Domestic Thermistor/KIB Display Panel Temperature Offset Question

[GUS2000]

Noticing that the thermistor readings that are displayed on the mid ship KIB panel are a few degrees off of the actual temperature (taken with a calibrated thermometer) in the bedroom of the 4369.. Room temp is 66 and panel reads 69. Is there a way to change the offset on one thermistor/temp reading somewhere so that the readings are more accurate??

 

[flyboy013]

I had a similar problem with my bathroom thermistor. I have Silverleaf in my coach and with Art's help was able to resolve the problem. While you have KIB instead of Silverleaf, I believe the solution will be the same.

My temperature was reading 5° too high. It was determined that I could use a 630 ohm resistor to lower the temperature reading to the actual temperature. On my coach the thermistor plugs into the Temp2 connector of the TM250. The wires coming off of the Temp2 connector has spade terminals. I took a resistor (I don't recall the value but it was as close to 630 as I could get) and put spade terminals on each end and then covered it all except for the space terminals with heat shrink.

Not sure what type of thermistor is used (given that 630 ohms equated to 5°, I don't think they are NTC 10K). Given what I was able to get working, I would suspect you need an approximately 390 ohm resistor or you could add a potentiometer and dial it to the value you need.

 

[GUS2000]

I had a similar problem with my bathroom thermistor. I have Silverleaf in my coach and with Art's help was able to resolve the problem. While you have KIB instead of Silverleaf, I believe the solution will be the same.

My temperature was reading 5° too high. It was determined that I could use a 630 ohm resistor to lower the temperature reading to the actual temperature. On my coach the thermistor plugs into the Temp2 connector of the TM250. The wires coming off of the Temp2 connector has spade terminals. I took a resistor (I don't recall the value but it was as close to 630 as I could get) and put spade terminals on each end and then covered it all except for the space terminals with heat shrink.

Not sure what type of thermistor is used (given that 630 ohms equated to 5°, I don't think they are NTC 10K). Given what I was able to get working, I would suspect you need an approximately 390 ohm resistor or you could add a potentiometer and dial it to the value you need.

Thanks my friend... I think I will try the potentiometer! Im guessing that all of the thermistors terminate behind the display that is mounted mid ship?

 

[flyboy013]

Not sure about that. With the Silverleaf system things terminate at various modules throughout the coach and the display is just a user interface connected to the RV-C. Not sure if the KIB architecture is similar or if they terminate connections at the display as you are suggesting.

 

[GUS2000]

Gotcha.. I will start the easter egg hung and see if I can find the KIB modules lol
thanks man!

 

[NWIP]

I would try and reach out to KIB

 

[flyboy013]

I just remembered that the thermistors for the zones with Dometic HVAC units are wired directly to the HVAC units. The HVAC then reports the temperature to the thermostat which in my case is a Silverleaf TM510 module. Not sure if there is a thermostat "module" in a KIB only coach, but I suspect it works in the same manner. The only thermistors that are not wired to the HVAC units and instead directly to a Silverleaf (or KIB) module are the ones that don't drive an HVAC unit. In my case, that's the bathroom and outside. It was the bathroom temperature that I resolved with the addition of the resistor.

I just looked at the thermistor in my bathroom and the wire is only about 6" long. It then has a crimp connector for the wires that goes to the module. So you may be able to just add the resistor (or potentiometer) right there on the backside of the thermistor in lieu of the crimp connector.

 

[GUS2000]

Gotcha.. gonna pull the cover off and see how if there is a similar spade connection on the bedroom thermistor...

 

[Rich W.]

Just a thought but why not put the resister behind the thermistiser rather than at the display or AC unit? That way you can be sure you have the correct wire and even if your going to use a variable resister, they are probably small enough these days to stuff behind the thermister. Once “dialed in” you’d never need to adjust it again. My guess is that there is a way to calibrate the value within the KIB programming, or at least there should be, but I have no experience with those things.

Edit - I see this comment is a little late…