Skip to content
Forum Scope


Match



Forum Options



Min search length: 3 characters / Max search length: 84 characters
Forum Login
Lost password?
sp_TopicIcon
Furnace not firing
Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
1
October 25, 2011 - 8:24 am
Print

Furnace isn't firing and I'm not sure why?

Propane:
1. I opened the propane tank slowly to make sure the check value didn't block the line.
2. Then, light the stove and burned it for 5 minutes with a solid flame to make sure there wasn't air in the line.

Electric:
3. I'm plugged into shore power so I don't have to worry about the battery being drained and not having the 12v.
4. I made sure the gallery was raised so the safety switch would be applied and the camper would have power.
5. The verified all the breakers were on and not tripped in the electrical panel.

Thermostat:
6. I turned the thermostat switch to the on position.
7. Then set the temperature much higher than the current temp in the camper. I can hear the mercury shift and spring expand

Within about 20 seconds, you furnace kicks on (blower) and several seconds later, a clicking noise (igniter) to start the furnace but it won't fire and only blows cold air.

8. I removed the cover and verified the breaker switch under the cover was on.
9. I put a meter on the terminals and verified 12v
10. I removed the ignitor and verified that I'm getting spark.
11. I removed the burner, ignitor and circuit board to blow everything off with a can of compressed air.

NO LUCK!  ???  Any thoughts on other things to test before I need to pay a dealer?
[smg id=511]

[smg id=512]

[smg id=514]

[smg id=515]

[smg id=516]

[smg id=517]

Avatar
349 Posts
(Offline)
2
October 25, 2011 - 9:58 am
Print

Have you verified that the wire from the thermostat to the furnace is intact? We had a similar issue last fall with our Flagstaff -- thermostat appeared to be functioning, furnace blower would come on and ignitor fired but would not light. I finally found that the wire from the thermostat was broken from being pinched when the galley was raised and lowered.

If the factory would have used two more wire ties and one or two more grommets we never would have had the problem. Of course, the same thing could be said for a number of things on that camper!

John

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
3
October 25, 2011 - 11:51 am
Print

I assume that the thermostat is wired and intact because I can turn the furnace on and off by both the thermostat on/off switch and raising/lowering the temperature.

I don't know is there is an easy way to test the propane pressure (don't think that's a problem), the sail switch?, etc.

I'd like to start the burn outside of the furnace so I know it's not a propane or burner issue but I'm not sure of the flame size and would like to not burn down the camper. 😮  I have a few trips planned.

Avatar
2545 Posts
(Offline)
4
October 25, 2011 - 12:15 pm
Print

If you hear it clicking on and off and you know you have a spark, I would think it is a gas issue.  When you had the piece off that the propane line goes into, did you turn the gas on?  If you don't have gas coming out (good old sniff test) of the line, there is your problem.  If gas does come out then I don't know. 

Just remember, extinguish all cigarettes, cigars, and pipes prior to checking the gas.

Matt O 2006 Skyline Nomad 27' travel trailer.  Previously owned 1986 Coleman Columbia / 1992 Coleman Senecca / 1989 Born Free Class C RV.

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
5
October 25, 2011 - 12:40 pm
Print

Thanks for the disclaimer.  😉  I did open the propane tank and can smell gas at the line when its disconnected.

There is a circuit board, sale switch and safety sensor that I know nothing about or how to check/bypass.

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
6
November 14, 2011 - 9:34 am
Print

After some additional testing, I'm happy to say that the furnace is fixed.  $24 for a new low pressure regulator.  We lite one burner and things looked good and then when lighting the next burner, the flame for both got lower like there wasn't enough gas to supply them.  When you light the furnace, they all went out.  It appeared that the problem was propane related and not the furance.

I purchased a new low pressure regulator and gas fitting tape (yellow).  I removed, cleaned and taped all connections.  See picture below.  Everything works great.

[smg id=646]

Make sure you use propane tape and not plumbing Teflon tape. (use the yellow stuff)
[smg id=645]

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
7
March 4, 2012 - 6:14 pm
Print

Opened her up today and started spring cleaning, the heater is blowing cold air.  Errrrrrrrr  :tickedoff: I guess it's not fixed. :banghead: :knuppel2:

Avatar
236 Posts
(Offline)
8
March 4, 2012 - 6:16 pm
Print

[quote author=Lone Lock link=topic=1177.msg8966#msg8966 date=1319559315]
If you hear it clicking on and off and you know you have a spark, I would think it is a gas issue.

/quote]

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
9
March 4, 2012 - 7:18 pm
Print
    [li]I'm getting propane to the stove, past the furnace.[/li]
    [li]I have 120v electric to the camper[/li]
    [li]I have 12v to the furnace[/li]
    [li]The thermostat starts the furnace[/li]
    [li]The blower kicks on and blows cold air[/li]
    [li]The ignitor starts clicking after a few seconds[/li]
    [li]... and nothing but cold air.[/li]
Avatar
2545 Posts
(Offline)
10
March 4, 2012 - 9:19 pm
Print

I still say everything seems to be pointing to a propane issue.  If the stove is after the furnace and the stove is firing, then I would say the issue is between the T and the furnace.  I know with gas fireplaces spiders  screw them up with their webs often.

Personally I would unhook the line at the furnace and then turn the gas on so it blows anything out.  Or you could unhook the line at the T and the furnace and blow it out with air.  If you find that nothing is coming out then you know that line or T needs to be replaced. 

disclaimer.....I sit at a desk all day doing paperwork, I am not a plumber, RV tech, or electrician.

Matt O 2006 Skyline Nomad 27' travel trailer.  Previously owned 1986 Coleman Columbia / 1992 Coleman Senecca / 1989 Born Free Class C RV.

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
11
March 4, 2012 - 10:29 pm
Print

There maybe a few less ralies if I blow up!  :blink1:

A few other thing to consider:
1.Sail Switch
2.Limit Switch
3.Relay
4.Circuit Board
5.Air Speed Indicator
6.Propane PSI Level (U-Tube Manometer)

Avatar
666 Posts
(Offline)
12
March 5, 2012 - 8:01 am
Print

I'd put my money on a bad sail switch...

Avatar
236 Posts
(Offline)
13
March 5, 2012 - 5:50 pm
Print

I spoke to Joe as well and I also think the sail switch is faulty.

Avatar
666 Posts
(Offline)
14
March 6, 2012 - 8:23 am
Print

5.Air Speed Indicator

Hey Joe,
How fast does that pup fly???? ;D

Avatar
550 Posts
(Offline)
15
March 6, 2012 - 9:21 am
Print

We had a similar (I think) problems twice with the furnace of our camper ...only blew cold air. propane to fridge and stove worked fine.

The first time, it was the propane line that somehow got crimped and wasn't allowing enough gas to flow to the furnace - dealer fixed that one as it was a new camper on it's first trip.

the second time it was the switch of the thermometer - one of the wires was damaged.

Joe - - be a Avalon is looking better and better all the time  😉

Avatar
217 Posts
(Offline)
16
April 1, 2012 - 8:44 pm
Print

This is just the PUPs way of saying Happy Birthday. It wants some quality time with you. I haven't had much experience with the heater yet, but I will say from my experience outside and heating equipment, electronics can drive you mad and can be the simplest fix.

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
17
April 17, 2012 - 4:29 pm
Print

Yeah,  :thumbsup: the propane and furnace issues are fixed.  Apparently the high pressure regulator was failing at times but not all the time.  It is done now, removed from the system and things are running great.  The propane line ran from the tank through the high pressure reg, T'd off for the outside stove, through the low pressure reg and out through the camper's water heater, refrig, stove and furnace.  I ran them all at the same time last evening and everything works great.

I'm going to purchase a new high pressure reg and install it even though it's only for the outside stove and I don't use it anymore.  I don't want to change the features originally available with the camper.
[smg id=925]

Avatar
349 Posts
(Offline)
18
April 17, 2012 - 4:44 pm
Print

So, how did you finally nail it down?

Bet you're glad it's fixed, since it was 87 degrees here in central PA yesterday!  ;D

John

Avatar
Eastern Pennsylvania
3873 Posts
(Offline)
19
April 17, 2012 - 6:09 pm
Print

I only need it now for the water heater since there's no need for heat and the frig runs on electric.  Either way it needed to be fixed and we camp through November so cooler weather is coming later.

I originally was planning to disconnect both ends of the propane line and blow it out with a compressor thinking maybe there was condensation or spider webs in the line.  Not sure how spiders would get in a closed system but wanted to clear it either way.  When disconnecting the regulators, thought I try to bypass the high pressure one and test it once.  Worked great and now the regulator rattles like a spring or something is broken inside.

Forum Timezone: America/New_York
All RSSShow Stats
Administrators: CampingPhil, JoeCamper
Forum Stats:
Groups: 6
Forums: 70
Topics: 3700
Posts: 37115

 

Member Stats:
Guest Posters: 3
Members: 2689
Moderators: 0
Admins: 2

Most Users Ever Online
769
Currently Online
Guest(s)
238
Currently Browsing this Page

1 Guest(s)