AC Thermostat Control Panel Question

I have a question that I cannot seem to find the answer for. I have a cruise air system in my boat with a remote panel for temp control. Raise the temp and the heat cuts on...lower the temp and the AC comes on. The frustrating part to this is that I cannot select heat only, or cool only. Based on the temp I set it at will determine if it is heating or cooling. Ideally, I would like to be able to just select heat as winters nights in this area get down low, but the day it gets up into the 60s. When not at the boat, I only want the heat to come on. Is there a replacement thermostat for this system to allow me to select the heat or cool only function? Any of you had this same frustration? This is a link to what my panel looks like:

http://www.tampabaymarineair.com/mediac/450_0/media/passport-io.jpg

Thanks for the help!
Scott

I have what looks like the same control panel but it was an after market unit. Can't recall the brand right now. But to switch from heat to cool to both, on our unit, hold the power button in until P01 appears on the panel. That is the setup for mode. Push the up/down buttons to select "1" for cool, "2" for heat and I guess "3" for both. Then push the on/off button again and it will display the firmware version. I'm not on the boat right now so I may have the numbers reversed but our panel shows a blue star if in cooling mode and a red symbol if in heating mode.


If this doesn't work, I'll be on the boat tomorrow and have access to the manual, so let me know.


Bob

We have two units on our boat. The one in the salon works like you described, no dedicated heat or cool buttons. The one in the aft cabin had the controller replaced by the previous owner. It has all the settings you would expect. My AC units are 1989 Marine Air System C16H. As far as I can tell it is just connected with a phone cord connector.
New Digital Programmable Thermostat

n36511 said:

I have a question that I cannot seem to find the answer for.

Thanks for the help!
Scott

Click to expand...

I have the same boat and thermostat. Bob H is right you can select heat only by programming as he described.

You can probably find the manual on the Dometic web site.

timjet said:

I have the same boat and thermostat. Bob H is right you can select heat only by programming as he described.

Click to expand...

I agree except the P01 settings available are: 0 is automatic heat or air, 1 is air conditioning only, 2 is heat only, and 3 is for some system I do not have.

That was off the top of my head, I never used the auto mode, I just remembered the 1 and 2.


Sorry for the confusion,


Bob

All, Thanks for all of the replies!! I greatly appreciate it. I will be at the boat this weekend and will give this a try and report back. I knew you all would have an answer.

Thanks -Scott


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timjet said:

I have the same boat and thermostat. Bob H is right you can select heat only by programming as he described.

Click to expand...

Ditto. We have the manual on the boat that gives all the codes, including dehumify mode. It isn't simple so we always have to look at the manual when we make seasonal changes. PM me if you want me to bring the manual home this weekend and scan it for you.

Figured it out

So I wanted to circle back and let you know what I discovered so that others can benefit. First off, thanks for all of the replies!! Fantastic forum!

I made it to the boat this weekend and attempted to change to heat only mode. Unfortunately, it did not work for me. When holding the power button on, mine shows up with a "U" and I could not enter programming mode. After much research, I was able to find documentation on my thermostat and programming. It is called a passport II and programming is different. Attached is a small manual that I put in word format on how to program this type of unit.

Marine Air model Cmcp16k

The programming instructions you posted say press the power button until the U shows then release and you get 0,1, or2, followed by U1. Use up and down to change from 0 to 1 to 2. 2 would be heat only. What's the problem?

obthomas said:

The programming instructions you posted say press the power button until the U shows then release and you get 0,1, or2, followed by U1. Use up and down to change from 0 to 1 to 2. 2 would be heat only. What's the problem?

Click to expand...

Not much of a difference but the step "TO UNLOCK PROGRAM MODE: After entering the program mode, simultaneously press and release the POWER and DOWN buttons." was unknown and is a different than described above. No problem. Just wanted others to know that searched for this same solution.

Thanks

[STRIKE][/STRIKE]

n36511 said:

Not much of a difference but the step "TO UNLOCK PROGRAM MODE: After entering the program mode, simultaneously press and release the POWER and DOWN buttons." was unknown and is a different than described above. No problem. Just wanted others to know that searched for this same solution.

Click to expand...

That's what I was missing,

I have the same unit as Dave. It is a replacement to the original which failed. I like the way it works. The only issue I have with it is the fact that at night or in the dark you need a flashlight to read the buttons. You would think that after ten years with the unit I would have memorized the button locations and functions but in some years I only use the air or heat a few times. The Admiral almost never touches it.

pete