Need new AC unit.

[Bob Bulot]

Getting a lot of good advice on this site.  Thanks!

I need to replace one of my Dometic 630516 roof airs.  This is a 15K BTU with a heat strip.  Does anyone know what the current model number is for replacing this unit?

Also, I'm considering a non-heat strip replacement, as I never use the feature.  Any opinions?

[Gerald Farris]

Bob,
I would look at the Dometic B59516.XX1C0. It is available on Amazon for $554 from several suppliers with free shipping. However, I am not sure that your current thermostat will work with any of the new replacement units, so you need to keep in mind that you need to check thermostat compatibility.

Gerald

[Paul Meehan]

Gerald,

With respect to reducing height clearance, would there be any concerns of going from the Penguin II to the Brisk II?  I believe the Brisk II is taller.

Thanks

[Joel Ashley]

Just as a precaution, Bob, are you certain the entire unit requires replacing?  If it's a bad compressor, that's a wash.  But if it's a start capacitor, a common fault, that's a relatively inexpensive repair.  I've got a bad AC also, and have yet to fix it, but was forewarned by a pro of that possibility, apparently a good one.

Joel

[Keith Moffett]

Bob, when you say 'heat strip' do you mean heat pump?  If so have you tried them?  I love the Aqua Hot but it uses fuel and requires maintenance.  When in a RV park we use the heat pumps and boy they are great.  They are our new best friend since we didnt have them on our last coach.
Just my 2 cents...

[Joel Ashley]

Have to agree with Keith on that.  One heat pump is a bit quieter, also, than several hydronic heat exchangers in the living area that we have to converse or hear the TV over.  That's especially if one can suffice with a pump running in another "room", letting its output leach through, and flow from ceiling ports.  At around 40 degrees outside, heat pumps stop because there's not enough heat for them to exchange;  but down to that point they're a great alternative to hydronics.

Surely Bob's Marquis came with heat pump AC's.  Such animals wouldn't have need for heat strips.

Joel

[Paul Meehan]

After recent reviews of AC units I see a few are available in three styles, AC only, AC w/heat strips and AC with a heat pump. 

Joel when you mention "Such animals wouldn't have a need for heat strips."  Is this based possibly that the heat strips would not perform well enough to heat the coach?  The reason I ask is I am about to change out one of my units.  Much like Keith I would like to reduce dependency on my Hydro-Hot and thought the heat strip option would be the way to go.  If the heat strips would not warm the coach then I should be looking at the heat pump units.

I would appreciate knowing anyone's experiences in this area.

[Joel Ashley]

Our old '85 Pace Arrow had 2 regular AC's.  To cut into the propane use of the furnace, around '88 I figured why not add a heat strip to one and take advantage of having electric as part of the park fees I was paying regardless of how much power we used.  The strip easily wired into the pocket behind a unit's filter, and the units already were pre-wired, with a "Heat Pump" setting on the dials.  The strip was okay, but nothing I'd totally depend on in really cold weather.

All that said, I'm not sure how a unit with one would work with our thermostats, given they don't have heat strip settings that I'm aware of, at least not on ours.  They do have heat pump settings however.  I'd guess the AC unit must have a switch on the inside escutcheon, but I don't know since the modern ones for big coaches are certainly designed differently than mine in 1985.  So whether a ready-made, separately-switched, heat-stripped unit jives without much trouble with a wall thermostat like ours, I can't say.  Perhaps certain models are designed to.

I just don't know why one would want a heat strip with a heat pump, which is why you see that they don't come from the factory that way.  Below 40 degrees the pump won't work, and a strip may work, but be nearly worthless.  Also consider that in coaches as big as ours are, with slide outs creating far more interior space to heat than our Pace Arrow had, a heat strip likely wouldn't have a lot of effect at any outside temp.

Joel

[Fred Brooks]

        Hi Bob,
    Is your thermostat a "5 button comfort control" ? If so, It will not work with the current new model replacement a/c's. Your choices are replace the t-stat with the new 9 button style and then change the pc board on the other air conditioner, or keep the 5 button and order a pc board along with your new air conditioner that works with the old thermostat. Call dometic tech support and do your homework. Keep in mind your other air conditioner is 11 -12 years old.
      Hope this helps, Fred
PS...Heat strip is an other word for electric heat element like found in portable electric heaters.

[Bob Bulot]

Thanks again for all the great comments!

Update:  I had a certified AC repairman out yesterday.  Turns out I need two new units.  He verified that the last owner had replaced the front-most unit.  As to the others, Someone had done a bad job attaching one of those refill ports to one of the bad units.  The adapter leaked all the refrigerant out, and also, there is oil leaking all over the place.  The other one has similar evidence of oil leakage around the compressor and has also lost most of its Freon.  The older I get, the more I find that I have to be careful of repairmen, but this guy earned my confidence. 

These units are 11 years old, so I'm going to err on the side of caution and replace them.  Just the thought of being anywhere near my Whacky Wife this summer in hot humid Florida, without AC,  is too horrific to contemplate

First issue:  This coach has heat pump units - no heat strips. So it is a cost/benefit analysis. The heat pump versions are each several hundred dollars more.   Keith highlights most of the benefits.  One additional benefit is that replacing the units with heat pump models retains the "equipment integrity" of the coach, come re-sale time.

The downsides as I see them are:

a. We don't do any extreme cold weather RV'ing (on purpose, that is).  An example of aforementioned W/Wife's idea of roughing it would be a black and white TV in the bedroom.
b. The good (front) unit is still a heat-pump unit.  It is on its own thermostat.  For light duty heating on shore/power, this would probably be sufficient.
c. I have had two other coaches with heat pumps, and have never had occasion to use them.

Gerald, I am reluctant to go to the Brisk Airs, especially when replacing only two of the three units.  Plus, I am concerned about the height difference.  At half the price of the Penguin II's, I am not sure the other differences.

As to the new-style thermostats, Fred, I will need at least one for the two new units, regardless.  I found them new on eBay for $60 each, so have ordered two of them.  If nothing else, they look to be infinitely easier to read.  No more cellphone flashlights.

Great discussion....

[Keith Moffett]

Hey Bob, just a FYI.  We were in Lordsburg NM last night and the night before.  Night time temps dropped to high 30's.  We didnt run the diesel heat.  We were dry camping and needed the generator so also used the heat pumps.  No need to burn extra diesel.

[Bob Bulot]

Hey Bob, just a FYI.  We were in Lordsburg NM last night and the night before.  Night time temps dropped to high 30's.  We didnt run the diesel heat.  We were dry camping and needed the generator so also used the heat pumps.  No need to burn extra diesel.

Good question: Which burns more diesel:  Generator running Aqua Hot electric heat? or generator running heat pump? Or Aqua Hot diesel?

[Joel Ashley]

I think you're looking at a half gallon an hour regardless.

[Fred Brooks]

      Hi Bob,
   If the coach came with 2 thermostats then proceed. Make sure that the technician that replaces the rear air conditioner that he "sets the dip switches" on the PC board to match the existing settings on the old air conditioner so aqua hot zones won't get messed up and center air (if equipped) gets lost. Love your sense of humor keeping your Sweetie happy!
       Regards, Fred

[Gerald Farris]

Bob,
Do your homework and get the replacement unit that fits your needs. All replacement A/C units have positive and negative features from height to cooling capacity, but on some units the extra cost feature is in reduced power consumption that may or may not be a benefit to you depending on who pays the light bill. I was just offering you an inexpensive option.

Gerald