Advice on replacing both rooftop ACs with heat pumps

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Advice on replacing both rooftop ACs with heat pumps

July 18, 2018, 04:57:27 am

Both 21 year-old roof ACs, Dometic Penguins, are dripping water into the coach, even after gently tightening the gasket, so I took the plunge and ordered:

- Dometic Brisk II Air heat pumps, model B59186.XX1C0
See Dometic Brisk II Air | Dometic
- Ceiling assembiles
- Thermostat, Comfort Control II
- Multi-zone control kit

A few questions:

What have I done? PPL Motorhomes was having a sale, so what's an avid Foretraveler to do?
Would the existing communication cable, 12V and 115VAC wiring and remote temperature sensor work?
Would this come with new gaskets?
Anyone want the old ACs?
How quiet are the new-generation AC units?

Any advice on this upgrade would be appreciated.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #1 – July 18, 2018, 09:10:52 am

I have not changed out the units on our coach yet but have over the years changed out units on the other RV's I have owned and have helped friends, so

Yes 120v wire will work
they come with gasket.
LV wire will work on connecting up but may need a special board for them to talk. Seems every time we have done one, something had changed on the controls.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #2 – July 18, 2018, 04:12:37 pm

I had my units replaced about 18 months ago with the Penguin II heat pumps. They were able to use the existing 110 and 12 volt (telephone-type with modular plugs) wiring, as well as the remote temp sensor. All that was needed was setting some DIP switches correctly for the configuration.

These Penguin II units are a big disappointment in noise. With the compressor running in cooling mode they are substantially noisier than the old units and it gets even worse in heat pump mode. I understand that this might be the Penguin design so the brisk airs may be better.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #3 – July 18, 2018, 05:28:11 pm

The Dometic Brisk II Air marketing states:

- Less vibration and noise
- 30% more airflow
- NASA inspired

I believe their is a three-speed blower. However, the compressor noise may be louder than fan noise. We will see.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #4 – July 18, 2018, 05:56:13 pm

We're still using our original Penguins, so at the moment only asking out of curiosity (knock wood):

I have read that with the the "heat pump" style roof air conditioners, the air distribution fan has to run all the time the unit is turned on. Is this true for all brands and models? I always figured it is the fan vibration and noise that most people find annoying...at least with the older style A/C units. Just wondering if having the fan running all the time is objectionable.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #5 – July 18, 2018, 06:16:19 pm

Quote from: Chuck & Jeannie – July 18, 2018, 05:56:13 pm

We're still using our original Penguins, so at the moment only asking out of curiosity (knock wood):

I have read that with the the "heat pump" style roof air conditioners, the air distribution fan has to run all the time the unit is turned on. Is this true for all brands and models? I always figured it is the fan vibration and noise that most people find annoying...at least with the older style A/C units. Just wondering if having the fan running all the time is objectionable.

Chuck, I have the Penguin 2's with the ccc thermostat, heat pump cycles fan on and off just like it does in ac mode.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #6 – July 18, 2018, 09:01:00 pm

Quote from: Chuck & Jeannie – July 18, 2018, 05:56:13 pm

Just wondering if having the fan running all the time is objectionable.

One word: "YES". Maybe it's quieter in the coach, but it's obnoxious to neighbors!

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #7 – July 18, 2018, 10:31:43 pm

I purchase (2) Dometic Penguin II 15,000 BTU's heat pumps high capacity this year from PPL with the new CCC t-stat. It had everything needed to replace the old units including the base gaskets. Yes I believe they are a little louder with the fan speed on high but once the inside temps come down the unit switches to medium speed so it's not to bad.
But everyone ears are different so I took some readings of the old units to compare, see as follow;

Old unit were Dometic Penguin Heatpumps and using a downloaded decibel meter app on my phone and a airflow meter.
Nothing on-------42 decibel
Fan speed high --68 decibel - Airflow 410 cfm over the driver seat vent.

New units
Nothing on ------41 decibel
Low speed-------67 decibel - Airflow 400 cfm over the driver seat
Med speed-------68 decibel - Airfow 450 cfm
High speed-------71 decibel - Airflow 475cfm

Nothing on but generator - 56 decibel for comparison.

Two things that I consider was the ease on installation with existing wiring (telephone T-stat cable had to have new 4pin plugs crimp on) and components such as reusing the interior grill also being in Arizona I wanted the largest capacity for pull down and airflow and that's what I got. As an side note I made an baffle that fit into the discharge air plenum that better directed the airflow to the side ducts, by doing this it reduce the turbulence in the plenum box and thus reduce the noise an little.
Steve

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #8 – July 19, 2018, 02:44:00 am

Quote from: mike leary – July 18, 2018, 09:01:00 pm

One word: "YES". Maybe it's quieter in the coach, but it's obnoxious to neighbors!

I have 2 Atwood 15,000 btu units with heat. Outside the RV I can't even hear them running, Not too bad inside either.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #9 – July 19, 2018, 08:45:54 am

Thanks for the replies. My Dometic Brisk II Air units have not shipped yet, but here are a few comments:

1. Quieter?
I guess Dometic can claim their air conditioner is quieter if it has just one decibel reduction in noise, which is almost imperceptible. Dometic's website states: "...great care has been taken to reduce operating noise: with the motor, compressor and evaporator bracketed together for vibration-free, quiet operation. Long copper lines and dual rubber bushings are also responsible for minimizing noise and vibration. Allowing you to enjoy comfortable temperatures in peace and quiet!"

This surprisingly gives away some trade secrets. With all the claims of being quieter, I should publish the "before" and "after" noise levels. I do not have a DB meter, but perhaps there is a good app for that.

2. Old Telephone Cord
I am not sure if the 21 year old telephone communication cord with the RJ11 connector will have enough of the six possible wires populated. It could be challenging to pull another cable through the coach.

Or maybe I'll get lucky and only need to replace the old connectors by crimping on new connector using the extra existing conductors?

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #10 – July 19, 2018, 09:00:44 am

In response to noise questions, we leave our fan on either low, medium, or high (not Auto) when using the Penguin II's. It's more like a "white noise" and we don't hear both the fan and compressor abruptly coming on in a quiet coach. We find that we don't have to raise and lower the TV volume every time fan turns on. Works for us, YMMV

Ed

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #11 – July 19, 2018, 11:05:03 am

I think it's 'brand dependent', as well. Our Carriers are whisper quiet, where our Colemans could wake the dead!

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #12 – July 19, 2018, 12:17:28 pm

Now that Dometic owns Atwood, when they make the Air Command AC units compatible with the CCC control thermostat I will
think about changing my units.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #13 – July 19, 2018, 12:31:00 pm

I think most of us are in search of the quietest air conditioner. So which one is it?
I still have the original 1999 units but may be replacing the front 13.5kbtu unit soon. Probably upgrade to a 15kbtu.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #14 – July 19, 2018, 01:08:07 pm

Do the heat pumps blow cold or just cool?

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #15 – July 19, 2018, 01:10:09 pm

Starts out cool then warms up as it goes.. 10 min its warm in the coach

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #16 – July 19, 2018, 01:15:19 pm

Quiet inside does not mean quiet outside. Some of the new and improved AC units just move the noise to the outside of the coach where they annoy everyone within a half dozen spaces.

Newer Phaeton's with Coleman Mach 8 AC units are particularly annoying and because most of them are very dark colors the AC runs all day. The newer Cornerstone's are the same. Whatever ambiance there might have been is destroyed by these howlers.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #17 – July 19, 2018, 01:32:37 pm

Just had a Foretravel owner in my coach this week and, like ALL other visitors, he commented how much quieter my Attwood A/Cs were than his, 15,000 btu heat pumps.

Thanks again to Kemajohn for the heads up that steered me to these quiet A/Cs

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #18 – July 23, 2018, 02:29:28 am

Best & Quietest RV Air Conditioner of 2018 Reviews

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #19 – July 23, 2018, 10:07:24 am

If you go with heat strips instead of heat pumps you won't have to listen to the compressor when in heat mode.
Also you won't have the valve to possibly have to repair that reverses the system between cool and heat.
And they will provide heat at the lower winter temperatures some of us encounter.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #20 – July 23, 2018, 10:27:45 am

I don't believe heat strips are available on the high output (15000 BTU) penguin II units. Please correct me if I am wrong.

I replaced one of my units with penguin II which required replacing the 4 button wall thermostat and the control board on the old unit.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #21 – July 23, 2018, 11:09:53 am

I am skeptical about the "Best RV AC" article. It's really just a link farm with company literature. There is no basis for the ranking, no comparison, no Decibel measurements. However, I did choose their top pick. After seeing their modern design improvements, I was sold. Two Brisk II Air units are enroute via freight.

I will review difference between the 21 year old units and the new ones.

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #22 – July 23, 2018, 05:37:40 pm

Tim - did you happen to get decible readings before you took the old units off?

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #23 – July 23, 2018, 09:36:08 pm

Dometic RV Air Conditioner Showcase - YouTube

Re: Advice on replacing both rooftop ACs with heat pumps

Reply #24 – July 24, 2018, 06:22:47 am

Will watch your thread here Tim. Have the original AC units I believe. They don't cool much up front, and at high speed are pretty loud outside as well as inside. Will be replacing them at some point.
John, look at the comments below the youtube video. Not well received it seems.
Wish Foretravel had ducted them more forward to the drivers area.
The other issue I don't like is the condensation just runs off the roof, wish there was a better way of managing it. Right now, here in humid south Texas, a lot of water runs off the front of the coach, into the step.
With aqua hot, not sure why a heat pump is needed. But not all coaches have it so...

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