2006 Marlin Air Conditioning Control unit / Thermostat

Ralph163

Well-Known Member
Joined
Jan 21, 2022
Messages
79
Reaction score
11
Points
8
Age
55
Model
Marlin
Still going through this "new to me" Marlin.

Seems like the thermostat is reading a lower than actual temperature and shutting off the compressor to soon. Ambient temp in cabin is 75 (according to handheld thermometer) but the thermostat is reading low at 64-65 deg. At 65 the compressor does not turn on since it sees no reason to cool. I am guessing the thermostat/control unit needs to be replaced? Anyone know where I can get one of these?
 

Attachments

  • IMG_8467.JPG
    IMG_8467.JPG
    325.5 KB · Views: 2
I'm not familiar with that control at all but if it has any kind of a setup menu maybe you can calibrate the temperature readout.
 
Still going through this "new to me" Marlin.

Seems like the thermostat is reading a lower than actual temperature and shutting off the compressor to soon. Ambient temp in cabin is 75 (according to handheld thermometer) but the thermostat is reading low at 64-65 deg. At 65 the compressor does not turn on since it sees no reason to cool. I am guessing the thermostat/control unit needs to be replaced? Anyone know where I can get one of these?
I have found the cold air outlet is beside the thermostat and get the wrong temp, I put a roll of paper towel between the cold air outlet and t-stat, works fine now.
 
I have found the cold air outlet is beside the thermostat and get the wrong temp, I put a roll of paper towel between the cold air outlet and t-stat, works fine now.
Funny, I had thought the same thing. I even tried putting tape over the sensor since it's so close to the vent.

But I notice that my thermostat is 12 degrees to low when compared to an accurate thermometer I put next to it. I definitely think it needs to be calibrated or replaced.

After some Google and GreatGrady searches, I found out the unit my 2006 has is a Dometic Vector Series with the Dometic Passport Cabin Control. And there is a custom program (P5) that lets you set the "Inside Air Temperature Sensor Calibration" (page 17). It's pretty confusing, but I will read up on it tomorrow. Seems like it gives you +/- 10 of adjustment. Will keep you guys posted.

 
Update: Seems like the previous owner had already adjusted the sensor calibration to the max. Dometic very helpful. I can add an external sensor or replace the display. Now I know why the previous owner said the AC was good, but not great. It had been shutting down 10 deg before it reached it's mark.
 

Attachments

  • IMG_8506.JPG
    IMG_8506.JPG
    912.2 KB · Views: 5
Yes, exactly. You don't have the remove all 4 screws just loosen enough to pull the panel off the bracket.

I went in thinking I was adding the remote temp sensor but it turned out there was already one existing. It's located behind the vent under the stairs.
 
I'm not sure my thermostat has a sensor on the bezel like I read it does. I'm thinking the original unit always had the aux temp sensor.

FYI, you can go into the programming - https://productimageserver.com/literature/ownersManual/88006OM.pdf and put the system into a test mode which will run heat for 10 mins, fan for 10 mins, and AC for 10 mins. This will confirm the sensor is bad if it does blow cold during the test.
 
  • Like
Reactions: Ralph163
The tech just told me, once you plug in the remote sensor, it supersedes and overrides the one built into the display. So in actuality, I could simply disconnect the remote sensor and the display sensor will take it's place. But I already ordered the remote sensor, so I will wait to install that.
 
  • Like
Reactions: athomp228
We got this control unit for our 2007 305 Express, plug and play and is much better than the factory one. Easier to navigate to change settings, looks better and being able to set a schedule for unit run time and temp is sweet. We have it set to stay at 80 degrees during the week but on Friday it drops to 70 at 2pm so boats cooled off for us. Not sure that's important to you but wee sleep on ours every weekend during the season.

And I have a extra remote temp sensor if you need it. Band new just pay to ship it.