Air conditioning raw water circulation pump won't start

[amber jj]

I replaced our 16k marine air air conditioner and thermostat with a Webasto fcf16000 in February while on the hard. Pretty much a nobrainer wiring and duct work was already there. I just had to run wire for the new thermostat and reinstall wiring from the panel and raw water pump.
When we launched the first of June and tried the air the raw water pump would not start. I took the hot wire from the pump and jumped it to the hot terminal on the circuit board. The pump worked instantly.
When I turn the unit on at the thermostat the fan starts up and after 30 seconds or so the twenty amp breaker kicks out. I don't know if it's the compressor kicking in or not.
I am sure my wiring is correct. I think there may be a problem in the circuit board or a relay switch.
I will call Webasto Monday. I tried techwebsto and got a invalid address message.
Any thoughts would be appreciated.
Thanks Bob

[catalina_mike]

Is it something you have to program in the display? Not sure of that unit.. Just throwing it out there. Is there a jumper that has to be installed on the board?

[amber jj]

I checked and double checked the installation instructions and didn't see anything like that.The old marine air when you turned it on the pump started right away.I am assuming most units do the same.

[catalina_mike]

Actualy several manufactures can have a single pump for multiple ac units. They need to be configured in some cases. But it should be in the manual so if it's not that way on yours not sure.

[Pitou]

When we launched the first of June and tried the air the raw water pump would not start. I took the hot wire from the pump and jumped it to the hot terminal on the circuit board. The pump worked instantly.
When I turn the unit on at the thermostat the fan starts up and after 30 seconds or so the twenty amp breaker kicks out. I don't know if it's the compressor kicking in or not.

Just a thought ... When you jumped the pump to hot, did you confirm that you were pumping raw water throughout the air conditioning system and out the thru hull? If not you need to break the line coming into the pump and prime the system from your raw water intake.

[drbob]

Similar situation. I thought the pump wasn't running when in fact, it was running, but running almost silently dry. 20 seconds, kicks off. We've had to bleed the pump before it would kick in and push water. It only runs when the system needs to be cooled down. After I bleed the pump, life is good and the air is chilled.

Bob DeGroot
2005 A28TE Box, Gen & AC
www.CapeHarbour.com

[amber jj]

When I did jump the hot wire from the pump I did a visual check and it was pump raw water.

[amber jj]

I just called Webasto tech and they said first of all check the fuse on the circuit board,if blows again I may need a 120v.20amp. relay switch.He suggested may just be drawing to much current.
Now I have to wait to the weekend or take the 120 mile drive to try the fuse.