Cabin temperature not correct on Passport I/O controller

[rappja]

I have a 2019 R-31CB LE. Now that it is cold, I have been using the reverse cycle A/C heater.
The unit works well, but the temperature on the controller is way off, showing temps in the 50's when it is 70+ in the saloon. Therefore, the heat never cycles off.
Thinking the controller may be bad, I took it off the wall (it is stuck on, not screwed). the cable was plugged in corrctly. I took a picture of the back to get the part number, but I can't find any reference to that number online. There is a current Passport I/O controller being sold that looks exactly like mine, but has colored buttons (mine doesn't)
So my question is, has anybody had this problem or knows about it. Can I simply get a new controller, and plug and play it (is it compatible with my 2019 A/C unit)? That would be easy, as I can return the new one as long as it has the original packaging, etc.
Alternatively, could this be another problem?
Thanks for your help.

 

[Rauguthj]

On our 2024 R31 CB with Webasto units, the sensor probe was installed out of position, stuck under the AC unit. Temps were wildly inaccurate. When placed in the air intake grills, temperatures were much better.

 

[rappja]

On our 2024 R31 CB with Webasto units, the sensor probe was installed out of position, stuck under the AC unit. Temps were wildly inaccurate. When placed in the air intake grills, temperatures were much better.

Thanks for the info. When I get to the boat, I'll try to find the sensor probe. If it's not in the air intake, wher do you think I should start looking?

 

[Mastercraft]

Not sure about the 2019 R31 LE. Here is what I did for 2017 R29 NW:
1) moved temperature controller from cave to left side of berth entry, upgraded to 3.0 control.... not easy to fish wires!!!
2) added cabin air intake under wine cooler (just two feet of 4" straight duct)
3) moved temp sensor from Webasto unit to 3.0 controller
4) added 1" foam tinfoil board between Webasto and fridge and kept clear of hot exhaust (for noise reduction and keep heat away from fridge)
5) added Webasto 1" dia intake combustion muffler (sold by Webasto)

Default temp sensor location is on Webasto. No wire harness had a temp sensor that goes from 3.0 controller to Webasto.

Check to see if your temperature controller senses temp at controller or at Webasto. Use a hair dryer on low pointed at controller to check this.

Webasto was running off bilge air temperature and using bilge air to heat. Totally stupid!!!! Now life is great with the modifications..... consistent temperature and 3-5db quieter

 

[rappja]

I don't think we have the same layout, as you said. My boat is a 31. Also, if you have the NW edition with a Webasto, I think I have a different unit, which is a reverse cycle A/C and heater.
Good idea about pointing a hair drier at the controller. If I can find it, I'll do the same to the sensor

 

[Rauguthj]

On our 2024 R31 CB with Webasto units, the sensor probe was installed out of position, stuck under the AC unit. Temps were wildly inaccurate. When placed in the air intake grills, temperatures were much better.

Thanks for the info. When I get to the boat, I'll try to find the sensor probe. If it's not in the air intake, wher do you think I should start looking?

the probe on ours was tucked under the unit, and required much effort to find and place in the proper location. For the unit in the cave, access was easy. For the forward unit, we had to pull the refrigerator to gain access. This picture is from the installation manual.

 

[rappja]

Thanks. That helps.

 

[rappja]

I have solved the problem. I found the electric control box for the unit (in my 2019 RT-31 it's behind the fan grill in the salon just before the steps leading to the main cabin). I removed the grill (4 screws) and pulled it out of the way as much as possible, with it still connected. The black control box has a thumb/phillips screw holding the cover on. After removing the cover, there are 2 plug in phone type grey wires. Trace the one from the sensor and unplug it. I just left it there, then replaced the cover. This was the hardest part, as it was difficult to get the retaining screw back in place. It would be much easier if the electrical wires and hoses to the fan were disconnected, but I elected to be lazy, and not create a new disaster.
After that, the unit worked perfectly, reading the temperature in the salon, and using the built in thermostat in the control panel. It turned on and off as expected.
This begs the question of why did Ranger Tug go through the extra work and expense of using the second sensor in the wrong place? Also, don't a lot of other owners have the same problem? I still think I'm missing something.