AC not working, just clicking

dcaffrey

The AC unit in my 342 will not start up but worked great 5 days ago.  The thermostat blinks dots seven times and then the unit under the V-berth clicks twice and then the seven blinks and two clicks and so on and so on.  This happens while on shore power and when on generator as well.  Has anyone seen this before or have an idea what might be happening? 

TonyG13

How old is the unit? Letting us know the approximate age, make, and model of your unit will help with troubleshooting. Most modern Dometic units have digital displays with letters and/or numerals to indicate fault settings. Picture of the thermostat will also help.

Dream_Inn

I've seen something very similar when I wasn't supplying correct power, the unit would keep cycling.  But for me it was ok on shore power.  I had to change some settings on my generator and then it worked fine.  I would not think you'd have that with both shore and generator.

YYZRC

Does the March pump kick on and water flows out the thru hull? If not, start there (system lost prime, clogged strainer or worst case bad pump). 

If the pump is working fine, I would replace the capacitor. Relatively inexpensive and DIY. 

dcaffrey

It's a 2016.  
The display only blinks several dots like periods seven times at a time. 
I have another midship shore power connection available that I never used, but I will try that on Friday so I can rule that out.  I got the boat last fall and the ac/heat worked great until now on genny and shore power.
Here's a photo of the ac info and back of the display.  I can get a pic of the display on Friday.
Where would I get a capacitor?

PickleRick

The last capacitor I purchased was Amazon.  Removed the old capacitor to get the numbers off of it.   Your local electrical supply or HVAC supply may also have it.  

MH342

If it helps, this should be the manual for that unit. 

dcaffrey

Thanks guys for your input.  The capacitor looked good and the problem ended up being a bad thermostat/controller.  The AC guy thought that it might be the cable, but I already ruled that out with another temporary cable.  We just plugged a new controller in and it works great.

PickleRick

Very nice. Glad it wasn't the capacitor.  Just replaced the capacitor on my heat pump and managed to shock myself 3 or 4 times in the process.  A thermostat replacement is much less painful. 

raybo3

@PickleRick How the heII did you shock yourself putting in a cap? Power off and a new cap should be discharged. If the cap had a charge just short it our with a screwdriver...... Just say'n

PickleRick

95 degrees outside working between the house and ac unit in the dark.  Power was off and I thought I had discharged it.   Apparently, I had not.   It was discharged by the time I was done with removal