Bad Thermostats

Geo9350 · 09-30-2015, 08:07 PM

Hi, I'm back again, this time I am having problems with my thermostats. I have the 8530-348 RV Comfort-HP in the living room and it works sometimes with the furnace but at night will stop working and it gets cold but if I put it on heat pump it keeps the RV warm all night. Also it is off in degrees, I have to click it up or down till the ac comes on then when it gets to the temp I want I have to click it till it turns it off and it reads several degrees off from true room temp. The one in the bedroom just operates the AC and the digital reading is messed up so I can't tell what it is set at, but partial numbers show so it looks to be off in temp also. I heard there is are better thermostats I can replace these with instead of buying the same piece of junk. Has anyone the information on what I need to buy? Thanks.

RCAircraft · 10-02-2015, 09:26 PM

Wow-that's a bunch of problems. If my RW, I would get the electrical diagrams, from this site or others and check voltages at the thermostats as the first step. There could be loose connections so also check wire terminals and any wire nuts at the thermostats and AC's on the roof.

atom ant · 10-02-2015, 10:18 PM

I'm interested to hear if you can replace with a more modern as well. Mine isn't very accurate either, in fact we use it more manually than anything.

I am years past having any experience on thermostats, but I believe the obstacle was always accommodating the 2 speed fan. It used to be you could add a switch on the new style thermostat, but I don't know anymore.

Attached below is the manual if you want to see it. Wiring looks reasonably standard

RCAircraft · 10-03-2015, 02:17 AM

Quote:

Originally Posted by atom ant

I'm interested to hear if you can replace with a more modern as well. Mine isn't very accurate either, in fact we use it more manually than anything.

I am years past having any experience on thermostats, but I believe the obstacle was always accommodating the 2 speed fan. It used to be you could add a switch on the new style thermostat, but I don't know anymore.

Attached below is the manual if you want to see it. Wiring looks reasonably standard

There are other T'Stat solutions out there. My thoughts - our RW's main stat was inaccurate in the beginning. As the sensor is onboard with the stat I noticed that the mounting service was warm to touch. The circuit breaker panel and converter are mounted near the floor however there is a cavity in the wall allowing the heat from the panel to travel up to the stat. Removing the stat from the wall, plugging the hole behind the stat with insulation and placing an insulating material between the stat and and wall should super improve the stat's accuracy for you. Any stat, with an onboard temp sensor most likely wifi not perform much better than the RW stat. From my previous control engineering days I believe that the stat supplied with our RW is a very good product for the application.

atom ant · 10-03-2015, 05:17 PM

Quote:

Originally Posted by RCAircraft

From my previous control engineering days I believe that the stat supplied with our RW is a very good product for the application.

But its not cute - like Dometic

Redwood2013 · 10-03-2015, 07:27 PM

I had a light switch just below the thermostat that put off a lot of heat. That caused the thermostat to miss read the actual temperature.

There are 2 banks of light switches below thermostat. I flip flopped these switches and the heat problem went away.

My "guess" after competed the flip flop was some wires were not secured properly which created resistance i.e. Heat.

Hope this helps

atom ant · 10-03-2015, 07:45 PM

did that go smoothly? No holes or anything to cover?

Redwood2013 · 10-03-2015, 08:17 PM

Had to mark every wire and it's location. Used painters tape to write on, then attach to each wire. This took some time.

Unplugged the wires from both banks of light switches (light switches were the same size, so were the hole in the wall). No extra holes to drill or hole in wall to cover up.

I spent about an hour making the change.

Personally like the change, now the bottom bank of switches control downstairs lights, top bank controls upstairs and outside lights.

atom ant · 10-03-2015, 08:33 PM

I'll add it to my to-do list! thanks!

NW Snowbirds · 10-03-2015, 09:07 PM

I have a single bank of three switches directly below the thermostat. I can feel the warmth in the switch plate especially when all three switches are on. I have learned to increase the thermostat setting when heating by about three degrees to hold the desired temp in the room.

Redwood2013 · 10-03-2015, 09:18 PM

As a side note, I did purchase a new thermostat. Still had the same miss read issue. Used a laser temp gun and found the wall above light switch (just below the thermostat) was 8 degrees warmer.

Between the 2 banks of light switches was cooler, therefore I flip flopped the switches.

Geo9350 · 09-20-2017, 08:07 AM

Ok, I replace the thermostat with the same model (new). I cut a piece of insulation sheet to put between the thermostat and the wall. That helped the temperature reading to be more accurate. I still am having problems with the furnace part. Actually I have two problems with the furnace. I put on gas heat and the furnace lights off. Then sometime during the night the temp drops and the furnace doesn't light off. So I get up and turn the thermostat to off then back on to heat and the fan starts up. Sometimes it lights, sometimes it doesn't. I have had to turn the thermostat off and on several times before the furnace will light off. I have ordered a new ignitor and soon as it gets here Thurs I will replace that, but it may be the control board, who knows, but why isn't the thermostat turning on the furnace when the temp drops, I have to turn off and back on to get it to start the furnace. I kind of wonder if it tries and since the furnace doesn't light it shuts back down and you have to turn off and back on to reset the furnace to try to light again. Not sure, but it has done this when I'm awake, it would get cold and I would walk over to the thermostat and turn off and on and the furnace would kick on to try and start. Has anyone else had this problem? Are the new Redwoods coming out with this same type thermostat or did they put something better in the new models?

**hoosierguy** · 09-20-2017, 03:30 PM

It is my understanding that the furnace thermostat and control system attempts to start the furnace 2 or 3 times. If the furnace burner does not ignite, the system will shut down until you turn off the thermostat which resets the system. Then it will go through the same ignition process again.

I suspect you are on the right track that the problem is in the igniter or furnace control board. Also, when the thermostat calls for heat, the air circulation fan is supposed to start up and run for a few seconds causing a "sail switch" to be set which then allows the ignition process to start.

Hope this helps.

Geo9350 · 09-23-2017, 07:44 AM

I pulled the furnace out of the RV. That in itself turned out to be an adventure. I had to pull the wall down inside the boot to get to the back side of the furnace. I removed the back panel with the three vent hoses attached by removing 2 screws, one top one bottom and pushed aside then removed the top two vent hoses by twisting them out of the frame (they have bayonet type connections). I looked thru the rear of the furnace and could see where there were screws holding the internal guts of the furnace to the frame. There was screws in both sides and bottom. It looked like the screws on the top was already gone. So I wound up having to pull the whole furnace out the side of the RV to access the one side and bottom screws that held the guts in. To remove the whole furnace after disconnecting the vent hoses and control and power wires there is 3 screws accessible from the outside the RV after removing the outer plate. Two on top and one on the bottom of the frame. Once I took out the guts from the frame I took it inside the house and watched Youtube on how to test it. I tied the two blue wires together that would be from the thermostat, 12v DC to the Red lead and ground to the Yellow lead. The fan started up and ran for a bit then shut down. Looking thru the little window I could see no spark. I then hooked up a meter and set for mill-amps using one lead of the meter to the disconnected wire from the igniter and other lead to the contact where I removed the wire from igniter on the control board. Ran the power again and there was no current when it was suppose to kick in so figured something was wrong with the control board. Taking out the igniter turned out to be an adventure, I had to take the top part of the housing apart for the motor and top part of the cover for the fan blade so I could get a wrench on the gas fitting for the pipe that runs between the valve and the furnace box. Since the squirrel cage was plastic and so many have complained of it designating, I ordered a new metal squirrel cage, control board made by Dinosaur, gaskets and new igniter just to make sure from Amazon. When the parts get in Monday I will install them and update the results.

RCAircraft · 09-23-2017, 05:10 PM

Quote:

Originally Posted by Geo9350

I pulled the furnace out of the RV. That in itself turned out to be an adventure. I had to pull the wall down inside the boot to get to the back side of the furnace. I removed the back panel with the three vent hoses attached by removing 2 screws, one top one bottom and pushed aside then removed the top two vent hoses by twisting them out of the frame (they have bayonet type connections). I looked thru the rear of the furnace and could see where there were screws holding the internal guts of the furnace to the frame. There was screws in both sides and bottom. It looked like the screws on the top was already gone. So I wound up having to pull the whole furnace out the side of the RV to access the one side and bottom screws that held the guts in. To remove the whole furnace after disconnecting the vent hoses and control and power wires there is 3 screws accessible from the outside the RV after removing the outer plate. Two on top and one on the bottom of the frame. Once I took out the guts from the frame I took it inside the house and watched Youtube on how to test it. I tied the two blue wires together that would be from the thermostat, 12v DC to the Red lead and ground to the Yellow lead. The fan started up and ran for a bit then shut down. Looking thru the little window I could see no spark. I then hooked up a meter and set for mill-amps using one lead of the meter to the disconnected wire from the igniter and other lead to the contact where I removed the wire from igniter on the control board. Ran the power again and there was no current when it was suppose to kick in so figured something was wrong with the control board. Taking out the igniter turned out to be an adventure, I had to take the top part of the housing apart for the motor and top part of the cover for the fan blade so I could get a wrench on the gas fitting for the pipe that runs between the valve and the furnace box. Since the squirrel cage was plastic and so many have complained of it designating, I ordered a new metal squirrel cage, control board made by Dinosaur, gaskets and new igniter just to make sure from Amazon. When the parts get in Monday I will install them and update the results.

That is super great recap of your digging in. About two years ago my furnace had a similar failure. My GS extended warranty took care of the cost else I would have talen the same route. After taking out the wall the first observation was that several flexible ducts were off the furnace. Lots of aluminum heat duct tape was used in securing the ducts to the furnace. While out I had all the internal and external connections checked then the assembly thoroughly cleaned. When bypassing the water pump for winterizing I put an eye ball on the furnace duct connections.

Geo9350 · 09-26-2017, 05:19 AM

I received the parts today, I put the new control board in and igniter and put the furnace back together and put in the RV. It wouldn't light so I pulled it back out and took back in the house. While messing with it the motor took off faster and things worked right but then next time I tried the motor just ran slower than suppose to. So I think I figured it out to be the motor working intermittently running normal speed and things work and not running fast enough. I will have to go out and find a metric allen wrench that will fit the screw on the plastic fan blade so I can remove it and put on the new metal one when I get the new motor. Geezz, I will have replaced almost every part in this stupid thing by the time I get done. I guess it might have cost less if I had taken it to an RV repair, but the closest one to me is at least 150 miles. I'll let you know how things go when the new motor gets here Wed.

Geo9350 · 10-04-2017, 01:28 AM

I got the new motor, no change, still wouldn't light. I sent the control board back to Amazon and ordered another one. Put it in and it won't spark. I called the company Dinosaur and he had me ship it to him to see what is wrong with the control boards I am getting. So shipped it out today, will see what happens next. Kind of put a wrinkle in my plans, was gonna pull the RV up to Duck Creek Village Ut today, but that isn't happening. I wish there was a furnace I could buy to replace this piece of junk that has a pilot light. I hate these electronic starts, they fail too much. If anyone has replaced their furnace with one with a pilot light, please let me know.

**hoosierguy** · 10-04-2017, 02:34 AM

Quote:

Originally Posted by Geo9350

I got the new motor, no change, still wouldn't light. I sent the control board back to Amazon and ordered another one. Put it in and it won't spark. I called the company Dinosaur and he had me ship it to him to see what is wrong with the control boards I am getting. So shipped it out today, will see what happens next. Kind of put a wrinkle in my plans, was gonna pull the RV up to Duck Creek Village Ut today, but that isn't happening. I wish there was a furnace I could buy to replace this piece of junk that has a pilot light. I hate these electronic starts, they fail too much. If anyone has replaced their furnace with one with a pilot light, please let me know.

This link might give you some insight to troubleshooting the furnace issue.

Troubleshooting RV Furnace Problems

Hope this helps.

r time soon · 10-04-2017, 02:40 AM

Make sure your battery condition and voltage is good. If batteries are weak, the fan won't spin fast enough to move the sail switch. If the sail switch doesn't engage then it won't ignite.

Chris

2012 36RL

**hoosierguy** · 10-04-2017, 02:49 AM

Some additional sources of information.

Service Documents and Manuals

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