Help - Furnace won't ignite

[Mels Musty Music]

Just returned from a trip to Minnesota from Washington stste. Experienced temps from the 50's to the 90's. A/C and furnace ran perfectly when needed. After we got home I wired an interior swith for my water heater as described in various posts on the forum. Water heater works fine but my furnace won't ignite anymore. When I turn it on ( with the temp setting 10 dergees higher than current temp ) the blower comes on fine and after the proper delay the igniter clicks but the burner doesn't fire. On the third and final try of the igniter it sounds like the burner has fired but there is no heat comimg from the exhaust or registers. After the proper delay the blower shuts off.
I'm still under warranty but plan on leaving again soon and dealer can't get me scheduled in time. Figured I must have caused the problem so should be able to fix it.
One of my tanks was empty so thought that might be a problem but refilled it today with same results. Stove and refrigerator are working fine.
Will appreciate any help someone can offer.

[lightningjack11]

Just a thought. Make sure all water heater and fridge work properly on gas to insure gas is getting to your furnace. Try a higher thermostat setting. The installed themostats are not too good. I have always had a problem with mine.

[Montana_621]

Where is Minnesota were you? I live in MN and am curious. I haven't seen that anyone on the forum has been thru here.

quote:Originally posted by Mels Musty Music

Just returned from a trip to Minnesota from Washington stste. Experienced temps from the 50's to the 90's. A/C and furnace ran perfectly when needed. After we got home I wired an interior swith for my water heater as described in various posts on the forum. Water heater works fine but my furnace won't ignite anymore. When I turn it on ( with the temp setting 10 dergees higher than current temp ) the blower comes on fine and after the proper delay the igniter clicks but the burner doesn't fire. On the third and final try of the igniter it sounds like the burner has fired but there is no heat comimg from the exhaust or registers. After the proper delay the blower shuts off.
I'm still under warranty but plan on leaving again soon and dealer can't get me scheduled in time. Figured I must have caused the problem so should be able to fix it.
One of my tanks was empty so thought that might be a problem but refilled it today with same results. Stove and refrigerator are working fine.
Will appreciate any help someone can offer.

[Mels Musty Music]

Melissa -

Spent one week in North St. Paul and one week in Cloquet so my wife could attend her Duluth Denfeld 45th reunion. I am originally from South St. Paul. Spent the 70's in Esko and moved to Washingtom in 1980.
Thats probably more than you wanted to know. Where do you and Mike live?

Hank

[Montana_621]

LOL! Oh, never too much info! I work in St. Paul, in the midway and at the moment Mike is out of a job. We live on the WI / MN border so I know exactly where North St. Paul and South St. Paul are. Did you grow up by the stock yards? The North St. Paul Polars... that's cool! Don't they have a huge snowman along hwy 36 down there?

[RVWheels]

MMM,
Sounds like it might be your igniter board. I think many of us have had a problem with that. Since you're still under warranty just get it back in for a service check. They can tell real quick what the problem is. Good luck.

RVWheels

[Montana_782]

We had the same problem with our brand new 3670. We took it to an rv repair shop wnd they removed the furnace,bench tested it (worked fine) then re-installed it...The only comment was that the factory uses a quick connect system on the wiring and it sometimes doesn"t work. They solder joined the connections and all seemed fine.BUT>>> we encountered the same problem again after the propane ran dry. We were using only one tank at a time with the second tank shut off. This creates some kind of problem(air lock???) since the propane tanks were designed to work with both tanks on. The cure was to go out to the port sied tank where the changeover switch os located and manually switch the tanks back and forth till it clears itself ( Usually several tries) ( the reason for us using one tank at a time was to insure we would not accidentally run out if fuel...now we've installed a warning light inside the trailer to let us know and we keep both tanks turned on ) hope this helps gf

[Mels Musty Music]

I too assumed it was the igniter board and proceeded to pull the furnace out and took it in to be bench checked at the dealer we purchased the trailer from. Was easeir to take it out myself than pull the trailer through the traffic on the Narrows bridge going into Tacoma. Besides we had just cleaned it inside and out in preperation for our next trip this fall to the east coast.
Anyway I won't find out until next week what they find and after reading about gforbes's experience I'm thinking it might check out OK too. The reason I think that is because when I removed the empty tank there was backpressure on the line. Never entered my mind that it could be an airlock but thats sure what it seems like now. I usually open both valves when setting up but I probably skipped the empty one somewhere along the line.
Thanks for the advice and will let you know what the outcome is.
Hank

[Random Line]

[quote]Originally posted by Mels Musty Music

I too assumed it was the igniter board and proceeded to pull the
----------------------------------

I'm sure the dealers all know this but I didn't until I was told what our similar problem was. If there is less than 10 and 1/2 volts reaching the furnace it won't ignite. In our case we had a weak battery and were boondocking at 10 degrees F. A quick batery charge made the difference. And we were toasty again. Did you loosen the connections to the furnace as you put that switch in? Check the voltage just ahead of the furnace and see what is getting through.

Good luck.

[Mels Musty Music]

I see there are a couple more topics posted recently that seem very similiar to my problem. Guess I need to be more explicit in my descriptions..
Anyway after removing furnace and taking it in to the dealer I got the dreaded call back that it checked out perfectly on the bench. Picked it up and re-installed today and still won't ignite. I should say that occasionally it sounds like it ignites but it won't stay lit for more than 2 seconds. Opened the gas lines and everything seems to be clear. Water heater, range and refrigerator are all working fine on gas.
Guess I call the dealer tomorrow and take the trailer in this time. Only problem is we leave in a week from friday for New England. Guess I'll see how good their service is.
Will let you know what happenes next.
Hank

[OntMont]

This type of furnace problem seems to be a recurring theme of this forum. I have posted this information several times before, but here it is again.

A friend we met on the road (also from MN), and ourselves have both had a furnace problem that after extensive (and expensive) checking of the furnace, turned out to be caused by a lack of gas pressure. The cause is that the flow-limiting safey valves in the propane tank pig tail on the far side from the regulator will close because of the high gas flow required to fill the cross over pipe that runs from side to side. (The sudden high flow looks like a leak to the flow limiting valves, so they close.) This situation can be prevented by opening the tank valve very slowly. Once it has happened, a quick cure and check is to switch the tanks from side to side. Marshall gas regulator company recommend the instalation of an additional intermediate regulator on the far side tank as the proper permanent solution. It is also important to understand that this problem is only apparent with the furnace because of its high demand for gas, other appliances will likely continue to work because the valves are flow limiting, not shut-off valves. I belive that the furnace has a built in low gas pressure cut-out that shuts the furnace down on low gas pressure.

If you call Marshall Gas Regulator Company, they can provide the full technical explanation as well as the suggested additional regulator.

[sreigle]

Mel, I sure wish I'd realized you folks are in the St. Paul area. We spent the nights of 7/25-26 in Apple Valley on the Minneapolis side so Vicki could drag me to the MOA. Sorry we missed out on meeting you folks.

[Mels Musty Music]

First let me thank all of you who responded with possible fixes for the problem I was having with our furnace. I tried everyones suggestions numerous times but nothing seemed to work. Finally called my dealer who couldn't get me in until the day before we left on our next trip. Not acceptable as we couldn't afford to take a chance how long they would take to fix it. Called A-1 RV in Silverdale and after listening to my story they said bring it in that afternoon as they thought they could get me in and out that day. Can you believe there are RV repair places that can respond that quickly? Anyway I took the trailer in and my problem turned out to be a kinked gas line on the regulator side. They said it probably came from the factory that way and really couldn't say why the furnace had sufficient gas pressure to operate properly on our trip to Minnesota and at this point I really don't care - as long as its fixed. I consider myself somewhat of a do-it-your-selfer and can't figure out why I didn't discover what the problem was after all the time I spent checking things out.

Thanks again for everyones help. This is an excellent forum and it seems like I learn something new almost every day.

Steve & Vicki - When you were in Apple Valley we were in North St. Paul so we weren't too far apart. Heading back in that direction in a week but will be going farther north - thru Winnipeg this time. Hope our paths will cross someday.
Hank

If anyone ever needs parts or service while in Western Washington check out A-1 RV in Silverdale. You won't be disappointed.

[sreigle]

I try to post where we'll be in the forum titled something like 'who, what, where' so if you see we'll be close, give us a holler. We've met a dozen or so members that way so far, every one just as nice as you'd expect Montana owners to be. Hope to see you on the road some day. Sorry we missed everyone this time around.