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Topic: Dual A/C replacement (Read 644 times) previous topic - next topic

Dual A/C replacement

I'm getting ready to get a new front A/C unit.  The rear has a relatively new DuoTherm Penguin. Was going to get another Penguin 2 for the front.  My question is, does it have to be a specific unit ?  They are both controlled by the same thermostat controller next to the driver seat and that also controls the 2 furnaces. 
Does it have to be a specific model with a special circuit board?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Dual A/C replacement

Reply #1 –
what thermostat do you have now?

New units will have the new board.. you will need either

A) new thermostat Comfort Control
B) adaptor board to the new ac for the old 5 button.

Get the Duo Therm 15k (regardless). always go the larger one for max cooling

Re: Dual A/C replacement

Reply #2 –
I just finished replacing both A/C's.  Here is my story:  I had decided to replace the original DuoTherm up front with a new unit.  I just assumed that would it could be plug and played.  I had no idea concerning control boards and boxes..Decided on Dometic Brisk II because of the price; PPL has good prices with free and quick shipping, btw.  When I got the new ac, I discovered that it had a plug and no other wiring.  So I nosed around the internet and figured out I was missing a part; the controller.  On the phone with Dometic, discussed my set-up, and discovered that I would need to upgrade the tstat from a 4 to a 5 button, also the circuit board for the old ac for the two to work together. Ordered a control box for the new ac, and the upgrade kit, which includes a 5 button, circuit board, a freeze sensor for the old ac.  Dyers RV Parts has good prices on Dometic parts, btw.  Once I received all of the parts, and after looking at the wiring from the coach, I decided to hire an rv ac guy to help with the install.  He installed the new ac along with replacing the board in the old unit, and wired every up.  He needed an extra 'telephone cable', so I provided one.  Not an RJ11 cable.
Couldn't get the two ac's to work together.  Tstat not working properly.  We gave up after several hours to regroup.  I then decided to ditch the old ac, and get another Dometic BA2 and control box.  Was able to use the 5 button from the upgrade kit, but nothing else.
My ac guy came back, installed new ac, along with a real RJ11 cable. 
Happy to report everything is working properly, and I have 2 new ac's.  The Brisk II's really put out more airflow than the old units.  Along with the airflow, comes the wind and fan noise from the units.  Not any louder than the old units, but not any quieter, either.  Could it have worked with a combo of the old and new, with them properly wired with an RJ11 cable instead of a 'telephone cable'?  I'm thinking it maybe could have, but I'll never know.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: Dual A/C replacement

Reply #3 –
As a side note upgrading to 15KBTU units will prevent you from running in 30 amp service which many state parks have. There are soft start units that can be added but I don't personally have experience with them.
2002 U270 34' Build 5953
Cummings ISL400HP
3410 Floor Plan
Longview, TX

Re: Dual A/C replacement

Reply #4 –
I added a soft start to my front ac. That and the assist from the victron inverter and lithium batteries means I never have to worry about that. I can easily run it from 30 amps.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Dual A/C replacement

Reply #5 –
Quote from: Bob and Julie –
I added a soft start to my front ac. That and the assist from the victron inverter and lithium batteries means I never have to worry about that. I can easily run it from 30 amps.
If I put my fridge on gas and turn off my victron inverter/charger and electronics inverter, I can run my front Penguin 2 15000 btu with micro-air on a 15/20 amp circuit.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Dual A/C replacement

Reply #6 –
Mark,
You might want to contact Dometic.  I replaced the rear unit last fall.  The guy who installed it was very familiar with the swap.  He said I would have to use the board out of the old unit or pay additional 70 dollars for a new board like original.  The board that comes in new penguins is different.  So I told him to order the board.  He put  it in on the ground, put unit on roof and it was plug and play.  Very easy swap.
Keep us posted how it works out.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Dual A/C replacement

Reply #7 –
It will work for a while, but it will max out a 15 amp circuit and the wiring will get hot and drop the voltage to 109 Volts or less. I switched to a 50 amp circuit to prevent my feed wires from melting.

Agree with you on the noise. I should have designed a 115VAC mini-split system. It's much more quiet, efficient and heats down to 32 degrees.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.
 

Re: Dual A/C replacement

Reply #8 –
I will say you can hardly hear the Atwood working in mine. So quiet I can hardly stand it.. now I have no reason to not answer back when the wife talks