I am seeking advice on how to run power for a second ac unit on a 2023 Heartland Trail Runner 27RKS. The trailer has 50amp hookup, it doesn't seem to have been pre wired for another ac. I also do not know what the labeling means in the breaker panel. Any advice would be greatly appreciated.
Power for second ac unit
- Thread starter Shoe1963
- Start date
If you have 50 Amp service then there is a good chance that you are wired for a second AC. Your breaker panel appears to have a breaker for a second AC.
If you have a 14x14 vent in the ceiling of the bedroom you will need to remove the inside shroud and look for a piece of romex cable, probably terminated in a plastic box.
If you find that you should be good to go on installing a forward AC.
Peace
Dave
If you have a 14x14 vent in the ceiling of the bedroom you will need to remove the inside shroud and look for a piece of romex cable, probably terminated in a plastic box.
If you find that you should be good to go on installing a forward AC.
Peace
Dave
wdk450
Well-known member
I noted that the breaker labelled "AC1" is a 20 amp breaker, where the breaker labelled "AC2" is a 15 amp breaker. Both AC units are usually identical, so would need the same size breakers. Also, air conditioning breakers are a special HACR type, with a longer delay before tripping.
HACR (Heating/Air Conditioning/Refrigeration) rating — It can handle a brief surge in amperage that's required for a compressor or other devices to start.
Both air conditioners should NOT be both connected to the same feed phase to balance the electrical loading. On my breaker box, the 2 phases feed every other breaker. That is, looking at the breakers left to right you have phase A, B, A, B, A, B and so forth .
HACR (Heating/Air Conditioning/Refrigeration) rating — It can handle a brief surge in amperage that's required for a compressor or other devices to start.
Both air conditioners should NOT be both connected to the same feed phase to balance the electrical loading. On my breaker box, the 2 phases feed every other breaker. That is, looking at the breakers left to right you have phase A, B, A, B, A, B and so forth .
jerryjay11
Well-known member
If so, then the 20-amp breaker appears to have the microwave on it. Got the feeling that at least the first 4 breakers are mislabeled. And aren't RV AC units typically 115 volts? I do realize some may be 240 volts, but most are 115V from my experience.
SeanMacGerailt
Member
Good info here. I am also planning to add a second AC unit, to my garage. I haven't pulled the vent fan yet to verify the power wire is there, but like the OP showed, I have a 50 amp setup, and a "2nd AC" breaker, so I expect it is there.
Question is, when adding the 2nd unit, what is typically done for a thermostat for on/off and temp setting? Could control it on the unit itself, but since the ceiling is pretty high, a wall mount would be better. I can, of course, run a wire, just wondering if that pre-wire that as well.
The main unit in the living area has one of those Dometic t-stats that I'm not in love with. Tried to replace it with a Honeywell, but it appears they designed it so you're stuck with theirs.
Question is, when adding the 2nd unit, what is typically done for a thermostat for on/off and temp setting? Could control it on the unit itself, but since the ceiling is pretty high, a wall mount would be better. I can, of course, run a wire, just wondering if that pre-wire that as well.
The main unit in the living area has one of those Dometic t-stats that I'm not in love with. Tried to replace it with a Honeywell, but it appears they designed it so you're stuck with theirs.
jerryjay11
Well-known member
What makes you stuck with the Dometic?
If not mistaken, a T-Stat is a T-Stat. As long as you replace with a same number wire T-Stat and follow the instructions to install it. Just count the number of wires, noting the color codes for wiring the new one.
If not mistaken, a T-Stat is a T-Stat. As long as you replace with a same number wire T-Stat and follow the instructions to install it. Just count the number of wires, noting the color codes for wiring the new one.
jerryjay11
Well-known member
I was under the impression t-stat had to be 12-volt DC or battery powered. That's according to an article I read. I'll have to dig deeper. Never had to replace one so I may need some studying just in case.
SeanMacGerailt
Member
Correct, this is the issue. These apparently have some form of communication to the unit. Not the simple switching of a call for AC or heat like the typical t-stat. My issue with the Dometic is that it allows too much temperature swing. I have resolved this on other RV's by swapping to a Honeywell digital t-stat that keeps the deadband tighter. Could not find any info in the manual or online about settings for this on the Dometic.
Anyone have thoughts on my original question?
SeanMacGerailt
Member
Update: So this weekend, I got up in the ceiling of the garage to look for the power wiring for the 2nd AC. Pulled the fan shroud down and looked around with a flashlight. Went elbow deep everywhere I could reach, above and below the insulation. Only found DC wiring for the fan, and cables going back to the lights for the outside rear of the trailer. Also pulled a light fixture and speaker in the garage and found no signs of the AC power wire or a box it might be terminated in. Even opened a chase in the garage cabinets where the power is fed to the receptacles.
Then I opened the breaker panel. There is definitely a yellow jacketed romex cable connected to the 20 amp breaker marked "R. AC". It appears to go up the chase behind the control panel, as I can see from the basement.
Next, I shut off all breakers except "R. AC", and checked for anything powered in the whole RV. Could find no power in any outlet, appliance, etc. This indicates the circuit is not being used to power something else, best I can tell.
The original dealer documents I got with the RV show that it included "wired and framed for 2nd A/C" as standard equipment.
Am I missing something obvious? Where would they have run the wire to? The vent opening area is the only place that seems logical to me.
Then I opened the breaker panel. There is definitely a yellow jacketed romex cable connected to the 20 amp breaker marked "R. AC". It appears to go up the chase behind the control panel, as I can see from the basement.
Next, I shut off all breakers except "R. AC", and checked for anything powered in the whole RV. Could find no power in any outlet, appliance, etc. This indicates the circuit is not being used to power something else, best I can tell.
The original dealer documents I got with the RV show that it included "wired and framed for 2nd A/C" as standard equipment.
Am I missing something obvious? Where would they have run the wire to? The vent opening area is the only place that seems logical to me.
Dennyha
Well-known member
As you did before, shut off breakers to everything but the rear AC. Then use a NCVT to search the ceiling in the garage, looking for signs of voltage. Good Luck
SeanMacGerailt
Member
Thanks, good suggestion. I have a NCVT, just had not thought of trying it, thinking it wouldn't sense well enough through the ceiling plywood. But yeah, it might with all other sources off!
david-steph2018
Well-known member
In an earlier post, you said the "main AC is in the living area". Is there an AC unit in the bedroom?
If not, I would suggest checking the bedroom area for the cable. Lot of time when people add an AC unit it is in the bedroom area.
So, if there is a vent in the bedroom, that may be where the cable is ran for the 2nd AC. "R.AC" could mean "Reserve AC".
wdk450
Well-known member
You might try a wire tracing kit (available at most home improvement stores). This puts a radio signal on the wires (this is probably done best with all the power shut off, the romex disconnected from the breaker, and the transmitter connection made there) and a variable sensitivity receiver to trace the wiring.. You might be able to rent such a kit from the tool rental section of most home improvement stores.
Have you called Heartland Service to answer where the power wire end for the 2nd air conditioner might be found? Have your VIN at the ready.
Have you called Heartland Service to answer where the power wire end for the 2nd air conditioner might be found? Have your VIN at the ready.
SeanMacGerailt
Member
Thank you for the replies. I tried the NCVT Monday and wasn't able to pick up voltage through the wall or ceiling. Got to thinking about what exactly they mean by front vs rear AC. I had been thinking of the AC unit in my living room/kitchen as the front unit, and the rear would mean the garage. Nope. Found the front AC wire in the front bedroom vent, so the rear is the living room/kitchen unit. So, good input, david-steph2018! By the way, the front vent has a blank termination (basically looks like a receptacle with no outlet). This makes it super apparent where the AC pre-wiring is, and it is live with the F AC breaker on. Unfortunately, it does me no good. The bedroom is cooled just fine with existing AC unit in the living area, while my garage does not get sufficient cooling through the one ceiling vent. I use it as my office when working remotely, and it got pretty hot in there last summer. Had to use a fan blowing from the living area into the garage to help, but it simply needs it's own AC unit.
Now that I know this, my plan is to fish a wire from the garage cabinet receptacle up through the ceiling to the garage vent and add a 13K BTU unit. I have fairly decent access in the cabinet, and the speaker opening in the ceiling. The 13K unit should be fine on the 15 amp circuit, as the only other things I'll have plugged in is my laptop and monitors.
Now that I know this, my plan is to fish a wire from the garage cabinet receptacle up through the ceiling to the garage vent and add a 13K BTU unit. I have fairly decent access in the cabinet, and the speaker opening in the ceiling. The 13K unit should be fine on the 15 amp circuit, as the only other things I'll have plugged in is my laptop and monitors.
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