Issue with new Honeywell thermostat

FastEddieB · April 01, 2021, 06:22:08 PM

Been ages since I've visited this forum - sorry, but life gets in the way sometimes.

We just set up our 21BHS at a cousin's house to help take care of her. I decided it was time to upgrade the original thermostat with a digital one and settled on a Honeywell TH1100DV. Installation was simple, but first cold night - last night - it started out fine, cycling on and off to hold 70°F. But then it stopped doing so, allowing the temp to drop to 62° and never coming back on. Turning it off and then back on and we had heat, but twice more it did the same thing. Not good on a cold night. My theory is that if the furnace fails to light, which it sometimes does, the thermostat gives up and doesn't try again. The manual has various settings - I haven't messed with them, so they should still be at default settings. Has anyone else had this problem, and are there any settings I should mess with? Thanks.

Merlin · April 01, 2021, 09:24:24 PM

I just have 2 ideas.

First, make sure it's a good battery with good connections in the thermostat.

Second, double checking the wire connections in the thermostat going to the furnace.

If you can't easily and quickly figure it out, ditch the Honeywell and get a Lux Pro. Never had a problem with mine.

https://www.amazon.com/LuxPRO-PSD010BF-Heating-Digital-Thermostat/dp/B005FYNCJW/ref=sr_1_4?crid=2Q565LB506KZ7&dchild=1&keywords=luxpro+thermostat&qid=1617322685&sprefix=Luxpro%2Caps%2C197&sr=8-4

PDX David · April 02, 2021, 12:49:13 PM

Quote from: Merlin on April 01, 2021, 09:24:24 PM...ditch the Honeywell and get a Lux Pro. Never had a problem with mine.

I also upgraded to a LuxPro 2 (just on/off - no auto fan) and have been quite pleased. Simple to install. Earned five stars on last outing with temperatures in the 20's overnight it kept inside temp near setpoint of 55 all night. Learning my lithium battery could easily handle that power draw (about 30 amps) we bumped it up to 60 degrees on second night.

.......David

FastEddieB · April 10, 2021, 06:52:28 PM

Sorry for the delay responding.

Thanks for the input. The next night it worked pretty well, occasionally taking a couple tries to ignite the furnace.

Silly question: where does one go to find the burner for the furnace? If it's like the A/C and the water heater, it may just need cleaning - and looking for wasp nests!

Powder Hounds · April 10, 2021, 07:57:46 PM

I might be off topic but, I had issues with our furnace not igniting, the fan would run but no burner. Sometimes it worked, sometimes not? Thought it was the thermostat, it wasn't. There should be a black reset toggle switch inside the exterior access cover, try that to see if it will ignite a little better? Ultimately ours had a faulty limit switch. The furnace was replaced curtesy of LL. Works perfect now.

Merlin · April 10, 2021, 11:10:04 PM

Quote from: Powder Hounds on April 10, 2021, 07:57:46 PM
I might be off topic but, I had issues with our furnace not igniting, the fan would run but no burner. Sometimes it worked, sometimes not? Thought it was the thermostat, it wasn't. There should be a black reset toggle switch inside the exterior access cover, try that to see if it will ignite a little better? Ultimately ours had a faulty limit switch. The furnace was replaced curtesy of LL. Works perfect now.

The external furnace intake/exhaust is located on a black panel that's held on with 4 screws....probably #2 square drive. Remove that panel and you'll be into the furnace burner area. On the inside of the camper opposite the external part will be an access panel of Azdel. Remove that and you'll have access to the blower area for cleaning. It's a mess because LL apparently didn't own a vacuum cleaner.

I hope a complete inside/outside cleaning will help it run reliably. All of the RV furnace manufacturers have their owner's manual on-line. Some are snotty and don't post the full repair manual, but it's findable for them too.

LoneWolf04 · May 26, 2021, 10:40:45 AM

I installed a Honeywell th1100dv1000 (heat only) thermostat. Last week was the first week I used it while in the camper. Was getting down to 60 every night and left it at 65. Woke up every morning without issue. Even before the trip I let it run overnight in michigan when it was getting down in the 40s for a couple nights with no issues.

I will say that my heater turns on with the first ignition without hesitation though.