Roof air replacement

[Mike in GA]

Have three DuoTherm low profiles, rated at 13.5 btu. They are 12 or 13 years old. The front never blew as cold as the rearmost, and now it has quit. Last year we had to replace its start capacitor. It probably went again. An RV a/c man will check out on Friday. The middle one is fair-average.
      All three are controlled by a three station thermostat, and the front a/c apparently is the 'brain', relaying the signals from the thermostat to the other two a/cs.
      I am inclined to replace the front two and keep the back one, but I am told that the rearmost may or may not be compatible with new a/cs.
     Two questions:   1) If I stick with Duo-Therms, should the rearmost one be compatible and work off the existing three-station thermostat?
2) If it is not compatible, can I run the rear one independently, off a second, dedicated thermostat?
     Thanks in advance for your input!
Mike in GA

[TomC]

I have heard the same thing. Run the rear A/C with your old thermostat and buy two new ones for the front and run them with the new thermostat. Are these ducted? Then you'll have some redundancy if one system craps out. Good Luck, TomC

[Lin]

What Tom said!  I would assume that the rear one is the bedroom, which would be nice to have work independently.  However, if all three are ducted into the same system, that would change things. Also, if I were replacing my AC's, I would put a 15,000 BTU up front t get a little more air up front for OTR use.  The bedroom would do fine with a smaller, quieter unit.

[luvrbus]

I believe it is a new ball game with the new Penguins 11 I wasn't able to replace my older Penguin low/pro from CW so I had to buy the newer Penguin 2 model Lo/pro they seem to be a better unit with a lot of new features

FWIW I have a new 3 speed motor with the new style mounts and the 2 fans made of metal that replaces the junk fans made of plastic for the older unit never installed still in the boxes yours for 100 buck plus the shipping I sold the shroud already

good luck

[Mike in GA]

Thanks for the advice so far. Should have mentioned that the three airs are ducted.
Mike in GA

[tomhamrick]

Hi Mike,

Check with Nick Badame on this board. He was a great help to me when I had to replace one of my Penguin units.