Air Conditioner mystery

I have two Marine Air Systems units. The forward unit is 7K and functions perfectly. The stern unit is 16K also functions perfectly, except when I start it up. After a few seconds the digital control gives an HHH code. I shut it wait 2-3 minutes, start again and it will run all day. It will cycle on and off as the temperature settings require and function perfectly. It runs cold,and cycles. If I turn the unit off and then back on it is fine. Both units run off the same raw water pump and the filter basket is clean. The mystery unit is a split unit model CSP-16K..
I have spoken to their tech service dept. They think it is a wire issue but I don't see how a wire would fix it self when you turn it on a second time.
I thought it might be the high pressure switch, but if it cycles and runs continuously after the initial try I would think that the high pressure switch is functioning.
I would appreciate some help
Thanks

High head pressure on first start-up, check voltage (low voltage not uncommon in marinas). Check wire connections including at the breaker for good clean connections.

If the unit is getting old the initial start requirements may be more then the compressor can do until it's run some to "loosen" things up a bit. Installing a start capacitor (hard start kit) may help.


Regards,

Might want to start looking at the relay box next, possibly by cycling it the contacts make a better connection, I'd measure (volt) the line going to the compressor, before start 0 vac, then when thermostat is called in should read 120vac. Do you have a manual with the wiring schematic, if not maybe manufacture could email you that page?
Just a thought off the top of my head, I'm not an A/C expert by no means.

Thanks for the quick reply
Boat at my home dock and voltage is ok
I will check the breaker for any corrosion
However I have never heard of a hard start kit capacitor
Would this be a Marine Air Systems product?

Did some research on hard start kit
Seems very logical
I will try and let you know

oak said:

Boat at my home dock and voltage is ok

Click to expand...

You need to check the voltage under load and specifically under the load of the AC when starting. Connect your meter (an analog meter will work best for this) and have someone start the unit. Look for a short term voltage drop. Do this at the power pedestal first and if you don't see a voltage drop, connect the meter to the power leads at the AC unit and repeat the test. If you now see a voltage drop, the problem is with the shorepower cord or connectors or the boat's wiring.

Since wire won't get smaller on it's own, the problem would be with one or more connections in the circuit.

The air flow over the condenser isn't blocked or restricted in any way is it?

Have you tried switching control panels?

The air flow over condenser is clear. The bow unit starts with no problem.
When I get a second hand I will check the voltages, if not an issue
I will look into switching the bow control to the stern

Get a hard start relay. Two wire hookup to start cap. Will give start cap and comp a good starting voltage if low and is better when the unit short cycles. Check any a/c ,appliance repair shop,or granger. Also see if wires are cooked at relay ,comp ,or cap.