03-24-2022, 09:22 AM
I think you have the Dometic units, which are a type of mini split.
The most common failure is the outside fan stops working, the compressor head pressure goes high, and the breaker trips. So, first of all, confirm the outside fan is working.
If it is working, then locate the compressor wiring either at the outside unit, or inside the silver control box mounted on the inside unit. It is oddly shaped and usually secured with a large rubber strap. Inside that control box you will see a circuit board, and one of the relays on the circuit board will have wires coming out of the top of it. In either place, hang an ammeter on the wiring and report what it does.
1. Goes to locked rotor amperage right away, and breaker trips
2. Spikes, compressor starts and amperage slowly climbs until breaker trips
3. Something else
If it is not the outside condenser fan, than it could be as simple as the start capacitor on the compressor, or something more sinister like a fried compressor.
While you are nosing around in the silver control box, a number of owners including me, have found the twist on connectors where the power is fed into the control box have worked loose over the years and caused a poor connection. When I had a coach with that AC system, I found two almost fires where the connection had heated to the point of melting the insulation pretty far down the wire. I personally would go ahead and modify those connections using Alumaconn connectors. I am a big fan of bulletproofing the high amperage wire connections. Not cheap, but oh so robust. https://www.amazon.com/King-Safety-95104...132&sr=8-6
I think you are an electrical contractor, so you may have even better solutions.
The most common failure is the outside fan stops working, the compressor head pressure goes high, and the breaker trips. So, first of all, confirm the outside fan is working.
If it is working, then locate the compressor wiring either at the outside unit, or inside the silver control box mounted on the inside unit. It is oddly shaped and usually secured with a large rubber strap. Inside that control box you will see a circuit board, and one of the relays on the circuit board will have wires coming out of the top of it. In either place, hang an ammeter on the wiring and report what it does.
1. Goes to locked rotor amperage right away, and breaker trips
2. Spikes, compressor starts and amperage slowly climbs until breaker trips
3. Something else
If it is not the outside condenser fan, than it could be as simple as the start capacitor on the compressor, or something more sinister like a fried compressor.
While you are nosing around in the silver control box, a number of owners including me, have found the twist on connectors where the power is fed into the control box have worked loose over the years and caused a poor connection. When I had a coach with that AC system, I found two almost fires where the connection had heated to the point of melting the insulation pretty far down the wire. I personally would go ahead and modify those connections using Alumaconn connectors. I am a big fan of bulletproofing the high amperage wire connections. Not cheap, but oh so robust. https://www.amazon.com/King-Safety-95104...132&sr=8-6
I think you are an electrical contractor, so you may have even better solutions.
Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home
)