Cruisair Problem

[leisha]

Hi, we have a cruisair self contained air conditioning unit on our boat. It was working fine. We did try it on the heat mode that i dint think its been on before. The unit is a 1990 vintage. The fans fun the start relay clicks but the compressor will not start. Occasionaly the compressor will start, works and then seems to get quieter and after 40-60 seconds the compressor stops. There are three knobs on the control panel, its recently been gasses and thats ok. would it be the start or run capacitor? I did remove them and they are showing open circit. We are currently in Barcelona and the temperature is 32 celcius with two small children aboard, any ideas?

[Captain Dad]

Check to make sure that water is flowing through the unit. Sounds to me like the water pump">raw water pump isn't putting water through the system and the compressor's high pressure safety switch is activating. We go through raw water pumps about every 2 years, but since we live in the Florida Keys the A/C is running for 6 months at a stretch.

when you turn the unit on and the relay (actually the thermostat) clicks, there should be water coming out of the discharge. If not, then you've found your problem.

Good Luck

[Sailmonkey]

A capacitor will read open after a short period of charging, you should see (with the meter set on the OHMS scale) a gradual increase in resistance until it's charged. To double check, discharge the caps with a screwdriver across both terminals and plug the meter in again. This will catch about 90% of bad caps, but I don't think these are your problem, probable more along the lines of the water flow, or even the heat/cool shuttle valve stuck between heat and cool. Try turning on the heat again, let it run for a minute, turn the unit off for 10 minutes, then switch on to cool.

[GordMay]

This document describes techniques for the testing of capacitors using a multimeter without a capacitance test mode:

http://www.repairfaq.org/sam/captest.htm