I have a 1978 35 Bertram.  The forward AC will not heat or cool.  First off I do have pretty good knowledge of the boat and it's systems.  I can't believe I can't figure this out.  It is a Cruisair split system.  The compressor sits under the cockpit on the port side.  The fan is behind the closet on the port side.  When you turn the unit on with the manual switches up front the pump turns on and the compressor sounds like it comes on.  When you try to adjust the air temp you get nothing.  Not hot and not cold.  The aft unit works perfectly.  Can you help?  Thanks in advance.

Post edited 7:30 am – May 16, 2011 by Steve Pooler

I'd like to help…But I need a bit more info  

You Say: "and the compressor sounds like it comes on"

Need to know if it does or doesn't because it won't heat or cool if it does not…To be sure it is running is the first step in troubleshooting this.

One way to tell if the compressor is running is to feel the water coil when you think it's running…In cooling, the water coil should have heat in it…In heat mode, the water coil should be cool…If you feel neither, then feel the smaller tube coming out of the compressor, but only touch it quickly at first because it can get very hot…

If that tube is only warm, the compressor is running, but it's likely you have either lost refrigerant, or your reversing valve may have stuck half way…But I'm getting too far ahead here…  

We need to be sure that the compressor is "In Fact" running before we get into the other possibilities…

Steve~

Steve,

       The smaller tubes coming off the compressor and the compressor itself get super hot, like burning hot.  There is water running through the system I checked that.  Being that it is a two part system, the coils over by the radiator and fan are super cold on the right side but nowhere else.  The radiator itself doesn't get hot or cold.  When you switch it from hot to cold with the switch it does make different noises but the air temp doesn't change.  Maybe it is out of refrigerant?  On the aft air conditioner one of the tubes coming off the unit to the seperate radiator gets cold and one gets warm.  On the forward one that doesn't work neither changes temp.  Thanks so much for your help.

Matt