Bedroom AC thermostat issue

[RickV]

My bedroom AC Thermostat is off by around 6-7 degrees. I have checked to make sure that the little red thermostat is in the right place. Is there anyway to calibrate/adjust it? Is it something I can replace? First two pictures show Bedroom onscreen and with portable thermostat near it Third and Fourth show living room. Portable Thermostat was placed next to the sensors.

[chuckster57]

I’m not sure what margin of error is allowed for the thermistors, but I’m sure you could replace it if you think it’s too far off.

[JRTJH]

Your In Command system uses remote temperature sensors located throughout the trailer to send "temperature information" to the HVAC system controller. There are several remote temperature sensors in your trailer. Based on your post, I'd guess that the actual sensor, located behind the plastic grill, is either buried too far inside the wall or is touching the wall and "sending false information".

If you remove the plastic grill protector, you can see the sensor located on the very tip of that wire bundle. Adjust it so that it's located in the center of the cavity formed by the grill and see if it improves the performance.

While it's possible that you have a defective sensor, I'd suspect that the connections are OK because there is "active control at the In Command unit. So, the wiring is probably OK and it's just the positioning of the sensor behind the grill.

Here's a photo of the Dometic assembly, the sensor is the small "dot" at the end of the wire and it's located behind the larger plastic grill. You may have a different brand, and it may look a bit different, but the function is similar.

[M&M2]

I had similar problem early on. I removed the sensor and insulated behind it so it measured the room and not the space behind it. Where one had no way to reach behind it I filled the hole with a bit of insulation.

[RickV]

Originally Posted by JRTJH

Your In Command system uses remote temperature sensors located throughout the trailer to send "temperature information" to the HVAC system controller. There are several remote temperature sensors in your trailer. Based on your post, I'd guess that the actual sensor, located behind the plastic grill, is either buried too far inside the wall or is touching the wall and "sending false information".

If you remove the plastic grill protector, you can see the sensor located on the very tip of that wire bundle. Adjust it so that it's located in the center of the cavity formed by the grill and see if it improves the performance.

While it's possible that you have a defective sensor, I'd suspect that the connections are OK because there is "active control at the In Command unit. So, the wiring is probably OK and it's just the positioning of the sensor behind the grill.

Here's a photo of the Dometic assembly, the sensor is the small "dot" at the end of the wire and it's located behind the larger plastic grill. You may have a different brand, and it may look a bit different, but the function is similar.

I did that a while back and it was like you described it should be.

Originally Posted by M&M2

I had similar problem early on. I removed the sensor and insulated behind it so it measured the room and not the space behind it. Where one had no way to reach behind it I filled the hole with a bit of insulation.

I will try this later on today and see if it helps.

[JRTJH]

Originally Posted by RickV

I did that a while back and it was like you described it should be. ....

You may have cool air or warm air coming up behind the sensor in the wall cavity. Insulating it so it isn't exposed to anything except the room air will probably fix your problem.

[ChuckS]

Two things can cause the temp variance you are seeing with your In Command HVAC in that zone..

One is the placement of the remote temp sensor..which you have already checked and state it is mounted outside of the wall itself and the hole is filled so ambient air from within the walls doesn’t affect the sensor

The other is the actual tolerance of the sensor and here is the table of typical values of resistance to check that remote temp sensor and see if it is within range

To measure this you have to get on the roof and take that AC cover off and locate the gateway and remove the remote temp sensor and then measure the resistance valvular at the plug end if the wire..

Also if the connection is not secured or has some corrosion it can affect the overall resistance read

[RickV]

I have some grey anti-head splitter tubes for the corners of the slides can I use that so if need to change out the sensor I can remove it or use expanding foam.