Cruisair A/C Tripping Breaker

[Houseboat_Livin]

Originally Posted by Cadence

I know nothing about the smxII tripping a breaker. Is the voltage reading under load. Is it feasible the new dock side unit is being tripped by the smxII because of line lose in the connecting dock cable. Just a thought.

I'm not ruling it out, but it seems to be powering everything else just fine. Even the mini fridge and water heater, which provide a sizeable amperage draw and they all share the same ground strip. I feel like i would see the issues in other areas as well if it were a cable issue, but I'm not ruling it out. No excess corrosion or oxidation on the cable terminals either, fyi.

[Houseboat_Livin]

Originally Posted by Squanderbucks

I remember just reading a couple of months ago about many people experiencing similar problems with many of the new or "upgraded" marina electrical systems. Do a search on the Motor and Power Yachts magazine and see what turns up.
Essentially new electrical standards are much less forgiving of wiring issues on boats and many boats are now having similar problems when they did not before. Something to do with grounding procedures changing over the years.
Apparently they said that if that is the issue it can take a circuit by circuit diagnosis to find the fault.
Turn everything off, plug in only shore power cord and test. then turn on main breaker box with all individual circuits off and each individual power user unplugged, then one by one turn the breakers and the devices on each circuit in a row, on till breaker trips. Keep going till device or circuit is found.

Yea I saw a similar article. I've been doing exactly that. I plan on continuing that process tonight. I have already ruled out the compressor and water pump, but with it being such an immediate trip of the gfci, it has me believing it is one of those components I haven't physically disconnected yet. There are only so many things that it could be. Removing the fan and capacitors from the circuit individually are going to be my starting point tonight. If none of those prove to be it then I'm going try disconnecting the pressure switches, evap sensor and control display. If none of those provide any answers then I'm going to recommend a control/logic board.

[Houseboat_Livin]

Originally Posted by ebs001

It's pretty certain you have a ground fault. You can confirm this by plugging the boat into a non GFCI outlet and turning on the breaker. A GFCI trips at less than 5 milliamps leak to ground which is never going to trip a regular breaker. Once you removed the power logic controller it didn't trip which sounds like it would be the culprit of the ground fault. Moving to another pedestal will not change a thing.

My first step would be to reinstall the logic controller and try the breaker again just to confirm that it is causing the problem. Make sure that the controller is isolated. That is only power connected to it, black white and green. If the problem persists then the controller will have to be replaced. If not connect the other wires. You'll need the schematic to know what you are connecting so that you can isolate the other components to see which one is tripping the GFCI. It could also be in the wiring harness. With such little tolerance that GFCI's have it doesn't take much to make them trip so it can be very tricky to track down a ground fault.

Great info! The schematic is glued under the power in cover, so I can identify. This process is similar to what i was going to try, but you're right. If I disconnect everything except for the power into the logic board, it will help me rule that out more quickly.

[Houseboat_Livin]

Originally Posted by ebs001

It's pretty certain you have a ground fault. You can confirm this by plugging the boat into a non GFCI outlet and turning on the breaker. A GFCI trips at less than 5 milliamps leak to ground which is never going to trip a regular breaker. Once you removed the power logic controller it didn't trip which sounds like it would be the culprit of the ground fault. Moving to another pedestal will not change a thing.

My first step would be to reinstall the logic controller and try the breaker again just to confirm that it is causing the problem. Make sure that the controller is isolated. That is only power connected to it, black white and green. If the problem persists then the controller will have to be replaced. If not connect the other wires. You'll need the schematic to know what you are connecting so that you can isolate the other components to see which one is tripping the GFCI. It could also be in the wiring harness. With such little tolerance that GFCI's have it doesn't take much to make them trip so it can be very tricky to track down a ground fault.

Great info! The schematic is glued under the power in cover, so I can identify. This process is similar to what i was going to try, but you're right. If I disconnect everything except for the power into the logic board, it will help me rule that out more quickly.

[Houseboat_Livin]

Originally Posted by ebs001

It's pretty certain you have a ground fault. You can confirm this by plugging the boat into a non GFCI outlet and turning on the breaker. A GFCI trips at less than 5 milliamps leak to ground which is never going to trip a regular breaker. Once you removed the power logic controller it didn't trip which sounds like it would be the culprit of the ground fault. Moving to another pedestal will not change a thing.

My first step would be to reinstall the logic controller and try the breaker again just to confirm that it is causing the problem. Make sure that the controller is isolated. That is only power connected to it, black white and green. If the problem persists then the controller will have to be replaced. If not connect the other wires. You'll need the schematic to know what you are connecting so that you can isolate the other components to see which one is tripping the GFCI. It could also be in the wiring harness. With such little tolerance that GFCI's have it doesn't take much to make them trip so it can be very tricky to track down a ground fault.

Update: I disconnected everything from the controller board EXCEPT for the power to run the board itself. The gfci breaker tripped! I disconnect the power from the board, the gfci breaker does not trip. Just for fun I ran a separate ground directly from the board to the boat breakers ground strip and the gfci breaker still tripped. I ordered a new board and it'll be here Monday. If for some reason it's still tripping the breaker, which would be my luck, can you think of anything else I am missing? Thanks for all of your help!

[US1Fountain]

Have you tried turning on several AC items that are on a different CB, such as battery charger and a couple of 120V lights, with the Air Conditioner breaker off, and then plugged in the shorepower?

[Houseboat_Livin]

Update: installed new board. Issue still present. 😭 I have gotten to the point where literally everything is completely isolated from the circuit except power to the new board. Nothing is even connected to the distribution terminals, its literally just power to the board and its still tripping the marina breaker. Either I got another bad board or the marina is the problem. Everything else on the boats AC circuit turns on just fine. Turn on the a/c breaker and it trips the marina breaker. I'm about to run an extension cord from my boat to the sailboat and see if that works. If it does then I'm going to wire in a gfci outlet and run power off of that, I don't think it's going to work though. Any ideas?

[US1Fountain]

Post 21. As I asked before, have you tried having other current draws (ceramic heater) switched on, before you actually plug in the shore cord?

[Houseboat_Livin]

Update: WE'VE GOT POWER! Improperly connected neutral at the boat breaker was causing it. I've got power to the display, the fan is blowing, everything sounds good. Turn it to cool, relay clicks once, a few seconds pass, compressor attempts to turn on, marina breaker trips. I disconnected the compressor from the circuit and it runs fine. Relay just keeps clicking, trying to turn the compressor on, but doesn't trip the breaker. I'm leaning towards the compressor being shorted, but maybe there's a small chance it could be the capacitors. Input appreciated!

[Houseboat_Livin]

Originally Posted by US1Fountain

Post 21. As I asked before, have you tried having other current draws (ceramic heater) switched on, before you actually plug in the shore cord?

Everything else runs fine. No matter when it's plugged in. The system is running now, just tripping marina breaker when compressor attempts to turn on. Unplug compressor and relay clicks, but no trip. I'm leaning towards shorted compressor. What do you think?

[US1Fountain]

HVAC guy I’m not. Maybe the start up amps too high, otherwise I’ll defer to the more knowledgeable. Good to hear you are getting there. But to double check, on your initial post you stated everything worked fine until the marina rewire. Is that to say the AC unit worked fine then too?

[Houseboat_Livin]

Originally Posted by US1Fountain

HVAC guy I’m not. Maybe the start up amps too high, otherwise I’ll defer to the more knowledgeable. Good to hear you are getting there. But to double check, on your initial post you stated everything worked fine until the marina rewire. Is that to say the AC unit worked fine then too?

I'm quoting what the owner told me. He stated it worked fine prior, but I believe he said the last time he ran it was this past spring. It's also 20 plus years old.

[KeelMe]

Originally Posted by Houseboat_Livin

Bump, let me know if you have any questions.

What is my wife making for dinner tonight? I'll be back at the boat soon and don't want to call but I'd really like to know.

[J.Kitchens]

Find an electrician.

An electrician could diagnose that thing in minutes.

I shouldn't have to tell you electricity is dangerous.

[KeelMe]

Originally Posted by J.Kitchens

Find an electrician.

An electrician could diagnose that thing in minutes.

I shouldn't have to tell you electricity is dangerous.

Jason is right. I only skimmed the thread but it seems you are unqualified.

Tell the owner to quit being cheap. You have to pay to play the game. If you make a mistake, your medical bills will cost a lot more than paying a qualified electrician.