Air Conditioner Pump not working

[Rocky Lou]

When I switch on the Relay Switch and AFT/Forward AC switches, the AC pump does not come on. Also, after running a while, without raw water pumping, I get an E3 error code. There are a number of posts stating that I should prime the pump as a first step. My boat is always in water and the sea cock is always open, so I don't know how it would lose prime, but, I very rarely use it. In any case, I have a diagram of the system and would like to understand better how I use a garden hose to prime the pump and whether this requires two people as one post suggests. There may also be other steps to consider first before priming the pump?

 

[sgeary]

I would suggest: 1) making sure the a/c sea strainer is clear and 2) that the a/c thru hull is reopened after checking the strainer. If this does not solve the problem, on our boat the a/c pump has four thumb screws. I loosen three of the screws a few turns and then have someone turn on the a/c. As soon as the pump turns on, I loosen the fourth screw and the air will quickly be purged from the pump. Re-tighten the 4th screw quickly and then re-tighten the other three. This process has always worked for me.