Older duo therm control unit upgrade

[Boatman57]

Hey everyone,I have an older Monaco coach.2001. To be exact.had some issues late last year with rear unit.after shutdown sounded like water running in the unit had to trip breaker to stop it.was educated on this site by some great folks who explained the control unit was suspect.found out my part number was NLA of course.older # was 3107541.009 new # is3316230.007.it comes with digital thermostat and very sparse directions.dont think it's gonna be a plug and play.any advise is appreciated tks

[RKins]

Is it the 4 button control (more than likely). Attached is some information.
If you need more help let me know.

[Boatman57]

Good morning sir,tks for the reply.i have enclosed a pic of the thermostat that came with it.obviously the economy unit but hey if stuff happens when you push the buttons woo hoo!

[A1RVTraveler]

If you are replacing an older "sliding bar" style thermostat with the newer style shown in the picture, you also need the gray control box 3316230.700.
There is some wiring rework needed.

The new thermostat only uses three wires.
12V Positive - Use Red
12V Ground - Use Green or White (I choose Green)
Communication - Use any other color - I prefer the yellow.

Replace the control box in the ceiling assembly.
You have the (3) 120VAC wires to move to the new box.
You have two wires for the 12V coming to the new control box. This is the 12VDC source from the RV fuse panel.

You have a bunch of small wires (6 colored wires in a thermostat harness)
The connector on the new control box has a four-wire connector.
Red - Power to control box 12V from your fuse panel.
Black - 12V Ground- This is a little tricky. You need to attach this wire to the 12V Ground for the RV and also connect to the 12V ground wire going to the thermostat.
I choose green from the 6-wire harness.

Orange - Goes to the communication wire at the new thermostat. I choose yellow.

Red and White stripe wire. Goes to the 12V positive to the thermostat. I choose red.

You also have two blue wires in the ceiling assembly that go to the two furnace connections on the control box. You get wire connectors in the kit.

There is also a new freeze sensor that comes in the kit.

Hire a professional if this is more than you want to tackle.

I also suggest you turn off the 120VAC to the control box before you start and also pull the 12VDC fuse that powers the control box.

Good luck.

[Boatman57]

Yessir,you nailed it..whole kit was under 120.00.the install directions were sparce at best and you covered all my questions quite well sir.many tks for your time and for sharing your expertise.heres to many miles of safe. Travel for you and the family.

Boatman57