Installation of second A/C 34'Excella

[georgetexas]

Our 34'Excella has one A/C that seems to be working properly but is not able to keep up with 100deg heat in the Texas summers. Is it difffcult to install a second A/C in the rear roof vent. Is there 120v wiring at the roof vent. I plan to install a second 30 or 50 amp service. I do not believe swaping to a 15,000 btu A/C would be enough.

Thank you

[Dwight]

You can add the 2nd unit in the bedroom roof vent, but the 2 problems/challenges are the drain line and 120v power. There is 12v to the roof fan, but not 120v and no easy way to route the drain line in the exterior walls. I had the same situation on our 34' and decided to replace our 13.5 unit with a 15k unit and have been very happy. I did install a larger breaker panel and 50amp service and Marinco 50amp socket.

[vswingfield]

Originally Posted by Dwight

You can add the 2nd unit in the bedroom roof vent, but the 2 problems/challenges are the drain line and 120v power. There is 12v to the roof fan, but not 120v and no easy way to route the drain line in the exterior walls. I had the same situation on our 34' and decided to replace our 13.5 unit with a 15k unit and have been very happy. I did install a larger breaker panel and 50amp service and Marinco 50amp socket.

Hi Dwight,

I'm pretty much melting here in Little Rock and summer is just starting. The existing 13.5 unit struggles to keep the inerior the same temp as the exterion in the sun, and I have zero shade. What temp diferential are you getting in the sun with the 15k unit, and which model did you buy?

[Dwight]

I had the Dometic Penguin heatpump and replaced it with the same unit, a 15k instead of the 13.5k. I believe that Dometic only says they will cool to 20 degrees cooler than OAT. The 13.5k was "acceptable", but I had the opportunity to change to a 15k. The 15k seems to cool the same just on the low fan speed. If you currently have a "4 button" t-stat, then you will have to upgrade to a "5 button" t-stat if you install the 15k unit.
Dwight

[HowieE]

Dwight

What is the current draw on the 15 and are you running it on the #12 wire that originaly feed the 13.5?

[vswingfield]

Originally Posted by Dwight

I had the Dometic Penguin heatpump and replaced it with the same unit, a 15k instead of the 13.5k. I believe that Dometic only says they will cool to 20 degrees cooler than OAT. The 13.5k was "acceptable", but I had the opportunity to change to a 15k. The 15k seems to cool the same just on the low fan speed. If you currently have a "4 button" t-stat, then you will have to upgrade to a "5 button" t-stat if you install the 15k unit.
Dwight

Thanks Dwight,

Sounds like your Dometic was cooling better than my old Coleman. As for the t-stat, mine is a 1983. I have a knob on the unit itself. I am considering installing a wall unit as discussed in other threads.

[Dwight]

I am not sure what the current draw is, I will check it and get back to you with the figure. I am using the same wire with the 15k, all I did was add a new drain pan (which you can get from Dometic for about $49 made for Airstreams) and connected the wiring. I also bought a new inside ceiling duct and grille to have it match the new rooftop unit.
Dwight