Re: Air conditioner seawater pump won’t start

Beaute Olivier

Hello Dean,

first, did you try to turn the pump shaft manually (thanks to a flat screw driver at the backside of the pump, where the fan is located)?
After several months of non use, the bronze impeller may be a bit frozen.

I confirm the pump starts as soon as you turn on the A/C on cooling mode. Then, depending on the boat's inside temperature, the compressor will start or not (can you hear the click of the thermostat when you turn it to low temp?).

The A/C pump is indeed started from three relays (one for each A/C unit). These relays are located in a grey box located at the aft portside of the engine room, close to the Shore/Generator automatic switch box.

Did you try to turn on all the A/Cs?

Good luck.


On Friday, August 30, 2019, 07:44:13 PM GMT+2, SY STELLA <stella@...> wrote:

Hi gang,
I just fired up my AC (not used at all this year!), because I want to make sure I can put antifreeze through the system.   My Calpeda seawater pump is not running, and I’m wondering why? ...

1. I’m measuring 240V at both ACTIVE AND NEUTRAL TERMINALS with reference to ground, but zero bolts between the ACTIVE and NEUTRAL. 
Seems like one terminal is being driven and the other is showing up through the winding, but is not being connected at the pump controller. Relay not activated? 

2. Is it just too cold for it to start. The ambient temp is lower than the lowest temp I can set the AC to, so I maybe the system won’t even try to start the pump?

if that’s the case, does anyone know how to fill the system into starting the pump so I can put Antifreeze into the lines?

Alternatively maybe the pump should always run, and there is a different problem ??  Anytime I’ve fired up my aircon in the past, the ambient temp has been high and I’m 90% sure the seawater pump starts immediately.

Would appreciate any guidance!

many thanks
SY Stella

Join to automatically receive all group messages.