Three A/C Rig Question

Captcolour

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Verona, KY
Our 2021 Solitude 380FL has 3 A/C units. The A/C in the kitchen area keeps tripping its 15 amp breaker. This A/C unit is also a heat pump. The A/C's in the living area and bedroom are both standard A/C units and are on 20 amp circuits. Is this correct that the kitchen A/C would only be a 15 amp circuit, or is the breaker wrong? A/C runs for about a minute before it trips.
 
If the kitchen AC is a 15K BTU unit, it should be on a 20A breaker. You would need to verify that the wiring is #12 before increasing the breaker size as #14 wire is only rated for 15A. It's possible the wrong breaker was installed at the factory.
If the AC is a 13.5BTU and tripping a 15A breaker, then you have a problem elsewhere.
 
I agree, at first that does sound like it may be on too small of a breaker. Maybe you could install a Micro-Air Soft-Start system so that it uses less energy to get the compressor going, which could resolve your issues with the breaker blowing after a minute and it would also help the system last longer since it no longer Jolts the compressor into a working phase. That's just my thoughts. I've installed one of them in each of our 2 rooftop Coleman's for longevity reasons, and the ability to be on 30amp if necessary. They're a very easy item to install, and it gets you into your AC system so that you can see what cleaning it will be like in the future during routine maintenance.
 
Looked at the build sheet and all 3 A/C's are in fact 15K BTUs. I'll call GD customer service to see if they can verify by the serial number whether it should be 20 amp or 15 amp before doing anything myself.
 
You will get a better result by calling Airxcel tech support.
You can drop the grill inside and somewhere up in the unit there should be a manufacturers data sticker giving all of the specs on the unit.
 
You will get a better result by calling Airxcel tech support.
You can drop the grill inside and somewhere up in the unit there should be a manufacturers data sticker giving all of the specs on the unit.
Since it is tripping a 15 amp breaker, it is a really safe bet that it is indeed a 15K unit as it is suppossed to be.
Likely has the wrong breaker installed. As was already said, do NOT put a 20 amp breaker in if it does not have 12GA wire... It is possible they also installed the wrong wire as well. This is a real simple thing to check. With the unit unplugged, just remove the breaker box cover so you can see the wires. Since you do have 20 amp circuits, you have something to compare it to. If the 15 amp wire is the same as the 20 amp wires.... 5.00 for a new breaker , 5 minutes with a screwdiver and you will be all fixed up. If the wire size is too small, then get Grand Design involved
 
Just FYI - All my AC units (1 15k & 2 13.5k) have 20 amp breakers. As mentioned above, look in your panel and verify wire size but they are probably all the same. You should be able to just change the breaker.
 
Update 07/16/21

Had a chance to pull the breaker panel and the wire to the breaker is only 14 ga. So just increasing to a 20 amp breaker isn't an option. Put a service request in for the National Rally.
 
Update 12/25/21

At the national rally back in August, service techs were stumped that the unit was wired from the factory with 14 ga wire and a 15 amp breaker.

Rig is currently in for a list of warranty work and the A/C was on the list. Turns out the unit is bad and they are replacing the A/C under warranty. Since new units come with a soft start, wonder if this replacement will have that already. Hope so.
 
A 15KBTU unit requires a 20A breaker and 12ga wire. You can not just replace a breaker with one of a higher amp rating to eliminate nuisance trips. To do so is asking for a fire and a denial of an insurance claim. The breaker is there to protect the wire, not the device.
 
A 15KBTU unit requires a 20A breaker and 12ga wire. You can not just replace a breaker with one of a higher amp rating to eliminate nuisance trips. To do so is asking for a fire and a denial of an insurance claim. The breaker is there to protect the wire, not the device.

Yes and verified as reported above that the wires are definitely 14 ga so breaker has to remain 15 amps. If the new A/C unit they are installing under warranty comes with the soft-start, then the 15amp circuit may work just fine. If the new A/C unit doesn't fix the problem, then I will push to have the wiring upgraded to 12 ga and a 20 amp breaker installed.
 
*Update* Just got the rig back from warranty work. They had to replace the AC/heat pump unit. Ran it for awhile when I got home and works fine on the 15 amp circuit. The new unit may have a soft start on it as it didn't seem to just blast on. Hopefully problem solved for the long term.
 
The new unit is at risk of failure. It may seem to run OK, but you are getting a voltage drop over the 14 ga wire and extended running on low voltage will damage the compressor. These units do not have the electronics to sense a low voltage condition and will continue running.
 
The new unit is at risk of failure. It may seem to run OK, but you are getting a voltage drop over the 14 ga wire and extended running on low voltage will damage the compressor. These units do not have the electronics to sense a low voltage condition and will continue running.

Nonsense, a voltage drop would not occur unless the unit attempted to draw more than 15 amps. In that case, the 15 amp breaker would trip, as it is designed to do. The unit cannot be pulling more than 15 amps because of the breaker, therefore, 14 gauge wire is sufficient.
 
Nonsense, a voltage drop would not occur unless the unit attempted to draw more than 15 amps. In that case, the 15 amp breaker would trip, as it is designed to do. The unit cannot be pulling more than 15 amps because of the breaker, therefore, 14 gauge wire is sufficient.

This may be just a bit more complicated. Circuits are designed to serve 80% of the rated capacity continuously. A 15 amp circuit shouldn't serve higher than a 12 amp load. The extra 20% is for starting currents, short term peaks, and safety margin. If Captcolour has Coleman-Mach 15 PS units in his 380FL (as we have in our 2021 380FL) they have a full load rating (continuous) of 11.8 amps on high fan, so you should be OK. However, you mentioned that this is a heat pump unit with heating capability. Under heating load, that unit is rated at 15.6 amps, well in excess of 12 amps and higher than the 15 amp breaker.

Have you tried the new unit with the heater yet? Grand Design should have put a 12 gauge wire and a 20 amp breaker on that circuit.
 
I've attached an excerpt from Airxcel's installation manual for Series 48xxx model RV air conditioners. It's clear this should be a 20 amp circuit.

Airxcel Install manual.png
 
This may be just a bit more complicated. Circuits are designed to serve 80% of the rated capacity continuously. A 15 amp circuit shouldn't serve higher than a 12 amp load. The extra 20% is for starting currents, short term peaks, and safety margin. If Captcolour has Coleman-Mach 15 PS units in his 380FL (as we have in our 2021 380FL) they have a full load rating (continuous) of 11.8 amps on high fan, so you should be OK. However, you mentioned that this is a heat pump unit with heating capability. Under heating load, that unit is rated at 15.6 amps, well in excess of 12 amps and higher than the 15 amp breaker.

Have you tried the new unit with the heater yet? Grand Design should have put a 12 gauge wire and a 20 amp breaker on that circuit.

This is just a heat pump (compressor only) without the option supplemental heater. So the 16 amps is not required for this unit. The original unit worked fine when operated as a heat pump. Never tripped the breaker and provided typical heat pump quality heat. Running the A/C would trip the breaker. I did not try the heat pump yet but don't expect it to be a problem.

As I said, if we start having problems again, then I will push GD to rewire to 12 ga and a 20 amp breaker. They replaced the unit under warranty so will see how it does.
 

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