Messed Up The A/C

bduncan1231

bduncan1231

Member
Feb 3, 2009
62
Mount Juliet, TN
Boat Info
93 500 Sundancer
02 Active Thunder 37 Excess
Engines
Detroit 6V92's
555’s N/A 680hp each
Well, I thought I had a genset problem and jumped downstairs to shut it off. I checked everything over and didnt have a problem (thought there wasnt enough water flow) so I started it back up. Now here's the problem, I didnt shut any of the panel switches off downstairs including all A/C switches. Everything powered back up except the A/C. All my A/C panels are blank and the pump is not starting. I checked voltage to the pump and with the pump relay switch on I have 218 volts to the pump. If I fried the pump would it keep the panels from lighting up or have I done a lot of damage? I was hoping maybe there is a relay or circuit breaker somewhere for idiots like me but I have yet to find one. Any suggestions? Thanks for any input
 
Not sure but this should not cause you any problems?!? These marine systems are made for a lot of abuse and various power up and down scenarios. Our slip neighbor nver shuts the breakers off, just turns the genny off and flips the main switches and then plugs in shoer power and the ac fires right back up.

I wonder if you prob is something else??
 
I dont know I hope it is something simple. I sent an email to Marine Air Systems hope to hear back from them tomorrow
 
Since you have power to the pump, but nothing to the armature nor to the control panels, you may have several problems. Start one by one.

The Circuit Breaker could have been fried, with shore power off, check continuity of the breaker in the on position. No continuity replace the breaker and test. Breaker OK? Go to the control panel for the AC typically hidden somewhere. With power off open and check for broken burnt wires or burnt out trigger(s). In the AC control box there are triggers that could have been blown, check continuity and replace as necessary. All OK look for in line fuses to the temperature and fan controls, replace any fuses blown, All Okay, go to pump and check for a burnt armature causing the moror to sieze to a burnt spot. Armature burnt, remove and try to clean before replacing pump motor.

Good luck:

Fou you and others her eis a "Best Practice" for power handing:

Alwasy trun of poer to ships systems and equipemnt at the breaker and do it one breaker at a time beginning with the lightest loads first, Establish a rountine ans train everyone on board how to turn off power. Your last load to take out would be the biggest 220Load, the AC compressors and then finally the pump,. When switching to Shore or Genset, do as discussed above and abck on in exact reverse. Make this a habit. Never have all your loads running and just hit the mains off and on, this can blow stuff all over in older the boats with increased resistances.

Good luck
 
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The cooling pump and the a/c units are on different breakers on most boats. The switches on your main panel are really switch duty breakers. When the power came back up, there was a tremendous starting load put on the system by the compressors trying to start up at the same time. If I were betting, I'd bet that you tripped the breakers on the panel.....try turning them to the off position them back on to reset them. If this is the case, the water pump would show voltage but it woud not be triggered by the Marine Air units to come on.
 
fwebster said:
The cooling pump and the a/c units are on different breakers on most boats. The switches on your main panel are really switch duty breakers. When the power came back up, there was a tremendous starting load put on the system by the compressors trying to start up at the same time. If I were betting, I'd bet that you tripped the breakers on the panel.....try turning them to the off position them back on to reset them. If this is the case, the water pump would show voltage but it woud not be triggered by the Marine Air units to come on.
Click to expand...

Frank. I have never found seprate breakers for cooling pump and ac unit on my 340DA ... where would they be??
 
You wouldn't have a separate breaker for the pump unless you have multiple air conditioners served by a single pump (pump relay box).
 
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Doesn't 218 VAC sound a little low for a circuit that should have 240?
 
Well, I went down this afternoon and hit the A/C switches with the shore power on and everything started working just fine. So, I fired up the generator, powered everything down and switched over to generator power, powered up everything and the A/C controls will not come on. Switched back to shorepower and everything (A/C) is working fine so what gives? Everything works on shorepower or generator except the A/C. Thanks again
 
My memory is not the greatest, but I swear there was a post on here several months ago with similar symptoms - A/C ok on shore power, but not on generator. Seems they eventually found a problem with a switch on the genny? I could be totally wrong, but you might try a search.
 
Its leading to that. I have never shut the genset off from the panel on the genset. I had a similar problem on our 390 but it wasnt A/C related. That is the first thing I'm checking tomorrow and working back from there. Frank, if you are out there, it looks like that 390 is headed to PC around October, looking forward to meeting you
 
Brad,

Just a heads up...........one of the challenges with a boat in Florida is insurance. Nobody will bind coverage for a Fla cruising area during hurricane season with storms anywhere out there. Pick a time when there are no storms and get insurance coverage before you need it.

I'm not hard to find....come by Treasure Island or look for a 450DA with an aft enclosure. We use the boat nearly very day we are in town.
 
My boat is all 115v, so this is just a W.A.G. from an idiot, but is it possible you've lost one "leg" of output from the gen so you're only getting 115v to your panel and not 230v that might be needed for the a/c units?
 
Yeah, my panel is reading 223 volts and 20 to 25 amps which is normal for the load I usually have on it. I'm going down tomorrow to check everything. Thanks for the info Frank. I'm heading down this weekend to work on the house for a week and probably wont be back until october. I'll look you up when we get down there. Thanks again all.
 
There was a post a while ago exactly like this. I believe it turned out to be the governor on the generator was the issue? It did not regulate the voltage properly/quickly enough, so when the A/C unit initially started it did not have enough voltage to start or was under frequency and that caused the A/C unit to not kick on... But it worked fine on shorepower. Sounds like that may be the case given that 218 V reading that was posted before...
 
Hi. You have now confirmed that the AC is fine. By the way, the voltage is 120 volt on all boats, except European models. For some reason, the power isn't getting from the genny to that breaker...different panel?, as I have 2, and not sure about yours. If all is fine, measure voltage at the Ac with shorepower, and then repeat with genny on...should be the same. I not, maybe the genny is putting out the wrong voltage, and the AC is reading that, and protecting itself. Good luck.
 
400ec man said:
Hi. You have now confirmed that the AC is fine. By the way, the voltage is 120 volt on all boats, except European models. For some reason, the power isn't getting from the genny to that breaker...different panel?, as I have 2, and not sure about yours. If all is fine, measure voltage at the Ac with shorepower, and then repeat with genny on...should be the same. I not, maybe the genny is putting out the wrong voltage, and the AC is reading that, and protecting itself. Good luck.
Click to expand...

Dude, you're just flat out wrong.
Larger yachts have 50 amp, 230v shore power and often, the larger motors/compressors- the air conditioning systems- will be 230v as it is more efficient.
 
Sorry dude, thought we were talking about a 390, not a 500 and 240V is obviously correct.
 
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