Furnace/Thermostat Issue

[Dlambert]

Hi,

I have a 2024 Grand Design XLS 23LDE with the basic single zone Furrion thermostat, Suburban furnace and Furrion 15k ac unit. The thermostat is the newer model with the heat sensor on the bottom.

I have a problem and a question:

When set to “Heat”, the furnace starts and supplies heat. It reaches the set temp, and shuts down normally. However, as the inside temp drops below the set temp by as much as 10 degrees, the furnace never restarts. I have to power off then power on the thermostat to restart the furnace. Sometimes just cycling through the “Modes” back to Heat will restart. How can I determine if this is a thermostat issue or a furnace issue?

Separate question, I have a “High” and “Low” (and “Auto”) fan setting on the thermostat. Should I hear a difference in the speed of the AC fan? Both settings seem to make the same noise and move about the same amount of air.

Thanks,

William

 

[RV2600RB]

I have the opposite problem. Furrion thermostat set at 60 and doesn’t shut off till 68.
Going to try a Micro Air thermostat.
Rich

 

[Papaz8]

Furnace fan?

Hello, I have a separate but related question. When the furnace is on, and the fan set to whatever, why do the roof a/c ducts blow air and not the floor furnace ducts? Makes no sense to me. Is there not a separate fan for the furnace?

Cheers!
Papaz8

 

[RV2600RB]

Hi,

I have a 2024 Grand Design XLS 23LDE with the basic single zone Furrion thermostat, Suburban furnace and Furrion 15k ac unit. The thermostat is the newer model with the heat sensor on the bottom.

I have a problem and a question:

When set to “Heat”, the furnace starts and supplies heat. It reaches the set temp, and shuts down normally. However, as the inside temp drops below the set temp by as much as 10 degrees, the furnace never restarts. I have to power off then power on the thermostat to restart the furnace. Sometimes just cycling through the “Modes” back to Heat will restart. How can I determine if this is a thermostat issue or a furnace issue?

Separate question, I have a “High” and “Low” (and “Auto”) fan setting on the thermostat. Should I hear a difference in the speed of the AC fan? Both settings seem to make the same noise and move about the same amount of air.

Thanks,

William

Is the heat on “auto”?
Have you tried waiting to see if the heat will come on by itself? It may be more than 10*.
Yes, there should be a difference in airflow between low and high. There is in ours.
Rich

 

[RV2600RB]

Hello, I have a separate but related question. When the furnace is on, and the fan set to whatever, why do the roof a/c ducts blow air and not the floor furnace ducts? Makes no sense to me. Is there not a separate fan for the furnace?

Cheers!
Papaz8

If it’s on auto, air should only come out of the heater vents.
A bit more specific info would help. What setting exactly is the heat set to?
Rich

 

[Papaz8]

If it’s on auto, air should only come out of the heater vents.
A bit more specific info would help. What setting exactly is the heat set to?
Rich

Rich, I’ve only needed to use furnace twice and I’ve played with the fan settings each time. Air blows out of the a/c ducts and barely out of the floor heat vents.

 

[RockyRoad]

Hello, I have a separate but related question. When the furnace is on, and the fan set to whatever, why do the roof a/c ducts blow air and not the floor furnace ducts? Makes no sense to me. Is there not a separate fan for the furnace?

Cheers!
Papaz8

if you have the thermostat displaying the fan setting it will blow out the AC ducts. To run the furnace the thermostat needs to be displaying the furnace or heat setting. To change the fan setting for the furnace you need to go to the fan display then select low, high or auto. Then change back to the the furnace setting and wait a minute and it should kick on if the temp is low enough. It will blow out by the floor vents and they are 2 separate fans.

 

[RockyRoad]

Hi,

I have a 2024 Grand Design XLS 23LDE with the basic single zone Furrion thermostat, Suburban furnace and Furrion 15k ac unit. The thermostat is the newer model with the heat sensor on the bottom.

I have a problem and a question:

When set to “Heat”, the furnace starts and supplies heat. It reaches the set temp, and shuts down normally. However, as the inside temp drops below the set temp by as much as 10 degrees, the furnace never restarts. I have to power off then power on the thermostat to restart the furnace. Sometimes just cycling through the “Modes” back to Heat will restart. How can I determine if this is a thermostat issue or a furnace issue?

Separate question, I have a “High” and “Low” (and “Auto”) fan setting on the thermostat. Should I hear a difference in the speed of the AC fan? Both settings seem to make the same noise and move about the same amount of air.

Thanks,

William

Our system behaved exactly as you described, particularly when it was cold outside. We have the suburban furnace as well. We played with it for a long time, took it to the dealer and they said it was working ok.

Here's what we've done and it has helped a lot. Common sense stuff really but took us a while.

- make sure nothing is blocking the vents
- make sure nothing (trashcan) is blocking the power center/converter
- try setting the fan to low mode
- set the furnace to a realistic temperature for the outside conditions, like 67 if it's 40 outside. We were setting it to high, like 71 when it was 25 out (wife likes it warm). I believe this caused the furnace to trip due to overheating and once powered off then on at the thermostat it would run again because that reset the fault. The air coming out was VERY hot.

Just got back from a trip a couple days ago at moderate temps and the furnace worked fine. If we go up to the mountains again in September we can see how it does in colder temps. I'll probably shoot for 60 - 65 on the thermostat and us an extra blanket.

Also, there's a noticeable difference between low and high speed but it's not a huge difference in our 22MLE

 

[Papaz8]

if you have the thermostat displaying the fan setting it will blow out the AC ducts. To run the furnace the thermostat needs to be displaying the furnace or heat setting. To change the fan setting for the furnace you need to go to the fan display then select low, high or auto. Then change back to the the furnace setting and wait a minute and it should kick on if the temp is low enough. It will blow out by the floor vents and they are 2 separate fans.

Ahhh, thank you! I’ll play with it that way. Too warm to use it now, but wanted to get prepared as we will be spending our winter near Omaha.
Cheers,
Papaz8

 

[Dlambert]

Is the heat on “auto”?
Have you tried waiting to see if the heat will come on by itself? It may be more than 10*.
Yes, there should be a difference in airflow between low and high. There is in ours.
Rich

Rich,

I’ve tried it with fan in Auto, Hi and Off. same result.

 

[Dlambert]

i have an update, sorta.

I contacted GD, and after sending photos and S/Ns, they sent me a new controller board. This is the unit inside the indoor part of the AC. I replaced it, the AC works about the same, but couldn’t really test the furnace (90+ degrees in TN)

We finally got cool enough to run the furnace this morning and..no heat. The furnace blower starts, but no heat. It shuts off after 3-4 minutes and locks out. Cycled it a few times, no joy. I don’t think there’s an issue with the propane as we have been using the stove and the exterior outlet for the griddle. Guess I’ll be on the horn with Suburban.

I noticed the wall thermostat was reading very close to my digital thermometer when unit was turned Off and on Cool, but reads about 7 degrees warmer when in Heat mode.

 

[Dlambert]

Well, furnace is working again. I pulled it out and started checking the wiring. One of the brown wires for the gas valve on the underside had come loose…

Crimped the connector a bit tighter and it fired up normally. I used a battery and extra propane tank to set up a test bed. Let it run a bit, no issues.

Reinstalled and works normally in the camper. Now I need to get some cooler temps to see if it still fails to restart.

 

[GoGood]

if you have the thermostat displaying the fan setting it will blow out the AC ducts. To run the furnace the thermostat needs to be displaying the furnace or heat setting. To change the fan setting for the furnace you need to go to the fan display then select low, high or auto. Then change back to the the furnace setting and wait a minute and it should kick on if the temp is low enough. It will blow out by the floor vents and they are 2 separate fans.

I have the same problem in a 17 MKE. Selecting A,L,H are all the same high fan speed.

 

[Bruno Camper]

Hi,

I have a 2024 Grand Design XLS 23LDE with the basic single zone Furrion thermostat, Suburban furnace and Furrion 15k ac unit. The thermostat is the newer model with the heat sensor on the bottom.

I have a problem and a question:

When set to “Heat”, the furnace starts and supplies heat. It reaches the set temp, and shuts down normally. However, as the inside temp drops below the set temp by as much as 10 degrees, the furnace never restarts. I have to power off then power on the thermostat to restart the furnace. Sometimes just cycling through the “Modes” back to Heat will restart. How can I determine if this is a thermostat issue or a furnace issue?

Separate question, I have a “High” and “Low” (and “Auto”) fan setting on the thermostat. Should I hear a difference in the speed of the AC fan? Both settings seem to make the same noise and move about the same amount of air.

Thanks,

William

Regarding the heat not coming on after a cycle. I had the same problem. I disconnected the battery and reconnected it problem solved.
Kind of like powering off a Computer and restarting it.