Post edited 12:32 pm – August 18, 2010 by Steve Pooler

Peter~

The process of changing a compressor on a self contained unit is usually something like…

Due to space restrictions for making solder joints…

• The complete unit is removed from the boat & put on a bench for access.
• The old compressor tubing is either cut out, or the solder joints are heated & separated.
• The compressor is then unbolted, wires removed, and lifted out of the unit.
• New compressor is lowered into that space, and if different, extra tubing may need to be cut & bent to adapt to the existing.
• They may also need to adapt the mounting due to the new type compressor.
• Solder joints are made with a torch.
• Wires are connected.
• Vacuum pump is connected & the system is evacuated.
• Freon is either measured in by weight on the high side as a liquid (no need to run the unit) or the unit is bottle pressure charged (vapor) then started & run with a garden hose, the charge is then balanced while running the unit…This also verifies if the compressor is a good match (since the type was changed)
• Unit is leak tested while out of the boat to insure none of the new, or old joints are leaking freon which would cause the new compressor to fail.
• Reinstall the complete unit & test for proper operation…Of course if the boat is out of the water you can't do this to get an accurate test of where it lives conditions to see if there was/is a problem with the original installation…Maybe one that could have caused the first compressor to go bad.

With compressor pricing nowdays between $600 to $700…$1200 for a compressor change is not uncommon…You see the labor & extras involved.

I personally have not changed a compressor for quite some time because when I describe all this, plus the fact that they still end up with a older unit with almost (if any) no warranty, plus the fact that $1200 is half way to a new unit with 2 year warranty…Most folks opt for the new unit which is likely an improvement over the older model too (size, weight, performance, etc.)

In your case I would say call a qualified guy out to check it…But I'm not sure if you will find a person in Canada (Not much Marine A/C work up there) that has enough experience under his belt to deal with the different compressor install…Even if he does get it running is he going to know if it performs as well as the original would, and if it is a good enough match to last ?…Unmatched flow rates from old to new can show in operating pressures, and can cause premature failure along with other problems such as icing, or flood back of liquid to the compressor.

There has been $1200 spent on this unit…Another compressor may cost that much again…$2400 will surely buy that new unit with factory warranty (actually less than $2400 retail & I discount units)

Here is a link to a servicing dealer locator http://www.dometicenviro.com/d…..hp?l=water  You might give that a shot to see if one is near the boat…

Steve~