not being fully open.

 

[mlyon]

Wow.  Thanks for all the quick imput.  Yes we have a heat pump/ac.  Our motorhome is a 2006 and we have had it for 3 months.  First time using it in cold weather for us.  We filled up the propane for the first time the Saturday before Chirstmas when we left.  It was previously filled by the dealer when we bought it.  Please explain the heat pump.  When we took it out for Thanksgiving a more experierced neighbor camping next to us got to talking with us.  I had told him how I had the electric heat on and when we got back from an outing that night the electric heat was blowing nothing by cold air so I put in on gas heat.  The more experieced neighbor says that when it gets below a certain temp that the electric heat doesnt work well.  Anyways.... I havent used it since. Electirc heat that is.  Anyways... Im rambling..  Want to address the issue with the gas heat and furnance right now.  The darn thing only had problems when the motorhome was really cold and when it was cold outside.  Did I mention our fresh water hose froze?  If I have a choice between no water or no heat.  I pick no water.  But when its cold outside I WANT HEAT!.    So any advise would be great. 

The darn problem is where we were had no phone reception to be able to call someone an ask while we had our motorhome out and operational.  So everything that is suggested has to be tried the next trip out.

Mlyon

P.S.  How often should you replace a regulator?  Our motohome is new.  but I know that doesn't mean anything.  We have had other issues.  With all of them have been resolved.  This is just a new issue.    So again any help would be great!

 

[Lowell]

I don't have a clue about the furnace but if you leave your water running at a trickle, the water line won't freeze up.  At least that was our experience when we were camping for several nights at 18 degrees F. This assumes you aren't boondocking and the excess water is draining into the sewer systems, not your grey water tank.

 

[Karl]

A heat pump is actually the air conditioner working in reverse. It extracts heat from the outside air and transfers it to the inside. Unfortunately, they stop working when the outside temp. gets into the 30's, so you need to use your propane furnace(s). Also, the heat pump distributes the heat inside the coach and does nothing to keep the outside water lines, water pump, and tanks, from freezing. The propane furnaces USUALLY do that. Unless damaged or clogged, a regulator should last many years - it's not a regular maintenance item.

 

[Gary RV_Wizard]

There are three possible ways to that an RV may be heated (not counting portable auxiliary heaters, either electric or propane):

1. LP gas furnace
2. Air conditioner with electric heating strips
3. Heat pump

The a/c with heat strips is just an electric heater mounted in the a/c air outlet, so it is not sensitive to temperature. A heat pump, however, is unable to pump heat from the outside air if that air is too cold. Rv heat pumps generally cease to function around 38-40 degrees. Many RVs with heat pumps will automatically start the LP gas furnace  when that happens, but some require manual intervention. For the future you need to figure out whether you have a heat pump or heat strips.

By the way, most RVers carry at least one portable electric heater - they do a dandy job of heating a small space and are much quieter than an LP furnace. Don't burn up your expensive propane either.

 

[mlyon]

We have a HEAT PUMP. And we also have a portable heater.  I just want to use our furnance and its not working properly.  So any help would be great....

We have a heat pump not heat strips.  And I pretty sure we have to manually change the thermostat from electric heat to gas heat even with a heat pump.

Mlyon

 

[Gary RV_Wizard]

So everything that is suggested has to be tried the next trip out.

Why is that? Don't you have access to the coach between trips?

Sorry to muddy the waters with the heat pump question, but it's about the only thing I could think of that might affect the furnace operation at the temps you described.

The other possibility I cited is that a propane line or the regulator is partially clogged with an oily sludge that sometimes forms in the bottom of the LP tank. Conceivably the clog becomes more solid in colder weather and becomes enough to reduce LP flow to the furnace. A furnace uses a much higher propane flow rate than anything else in the RV, so it is a bit more sensitive to propane flow. I've never heard of such a clog being temperature dependent, but then one only uses the furnace when it is cold.

Last, were you plugged into shore power when this happened or were you on batteries?  If on battery only, battery voltage may have dropped low enough to inhibit ignition. We tend to use more 12v power ona cold night when huddling inside, so a marginal power situation is exacerbated.

I'm kind of clutching at straws here, because your symptoms are unusual, to say the least.

 

[Karl]

Another VERY REMOTE possibility is that someone put Butane in the tank instead of Propane. I don't believe the fittings are the same, but people have been known to do some pretty unusual things. Butane stops changing from liquid to vapor at a much higher temperature than propane, so gas-fired appliances will not work as well or at all in cold temperatures. Let me repeat - Very remote, but not impossible.

 

[mlyon]

We were plugged into shore power.  So its not a battery issue.  Our motorhome is at storage about 40 minutes from our house.  We can not park it on our street as it is not wide enough to take that chance. It could go on our yard but then its over the sidewalk.  So this only will happen when we are washing it.  As for something I'm going to try. The oil sludge build up very much sounds like it could be our problem. Since a regulator is not a warranty issue then the black line that connects it to our motorhome on the other side isn't a warranty issue if we got bad propane (per fleetwood)  I went to storeage today to put in the clean laundry and bedding back in it and checked the LP hose line to see how accessable it was.  Its very.  So I'm going to remove it to see if oil has built up in that.  If so I'm going to replace it.  If that doesn't work then replace the regulator.  If that doesn't work.  Then I will contact fleetwood and then the dealer.    Fleetwood told me today that if its bad LP then that isn't a warranty issue.  We only filled it up 1/2 tank before we left this trip since we got it.  And we filled it up where they recommend us to. But can't prove anything.  but how do we know if it wasn't the propane that they put in it.  Anyways. Another forum reading issues with  LP furnace someone mention to someone about oil that sometimes builds up in the LP tank getting thicker when it gets cold and lets less LP through the line.  Since we are only have problems when its cold out 30's or 40's and then we it starts to warm up its fine.  I'm going to check the hose first.  I will keep you posted.    And no we did not get butane instead of LP.  Like I said we have only put 9.4 gallons in our tank to fill it since we bought it (came with a full tank) just before we left this time.  Then it acted up.

The best part of it is I don't have to deal with the dealership.  Something that can be fixed by ourselfs.  I will keep you posted.

 

[BruceinFL]

Wow.  Thanks for all the quick imput.   Yes we have a heat pump/ac.   Our motorhome is a 2006 and we have had it for 3 months.  First time using it in cold weather for us.  We filled up the propane for the first time the Saturday before Chirstmas when we left.  It was previously filled by the dealer when we bought it.  Please explain the heat pump.   When we took it out for Thanksgiving a more experierced neighbor camping next to us got to talking with us.  I had told him how I had the electric heat on and when we got back from an outing that night the electric heat was blowing nothing by cold air so I put in on gas heat.   The more experieced neighbor says that when it gets below a certain temp that the electric heat doesnt work well.  Anyways.... I havent used it since. Electirc heat that is.   Anyways... Im rambling..   Want to address the issue with the gas heat and furnance right now.   The darn thing only had problems when the motorhome was really cold and when it was cold outside.   Did I mention our fresh water hose froze?  If I have a choice between no water or no heat.   I pick no water.   But when its cold outside I WANT HEAT!.    So any advise would be great. 

The darn problem is where we were had no phone reception to be able to call someone an ask while we had our motorhome out and operational.  So everything that is suggested has to be tried the next trip out.

Mlyon


P.S.  How often should you replace a regulator?  Our motohome is new.  but I know that doesn't mean anything.  We have had other issues.  With all of them have been resolved.  This is just a new issue.    So again any help would be great!

If your motorhome is new, the regulator and the system should be under warranty. Why mess with it yourself? Take it into a dealer and get it fixed.

 

[Gary RV_Wizard]

Yes, oil can clog a regulator or gas line. No, it's not likely in a new RV or from any one tank refill. And no, you don't need butane at those temps. Chances are the propane was a blend anyway, designed for the region where you bought it.

You may not be able to visually determine if there is gunk in the line - might have to blow it out to see. But you can disconnect the regulator and flex line and see if anything is apparent. If you see black gunk, you have found the problem. But if you don't see any gunk, you aren't  really much wiser than before.

 

[mlyon]

Right if we don't see any gunk when we remove the line.  Then we are taking it to the dealer.  An to the person who said if its new its under warrenty.  Thats not what fleetwood told me.  I called them first.  And yes our motorhome is new.  I think it has 580 miles on it.

 

[Gary RV_Wizard]

An to the person who said if its new its under warrenty.  Thats not what fleetwood told me.  I called them first.  And yes our motorhome is new.  I think it has 580 miles on it.

??? Fleetwood said your new rig has no warranty? And you are the first owner of new coach?  Or did they say that the problem you have is not covered under warranty?

 

[mlyon]

We are the first owner.  Fleetwood said the regulator is not a warranty item.  And if it bad LP that is not a warranty issue also.

Mlyon

 

[Ned]

I can see Fleetwood refusing to replace under warranty if you actually did get bad propane, but if just failed, and it's less than a year old, it should be taken care of.  Check your paper work, perhaps the regulator has its own manufacturers warranty.

 

[mlyon]

1/2 tank of propane! Thats all we filled it when it acted up.  I guess Im going to have to get down right angry with them and refuse to pay one cent because its too new to have any problems that shouldn't be taken care of by the dealer/mfg.

Mlyon

 

[Marc L]

It won't help your problem, just some additional info.  Propane can flow at much colder temps than what they were when you were experiencing the problem at.  I have a propane fireplace in the house (tank outside) and it works fine at temperatures below 0F.

I normally try to solve things by process of elimination, so you can cross low temperatures off your list.

Like you said though, on a new unit like this, the dealer should take care of it even if only to keep you happy and make sure you and your buddies buy your next RV from them.