furnace..

[Christi V.]

I noticed my furnace was just blowing'air' the other nite..... the fan kicked on but no heat.. i was not outta propane... so is this a major repair or ??? I sure hope not!!

[Pamela H]

I noticed my furnace was just blowing'air' the other nite..... the fan kicked on but no heat.. i was not outta propane... so is this a major repair or ??? I sure hope not!!

Where you running on batteries or AC?

Pam

[Christi V.]

I aasume a/c as i was on shore power? it worked the last time I ran it.. so just baffled..

there was also a thread on water not staying in the toilet.... i seem to be having that problem again.. but couldnt find the thread.....

[Pamela H]

I aasume a/c as i was on shore power? it worked the last time I ran it.. so just baffled..

there was also a thread on water not staying in the toilet.... i seem to be having that problem again.. but couldnt find the thread.....

Doesn't sound promising...sounds like a trip to the furnace man...hopefully just part of your pilot system. Is the pilot lit? (always a good thing to check...)

[Harry Young]

I repair these...I need the model number...Many units have a three strikes to light feature and you get locked out of operation its built into their starting computers, when air is present in the gas line it might take as many as 6 or 9 striking attempts (thats 3 cycles) Note: (a cycle is three individual trys to light) before air is purged...the retry procedure is simple...turn the thermostat off wait for (BLOWER/FAN TO STOP!!!) then 5 sec after blower stops running...turn on the thermostat again, the computer will attempt 3 more times to strike up a flame then it will lock out from trying to light until you shut off thermostat and do this again...it is a feature required and designed into the operation of the unit, its a saftey lock out. I have had to do this up to 12 times before the air purged enough out of the gas lines for the flame to strike...This is my number one service call on Suburbons...Remember three strikes and your out and you must start over.

Often I purge the lines...thats a later idea and needs detailed instructions and saftey precautions...do this first.


Harry

Doesn't sound promising...sounds like a trip to the furnace man...hopefully just part of your pilot system. Is the pilot lit? (always a good thing to check...)

[Victor Benz]

Totally agree with Harry! That is why sequence of the gas start-up is so important.

1. Light a stove burner (It is always manual, an no thermocouple)
2. Light Hot water heater (manual light, but has a thermostat)
3. Light the refrigerator (pezioelectric light and thermocouple)
4. Now all gas lines should be purged of air, light the furnace.

Vic

[Shelley]

I'd like to piggyback on this thread....

I can get my furnace lit and have heat :-) But when painting the interior I painted over a little metal tubelike part that I have since been told may be the thermostat

Do I need to replace it now to control the amount of heat? I've only used the furnace to take the chill off before going to bed...not continuously overnight...

[Harry Young]

I need the model number or trailer model and year to be smart in any help I might offer...to my knowledge there is no wire, thermocouple, or mercury sensing tube "all these look alike" you can paint that would snooker the furnace...I can go thru with you from the most probable and most common problems based on model and description of the issue with a short series of questions and trys...I love this stuff so its no problem, some people like puzzles... I like long distance tech...

I'd like to piggyback on this thread....

I can get my furnace lit and have heat :-) But when painting the interior I painted over a little metal tubelike part that I have since been told may be the thermostat

Do I need to replace it now to control the amount of heat? I've only used the furnace to take the chill off before going to bed...not continuously overnight...

[Gina D.]

Christi, I have the same problem and I do as Harry suggests.

Sometimes it is almost impossible, even after I have it lit once, the next cycle it won't light in the 3 tries.

Frankly, I am about to rip the dang thing out. I like it when it runs, but trying to get it running is ridiculous.

A Wave 6 heater is in my future. No muss, no fuss, no bother, no electricity use.. and an increase in storage space ta boot!

[Orlen Wolf]

Check your 12V at the furnace with the fan off and with the fan running. I'll bet you will find enough of a voltage drop to slow the fan down a bit, right down to the "maybe I'll work and maybe I won't" point.

Even if you are on shore power you can have a voltage drop in the line especially if your egg has been around a while. A little corrosion at a wiring connection or a high resistance at a fuse cap will slow the fan down enough so the air prove will not activate. No air prove = no signal to the gas solenoid so you get no heat.

[Darwin Maring]

I had the problem with mine and found out there was water inside the furnace. Must have gotten in there during a rainstorm - through the air in exhaust out vents.

I removed the inspection plate inside the camper, removed the burner and soaked up the water with a rag and cleaned the burner and put it back together and it worked fine. Have had to do this twice through out the years.

Note, The gasket is fragile so have some high temp gasket material (Silicone in a tube) ready so you can get it back air tight.

[Gina D.]

Orlen, good thought, but voltage drop was my very first thought when it started happening regularly. I double and triple checked.. doesn't seem to be any rhyme or reason there. It sometimes hits at 12, and sometimes at 11.. or 13. I cleaned the connections and reseated all I could get to.

Nothing helps. I know better than to mess with propane and 'lectricty.. I know nothing of how these things safety precautions should be.

I want a non vented and passive cat heater anyway. I am a "low to no" current sucking freak. I was really happy with my wave 3 in my 13. It replaced a vented cat heater that had a fan.

Half the time now, as it is, I have to use my black cat heater because the furnace won't light.

I will note that one thing about my furnace that really scares me is it sometimes makes a huge explosion when trying to light.. like a backfire. Sounds like a gunshot when outside the rig, and it's a big "Whoosh" when inside. Like when your water heater fires up after lighting the pilot and it catches.

It DOES light after that boom, however.

[Alf S.]

Hi: All...Propane isn't on my "DYI" project list. I have seen the side of a slide in camper where the fridge ran amok and it was chared and melted!!! This stuff is volitile and worth seeking a well trained and qualified Tech. for service!!!
Alf S. North shore of Lake Erie

[Orlen Wolf]

Orlen, good thought, but voltage drop was my very first thought when it started happening regularly. I double and triple checked.. doesn't seem to be any rhyme or reason there. It sometimes hits at 12, and sometimes at 11.. or 13. I cleaned the connections and reseated all I could get to.

Nothing helps. I know better than to mess with propane and 'lectricty.. I know nothing of how these things safety precautions should be.

I want a non vented and passive cat heater anyway. I am a "low to no" current sucking freak. I was really happy with my wave 3 in my 13. It replaced a vented cat heater that had a fan.

Half the time now, as it is, I have to use my black cat heater because the furnace won't light.

I will note that one thing about my furnace that really scares me is it sometimes makes a huge explosion when trying to light.. like a backfire. Sounds like a gunshot when outside the rig, and it's a big "Whoosh" when inside. Like when your water heater fires up after lighting the pilot and it catches.

It DOES light after that boom, however.

Gina D.

I guess I didn't make it clear that I was responding to Christi V's original post with the comment on checking the 12V line.

I've seen problems with voltage sag on a 12V system when lights are turned on or if the refrigerator (especially the refrigerator with it's high current draw) is set to 12V operation. It often takes a while to isolate the problem since the dynamic load on the 12V bus could be, and very often is, different every time the furnace tries to light. I know of at least two people who have bought new furnaces when they had intermittent ignition problems and the problems persisted with the new units. Eventually we were able to trace the fault to varying 12V and found a specific component/splice/condition that caused the voltage variation.



One comment on your situation where you describe the "explosion when trying to light.. like a backfire". The only way that would happen is if your blower isn't clearing the firebox before the ignition cycle starts. I've seen this happen if there is a partial obstruction in the firebox outside air intake or exhaust vent. The most common obstruction is a wasp nest and when that is the problem the nest usually moves around so the problem is intermittent. At least if that is the problem the heat usually kills the wasps so you have a vacant wasp condo to remove. The job could get exciting if the wasps were still occupying the nest.

I also agree with your comments on messing with propane and electricity. If you don't have the training and experience then save up your bucks and take the problem to a pro.

Rule for working with electricity: Always ensure that the circuit is disconnected from the source of power lest ye be deposited on your buttocks in a most undignified manner.

Rule for working with propane: Propane + air + spark = disaster

[Gina D.]

'lectricity I have no issue with. I work with it all day for a living..

it's the nasty "spark" part near propane I am leary of

Thanks for the blockage info. I'll get the manual and see if this is something I should be looking at without violating safety things.