Warm Salon in Miami Beach

[solanderi]

A plastic bag covered the AC raw water intake (when I moved the boat we saw it float away) and the AC stopped blowing cool air. The fan runs full blast but does not get cold. The stateroom AC works fine. How do I start to trouble shoot this problem ? Thank you,

Greg

 

[Genesis]

Does the compressor come on? If not, check and make sure the breaker is closed.

There are protective switches on the AC condensing (compressor) units that prevent it from burning up (or blowing up - literally!) if the cooling water is not flowing. These switches can fail when they activate, which will prevent the unit from restarting.

If you have digital controls, a trip on these switches usually requires a manual reset from the control panel. The old-style thermostats reset automatically.

 

[solanderi]

Thanks Karl,

The compressor does not kick on. Do you mean a breaker on the main panel in the salon or the fuses in the ER ? Do I need to access the AC unit itself?

 

[Genesis]

There is usually a breaker for each condensing unit on the main panel. There is not normally a separate set of fuses or breakers at the condensing units themselves.

Is this an "old-style" system with mechanical dials, the "Hatteras style" with mechanical thermostats, or an electronic controls systems?

 

[solanderi]

Definitely original and vintage.

 

[Genesis]

If its the "three dial" system (temperature, start/run, and fan speed) then if the compressor won't run it either has no power or the protective switch has failed open. If it has no power its either the breaker going to it, the trigger board, or the compressor itself has taken a dump.

There is a relay box that has little trigger boards in it. These LOVE to fail. I have a fix for this problem but it doesn't help you once they've pooped - you have to get a new one. I've also got some of the relays (which is what blows) and the correct value resistors (CruiseAir did a bad-bad with the design on these) as well.

 

[solanderi]

Thank you. I am going to the boat, hoping its a breaker. I have seen your posts regarding the relays and I hope I don't need to go down that road.

 

[solanderi]

Genesis,

I do have the above system that you refer to (auto, off, fan). When you say "protective switch", do you specifically mean a breaker on the board ? If not, how do I find it ?

 

[Genesis]

Genesis,

I do have the above system that you refer to (auto, off, fan). When you say "protective switch", do you specifically mean a breaker on the board ? If not, how do I find it ?

If you have the system with a thermostat and a three-position switch on the bottom, you have the same wiring I've got.

The thermostat is a line-voltage unit - BE CAREFUL - there is 220V on there! This is NOT a 24V thermostat!

The thermostat itself has two terminals which energize either heat or cool - basically, they control the reversing solenoid for heat, and energizing the system.

There is one trigger box for the water pump, and one for each compressor. All zones except one have time-delay resistors that present a time delay before they start so all compressors don't try to start at once (crude, but it works.)

The problem that FREQUENTLY comes up with these is that the trigger board design is really bad. The relay coil is overdriven and it burns out, which means the trigger doesn't, and the unit doesn't run.

If this happens in the pump relay box, then the pump doesn't come on with that zone and the unit will repeatedly trip off on high head. If it happens in the condensor relay box then the unit will not start at all.

The triggers are little boards inside the relay boxes. They are repairable if you can find the reed relays. I have a few of them, but not many. Cruisair is reputed to have a newer design that gets rid of all the silly stuff and is just a relay now.

If you work on this make damn sure ALL power is off to ALL parts of the AC system before you start opening things up.

If the breakers at the panel are not tripped and the unit will not start at all its a good bet the trigger has failed. If you pull one of the boards I can give you a test procedure using a VOM that will tell you what's up with it, or you can just swap the suspect trigger with a different one and see if the problem moves.

 

[solanderi]

Thanks Karl,

It was not the breakers,so I will move on to plan B. Thank you for your help as always,

Greg

 

[Genesis]

Its PROBABLY a trigger in the control box. The easiest way to test it is to swap a couple of them and see if the problem moves.

 

[captddis]

Hopefully it is the trigger, but I have seen the problem on others where the compressor keeps trying to restart until it cooks itself. If you have the digital controls ut will shutdown after a couple restarts, if you have the knobs it will keep trying. Good Luck.

 

[We'll See]

Beard Marine A/C in Ft lauderdale provides excellent service if needed. They supported my 26 y/o units until they went south and did a great new installation. I have them service mine whenever I'm in S FL.

 

[Pascal]

mines (ocean Breeze) have pressure switches on the condensing units that will pop if flow is interupted, preventing the compressor to start.

resetting is easy... just press the switch.

 

[Karl]

It is possible that due to the plastic covering up the water intake that the water pump lost its prime. This happened to me on my boat for a different reason and I had the same problem as you, but was fine after the prime was reestablished.

 

[solanderi]

Remember in my post that the stateroom AC is working fine. There is only one raw water pump for both units, right? So the pump not priming is probably not the problem, right ? Thank you for the help so far. I will likely involve a marine AC guy, and let the forum hear what he finds. Thank you for the "luck", I'll probably need it.

 

[Genesis]

Remember in my post that the stateroom AC is working fine. There is only one raw water pump for both units, right? So the pump not priming is probably not the problem, right ? Thank you for the help so far. I will likely involve a marine AC guy, and let the forum hear what he finds. Thank you for the "luck", I'll probably need it.

You're half-right.

There is a trigger relay box for the pump. It contains one board for each AC unit, and is responsible for running the pump when EITHER is on.

If that trigger is bad for the salon AC unit, the compressor will cycle on and off on high head UNLESS the stateroom AC is running. This is, again, a trigger problem.

But if the compressor NEVER starts (you CAN hear it come on) then the problem is not there, because if that trigger is dead the unit will start but won't stay running due to the lack of cooling water.

 

[Pascal]

it's really not rocket science... first check for water flow. since your SR AC works, it sounds like you have flow... then the problem has to come from the fact that your AC safety was triggered when a bag clogged the intake. I guess at that time the SR wasn't running and it didn't trigger.

you must have a safety switch on the condensing unit... don't know where they are on the cruisairs but it shoudl be easy to spot... that's all you have to reset.

beware of the AC guy attempting to throw parts at a problem that doens't exist....