Freezing and furnace problems

[Witch Doctor]

Originally Posted by jonwisconsin

Another suggestion, if you are going to experience freezing temps, keep the grey valve open and a dripping faucet until the temps get better. I have done this for years to avoid problems.

I have been to alot of CG's that have rules on that and if caught they will throw you out, and on the other hand I have been to some that tell you to do it, thats only because they do not want there supply system to freeze up, best always to check.....

[A32Deuce]

Originally Posted by phfkef

We use propane all winter to BBQ, heat homes etc... It goes way below freezing.

The bigger the tank the lesser the problem.

[HangDiver]

Originally Posted by phfkef

We use propane all winter to BBQ, heat homes etc... It goes way below freezing.

I believe the pressurization to run the furnace is different than to run a grill. I'll bet the OPs stove top worked while the furnace didn't.

[Cypressloser]

Originally Posted by HangDiver

I believe the pressurization to run the furnace is different than to run a grill. I'll bet the OPs stove top worked while the furnace didn't.

All typical propane household appliances like bbq, gas range, furnace and water heater all run on the same pressure of around 0.4 psi.

[rockfordroo]

Originally Posted by HangDiver

I believe the pressurization to run the furnace is different than to run a grill. I'll bet the OPs stove top worked while the furnace didn't.

Originally Posted by Cypressloser

All typical propane household appliances like bbq, gas range, furnace and water heater all run on the same pressure of around 0.4 psi.

They may run on the same pressure, but when it gets cold, the vaporization of liquid to gas slows down and if it gets too cold and slows down too much, it can't keep up the pressure. If the furnace is asking for a greater flow of gas than the vaporization can provide, the pressure is going to drop. So in the end, both pressure and flow become inadequate.

Note that the regulator can only control pressure if the vaporization rate is greater than the usage rate.

[jeff64]

If, you had a manometer hooked up and you had a couple gas appliances operating, you would still show an 11" W.C. on the manometer if all is functioning together, properly. That is regulator, vaporization rate of Lp. Vaporization affected by temperature, surface area of liquid and volume of space in tank above liquid.

[Cypressloser]

Originally Posted by rockfordroo

They may run on the same pressure, but when it gets cold, the vaporization of liquid to gas slows down and if it gets too cold and slows down too much, it can't keep up the pressure. If the furnace is asking for a greater flow of gas than the vaporization can provide, the pressure is going to drop. So in the end, both pressure and flow become inadequate.

Note that the regulator can only control pressure if the vaporization rate is greater than the usage rate.

Correct, but this shouldn't be a problem down to around -40F/C, even for the small 2 stage RV style pressure regulators when it is pure propane and not a propane/butane blend.
Maybe the OP simply has a malfunctioning pressure regulator....?

[MR.M]

Originally Posted by phfkef

We use propane all winter to BBQ, heat homes etc... It goes way below freezing.

it's a bit different in a home for one larger dia supply lines , larger tanks giving full pressure until it hits the regulator which is normally mounted just outside the home . in my case my 500 gallon tank is buried which keeps the propane warm

[jeff64]

Originally Posted by rockfordroo

They may run on the same pressure, but when it gets cold, the vaporization of liquid to gas slows down and if it gets too cold and slows down too much, it can't keep up the pressure. If the furnace is asking for a greater flow of gas than the vaporization can provide, the pressure is going to drop. So in the end, both pressure and flow become inadequate.

Note that the regulator can only control pressure if the vaporization rate is greater than the usage rate.

True, and if equipped with auto change over regulator, and is engaged. The feed will switch to the alternate tank and operate as long as/ and until the conditions in that tank meet the parameters to maintain the 11" WC or can't.

[rockfordroo]

Remember also that regulators tend to freeze up if there's any moisture at all in the LP gas.

[RVJeeper18]

Not to derail, but I have similar problem! 2017 Coachmen Leprechaun 317SA and I cant get my furnace to do anything... According to the furnace owners manual and the tech at the dealer (called them) - there should be a separate furnace switch somewhere (tech though it would be on base board under couch, fridge, or oven?) but I can't find it?

Furnace Instructions have the following complicated sequence (or something close, running from memory) - but have never heard of anyone having to go through all this?
Turn off gas at tank and turn off switch
Put thermostat in heat mode and the fan in the furnace should come on to blow out any residual gas (run 1-2 minutes) then turn off.
Turn on gas and switch
Set furnace to heat and it should fire up

I can't find a switch and no matter what sequence I do I have not been able to get the furnace to do anything. Can't get the evacuation fan to kick on or anything else.

Anyone have this same MH and know where the "switch" is?
Do I really have to go through all that sequence just to turn on furnace?

Any help appreciated....

[HangDiver]

Originally Posted by Cypressloser

All typical propane household appliances like bbq, gas range, furnace and water heater all run on the same pressure of around 0.4 psi.

Thanks!

[jegstrup]

Originally Posted by RVJeeper18

Not to derail, but I have similar problem! 2017 Coachmen Leprechaun 317SA and I cant get my furnace to do anything... According to the furnace owners manual and the tech at the dealer (called them) - there should be a separate furnace switch somewhere (tech though it would be on base board under couch, fridge, or oven?) but I can't find it?



Furnace Instructions have the following complicated sequence (or something close, running from memory) - but have never heard of anyone having to go through all this?

Turn off gas at tank and turn off switch

Put thermostat in heat mode and the fan in the furnace should come on to blow out any residual gas (run 1-2 minutes) then turn off.

Turn on gas and switch

Set furnace to heat and it should fire up



I can't find a switch and no matter what sequence I do I have not been able to get the furnace to do anything. Can't get the evacuation fan to kick on or anything else.



Anyone have this same MH and know where the "switch" is?

Do I really have to go through all that sequence just to turn on furnace?



Any help appreciated....

They are maybe referring to the reset switch? Mine is located in the furnace and is very visible when you remove the outside cover.
But, no, you shouldn’t have to go thru this sequence every time you start the furnace. I just switch my thermostat to furnace to start it

[kholmes]

We had a similar problem last year when we were heading down to Arizona from Saskatchewan at the end of Dec. We discovered the regulator was froze up and not allowing the propane through to any appliance. Temps when we left Canada was minus 20 Celsius. Cold temperatures have major effects on propane usually because of moisture in regulators and tanks.

[RVJeeper18]

We are in South Texas, so not cold enough to freeze the system - only in the low 50's. Propane is 3/4 full. Checked the reset switch and it looked ok - switched off and back on and got a red light that blinked on the board, continued to blink every 5-10 seconds.

Any other ideas?

[MR.M]

Originally Posted by RVJeeper18

We are in South Texas, so not cold enough to freeze the system - only in the low 50's. Propane is 3/4 full. Checked the reset switch and it looked ok - switched off and back on and got a red light that blinked on the board, continued to blink every 5-10 seconds.

Any other ideas?

count the blinking lights they will give you a code you should be able to check , codes s/b on the blower motor cover and it will tell you what's wrong . also you need to power off for about a minute to get a full reset

[RVJeeper18]

Got it fixed! Dug around on google and found phone number for Coachmen corporate Service rep. They called me back in 20 minutes and 1) Told me to forget about another "switch" (does not exist..) and 2) walked me through some diagnostics and determined they thought it was bad Ignitor circuit board. It is a very universal part and local RV shop had one in stock - easy to swap and works like a champ!

Thanks for the help.

[nomad297]

Originally Posted by RVJeeper18

Got it fixed! Dug around on google and found phone number for Coachmen corporate Service rep. They called me back in 20 minutes and 1) Told me to forget about another "switch" (does not exist..) and 2) walked me through some diagnostics and determined they thought it was bad Ignitor circuit board. It is a very universal part and local RV shop had one in stock - easy to swap and works like a champ!

Thanks for the help.

Did anybody take my bet?

Bruce

[RVJeeper18]

Originally Posted by nomad297

Did anybody take my bet?

Bruce

They should have! I read through the entire thread but somehow missed your comment on the circuit board.... Would have sure saved me some time and grief from the wife....

[Witch Doctor]

Atwood has a real problem with the China water heater board, but to be honest this is only the second problem I heard of with the FAU board, one was from Arron and his got wet some how. He sired it off and got it going again. With this being said winter is just beginning, I hope nobody else has this problem. I keep a spare water heater board that I bought for 40.00 dollars at the salvage yard in Goshen
Mine was brand new and only worked for 3 days. I hope mine holds up if not I will get the dinazore board made in the USA. Atwood has a real problem with those CHEAP Chinese boards they use. Glad you you got yours running again.

Originally Posted by RVJeeper18

They should have! I read through the entire thread but somehow missed your comment on the circuit board.... Would have sure saved me some time and grief from the wife....