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time2roll's avatar
time2roll
Nomad
Mar 23, 2013

Dometic digital thermostat

Been wanting to go with a digital thermostat but I was not very excited about using the battery powered home units for the conversion. Then found out Dometic has a new thermostat and control board.

So if you have this thermostat:



And you want something like this:
(I fixed those extra holes BTW)



Here is the kit:

Dometic Single Zone LCD Control Kit w/ Thermostat White 3313189.000 $75

Here is the kit pictured:

clockwise from top left. freeze sensor, spade terminals to crimp onto your furnace control wires, wall thermostat, mounting screws, control box, wire harness.



This is the old box up in the air unit



Here is the new box. Much smaller should also allow better air flow through the inlet filter.



Old box with the gaggle of wires. Actually fairly simple.

Paired white/black are 12v supply.
Blue/white is control connection to furnace.
Yellow is 120v power bundle.
Black to the left is the freeze sensor.
Brown is the bundle from the old thermostat.

Everything is either cut or disconnected to remove the old box.



New box connected to romex



The kit comes with a wire harness to connect to 12v and the thermostat cable. Only three wires are used for the new thermostat. 12+, 12-, & one control wire. I used Red, Black, Orange as that matches the harness.

This is the new box with snap connectors:



The heater control wires connect to the two spade terminals on the left. Thermostat control harness snaps into the four pin middle connector. Freeze sensor on the two pin connector to the right. Romex goes in at the far right. Power and control to the air conditioner uses oem harness that plugs in on the back side.

Worked perfect right out of the box. Well OK I had to buy some spade connectors as the oem wire to the furnace was a larger size. And some crimp connectors (not included) to connect the 12v thermostat harness.

Here is the user manual for those that want more operating details:
Dometic single zone digital operating instructions


Inspired by member BuffaloIndian in this thread:
Anyone Replaced Dometic Thermostat: Analog to Digital?
  • PJMAX's avatar
    PJMAX
    Explorer
    Apr 18, 2013
    I enquired about getting one of these stats and was told I need my unit make serial number and model number. Are these the right questions or just as long as it is a Dometic it should work? PJD
  • ryanallie1's avatar
    ryanallie1
    Explorer
    Apr 15, 2013
    smkettner wrote:
    I just have a preference to everthing running off 12v. I realize if you change batteries once a year all is fine. The add-on fan switch also is just not my style. BTW the Dometic has an automatic fan speed setting. Nothing wrong with the lower cost thermostat. It may even have more features like programability to set back temps based on time.

    I did have a delay on the blower fan start to let the compressor start by itself on a marginal generator. That feature is now gone but I have found I really will not be using a generator to run the air for extended periods. At that point we are looking for hookups.

    The price did not bother me a bit. Same as if the fridge control board went out I would not opt for a lower priced board if it relied on batteries. Reminds me it is time to change batteries in the smoke detector and CO detector :R Why can't those be 12v connected?

    I also found the existing freeze sensor in a bad spot. The new sensor seems better IMO and I have had an issue a few times.

    Anyway it is just another option if considering a change.



    Hi All.

    So, What is stopping you from doing just that ?. Our Motorhome has everything hard wired to the 12 Volt System. I went out and bought all new "Batery Operatd Units",

    We have Double of everything now, except for the "Smoke Detectors", we have if I remember correctly about 7 Smoke Alarms. As fast as an RV Burns to the ground, its nice to have a few extra "Smoke Alarms".

    They do give you a bit more notice if there is a fire inside of our Motorhome. Works out for us anyways.

    Good Luck. Happy Travels. Dan & Jill
  • time2roll's avatar
    time2roll
    Nomad
    Apr 08, 2013
    The single zone thermostat that I installed is not programmable.

    Although it is rather easy to use. This weekend DW had the air cranking before I could get the stabilizers down. So much for showing off the new thermostat. It worked beautifully and maintained temperature perfectly. Certainly far better than the old style.

    BTW don't have a vent pointed right at the thermostat :R
  • john_b1's avatar
    john_b1
    Explorer
    Apr 05, 2013
    downtheroad wrote:
    Nice mod and nice write up.
    I looked at them and was interested but just didn't like the price as compared to the $25 I spent on mine + the $3 for a high low fan switch.

    Just wondering why you were, "not very excited about using the battery powered home units?"



    I started putting programable t stats in my units starting in the early 2000s as those $2:00 factory junk units do nothing to maintain a heat level..
    My current unit has a dometic do it all and I sure would like to have my old type units back in here,my wife sat for an hour or more reading to try to figure out how to just do the very basic functions with the blame thing. It now works OK but not inpressionable to me !!Keep things simple because if they aint broke why fix them..
  • lj2654's avatar
    lj2654
    Explorer
    Apr 05, 2013
    Katysdad, I just had my thermostat replaced and was told the analog is no longer available. New digital works great and much more precise....
  • katysdad's avatar
    katysdad
    Explorer
    Mar 24, 2013
    Was told by parts dept that the analog thermostat is no longer available from Dometic, that you must use the new upgrade kit now if replacing the thermostat. Anyone else heard this?
  • motorcycle_jack's avatar
    motorcycle_jack
    Explorer II
    Mar 24, 2013
    I guess some units use batteries but my two zone setup has the thermostat wired into the RV's 12V. so no battery. Same with the fire and CO units. I learned something - I thought all RV's were wired this way!
  • time2roll's avatar
    time2roll
    Nomad
    Mar 24, 2013
    I just have a preference to everthing running off 12v. I realize if you change batteries once a year all is fine. The add-on fan switch also is just not my style. BTW the Dometic has an automatic fan speed setting. Nothing wrong with the lower cost thermostat. It may even have more features like programability to set back temps based on time.

    I did have a delay on the blower fan start to let the compressor start by itself on a marginal generator. That feature is now gone but I have found I really will not be using a generator to run the air for extended periods. At that point we are looking for hookups.

    The price did not bother me a bit. Same as if the fridge control board went out I would not opt for a lower priced board if it relied on batteries. Reminds me it is time to change batteries in the smoke detector and CO detector :R Why can't those be 12v connected?

    I also found the existing freeze sensor in a bad spot. The new sensor seems better IMO and I have had an issue a few times.

    Anyway it is just another option if considering a change.
  • downtheroad's avatar
    downtheroad
    Explorer
    Mar 24, 2013
    Nice mod and nice write up.
    I looked at them and was interested but just didn't like the price as compared to the $25 I spent on mine + the $3 for a high low fan switch.

    Just wondering why you were, "not very excited about using the battery powered home units?"

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