Issues with my furnace

[Nickmccartney]

I’m at my wits end with this thermostat/furnace. I can’t figure out why during the night tempature drops and the thermostat wont
kick the furnace on. Any one had a similar issue ??

notes
-once the tempature drops below deaired
temp the only way to get the furnace back on is to reset the thermostat
-propane is full
-turning temp up on the thermostat doesn’t turn the furnace on

it’s getting into the 30’s at night

[TucsonJim]

You can try to reboot the thermostat. Depress the large round knob for 12 seconds. When the knob is held for 4 seconds, the thermostat will go to the units selection screen, after another 4 seconds, the thermostat will begin a count down. Once the countdown reaches 0 and the display turns off, the device will wait for the knob to be released. Upon the release of the knob, the device reboots.

If this doesn't solve the problem, then further trouble-shooting is warranted. Do you have a volt meter to perform trouble-shooting with?

If you don't already have a copy, here's a link to your thermostat manual:
https://library.coleman-mach.com/wp-...2/1980R189.pdf

Jim

[Scott'n'Wendy]

Have you tried setting the tstat to heat only? Rather than cool and heat?
I don't have dual A/C, is that why you have two tstats?
If they are identical units, and they appear to be, try switching them. Perhaps the one that controls the furnace is having an issue.

[Nickmccartney]

Thank you guys for the great responses. @tusconjim I have tried that a bunch of times. No luck. I am happy it’s warranted however I’m in it full time with work. I spent all this money on a new grand design cause I heard good things about their warranties. I’m really hoping they will help but from what I understand most don’t want to pay service fees amd
auch. Seems like it might not be as good of a warrertiy as I was explained but I could be wrong. Not mad about it at alll just need to find a solution. Have a 10 month old I’m trying to keep warm and even at 60° it’s not good for her.

@scott’n’wendy I thought the exact same as you. Tried it. No difference.

[Nickmccartney]

@scott’n’wendy yes I also tried the heat only option. Have tried every option on the T stat available. No differences in any of them

[Nickmccartney]

howson
absolutely !!!! You guys are helpful. Not a newbie to full timing just a newbie to GD.


mine T stat is is model 9420-381

Symtoms we are having is it seems mostly at night the temp will drop from the desired set tempature and the furnace will no kick back on unless manually reset. Even once re set if it has to much to come back up it won’t go all the way back to desired. It may only go up about 5 degrees max and then it will turn back off and need to be manually reset again.

we have tried checking all 12v system. Batteries are good. Only thing that threw a little red flag to Rv repair guy is my converter is staying at 14.6v whigh they told me was in overload mode. Haven’t seen it come off of 14.6 personally. Tried changing out the motherboard, didn’t work. Check sails switch it’s good. Tried swapping the t stats. No difference

[howson]

@scott’n’wendy yes I also tried the heat only option. Have tried every option on the T stat available. No differences in any of them

FYI the (duplicate) question in the Thermostat Setting Doesn't Hold thread was deleted (duplicates are not allowed) -- let's keep the conversation in this thread, OK?

Based on what I've read in this thread, swapping the thermostats didn't solve the issue. Trying all the different modes on the thermostat didn't make a difference, either. Finally, the furnace does not even attempt to light at night (fan doesn't start up). Are those statements accurate?

For the moment I'm going to assume the thermostat is not the issue. If that's the case, the other possibilities are propane, DC voltage, and/or the control board on the furnace. If you'll address the following questions it will help guide further inputs:

1) Is the reason the problem is only experienced at night due to the trailer being unoccupied during the day? Or does the furnace work fine, cycling on and off during the day then fail only in the evening?

2) Does your rig have solar?

3) Do you have a multimeter and know how to use it?

4) What specific year/model of GDRV? Can you definitively identify the make and model of the furnace? (Please fill out your signature line as requested in the Welcome Letter -- thanks!)

Howard

[howson]

Nickmccartney -- moved your (newest) post to this thread, too. Due to the timing it is post 6 in this thread. For readers, his post is in response to a question about the model of thermostat.

[Nickmccartney]

howson

1- I trailer is occupied during the day, I would say it’s “better” during the day but still not right. We notice that it cycles by itself closer to normal during daylight hours. It seems every night it has issues will drop way down if we don’t reset the T stats.

2- it does have solar panels and inverter. I have 100% no idea how to use them. New to GD and the 15 walk through wasn’t quite enough time for me to learn it which is my fault not theirs. - more to this. Before we hooked to shore power I noticed the batteries were dying, almost as if the panels weren’t working. Don’t know if that’s all linked but it got to the point where even my led lights wouldn’t come on before hooking to power

3- I do have one and can use it.

4- I have a 2024 GD solitude 387MBK
the furnace is suburban- don’t know the model number

[howson]

howson
absolutely !!!! You guys are helpful. Not a newbie to full timing just a newbie to GD.


mine T stat is is model 9420-381

Symtoms we are having is it seems mostly at night the temp will drop from the desired set tempature and the furnace will no kick back on unless manually reset. Even once re set if it has to much to come back up it won’t go all the way back to desired. It may only go up about 5 degrees max and then it will turn back off and need to be manually reset again.

we have tried checking all 12v system. Batteries are good. Only thing that threw a little red flag to Rv repair guy is my converter is staying at 14.6v whigh they told me was in overload mode. Haven’t seen it come off of 14.6 personally. Tried changing out the motherboard, didn’t work. Check sails switch it’s good. Tried swapping the t stats. No difference

The next item I'd check is the two-stage pressure regulator under load, meaning with the furnace lit. The value should NOT drop below 11" of water column (WC) under load. When propane is abruptly turned off, the "lock off" pressure cannot exceed 14" WC. This is something you'll likely need an qualified RV technician to check (having the proper tools and training is not common).

Alternatively, buy a replacement two-stage valve at any RV store (NOT a "big box" hardware store--might be the wrong type!) and swap it in. Might be a lot less expensive than paying an RV technician if swapping is in your skill set.



Why the regulator? What could be happening is that during the day when it's warmer there's just enough pressure to keep the furnace running. At night, especially when it's colder, there's not enough pressure to keep the furnace lit. The furnace tries three times to relight and fails, so it goes into lockout. The only way to get it to start back up is to reset the furnace (exactly the scenario we're dealing with here). In the interim between lock out and reset, there's enough pressure back in the system to relight the furnace, but then pressure subsequently drops and the cycle repeats.

Just an educated guess on my part, but where I'd investigate in your shoes.

Howard

[howson]

Nickmccartney -- added the Solitude to your forum sig line for you.

[Nickmccartney]

howson

okay. I can check this which could make sense especially because the first time I noticed this happening was when I changed over to my 100# bottle. Only questions is that all my other LP appliances work great, on demand water heater is good. Stove good oven good. What’s your opinion about that?

[howson]

Nickmccartney

In your Solitude, the Furnace system has a high draw up to 34,228 BTUs, In contrast, the water heater is 11,742. If you have an "RV" refrigerator, 3,081 BTUs. The stove and oven (if everything is lit) could draw up to 42,500 BTUs, but they are not monitored like the furnace nor if there's a drop in pressure with they go into "lock out" like the furnace.

The symptoms (IMO) point to a propane-related issue. I definitely could be wrong -- but if it quacks like a duck and walks like a duck...my first assumption is it's a duck (until proven wrong).

Howard

[Nickmccartney]

howson can you explain the 11” WC and 14”WC another way to me that maybe I can understand ?

[howson]

howson can you explain the 11” WC and 14”WC another way to me that maybe I can understand ?

Water column is a pressure value (very low) measured by a device called a manometer. If the two-stage regulator is not working correctly by maintaining the correct WC (not uncommon) the furnace typically doesn't work right.

For specifics on "WC", there's a plethora of material on the internet. A few after a quick search:

https://www.nficertified.org/wp-cont...Jim-Brewer.pdf

https://blog.goodsam.com/what-do-you...-water-column/

https://hvacrschool.com/in_wc/

Howard