Issues with Marvair System

[Tuennerman]

I'm wondering if anyone out there has experienced a similar issue with their Marvair Reverse Cycle Air Conditioners.

I have two (2), 16,000 BTUH Systems installed on my Catalina 445. According to Marvair's own Documentation, each System requires a minimum water flow of 282 GPH for a total of 564 GPH. The Systems were installed, one forward and one aft, with a single Cal Pump, installed midship.

I've been having a lot of problems, some of which I believe are related to Water Flow. Unfortunately, Marvair has not been responsive at all even though these Systems were installed six months ago.

1. Has anyone come across a similar configuration installed onboard their Vessel?
2. Has anyone had issues with their Marvair Systems maintaining temperature?
3. Has anyone had repeated Pump failures?

[BeautifulDay]

I have been chartering a 20011 Catalina 445 and I just purchased a used 2010 Catalina 445. The boat I have been chartering has had repeated problems with the A/C. (High Pressure kicks the unit off) This has caused me some concern about the boat I recently purchased. (I do not take delivery on the 2010 until 8/15/11 as the boat has to be trucked from the Great Lakes to Florida.) Here is what I can tell you about the problem:

At first we thought that Florida's hot climate and more than usual grass in the Gulf was clogging the filter. The intake fresh water intake filter/strainer sure seemed awfully small to be doing double duty. I also questioned the use of one pump for two systems. However, I have been told that this is a common set up.

My understanding is that the Catalina warranty has covered three different service calls. All different a/c refrigeration repair companies. As I write this email, none of the company's have been successful in fixing the problem. The owner of boat I have been chartering figured he would correct the problem through a modification to the system. He changed out the strainer/filter to a large Groco ARG-750-P water strainer. He also installed a Spectra Bio-Guard water treatment antifouling model BG-100 inline to retard marine growth. It was so impressive that I purchased the parts for the Catalina I purchased. However, shortly after the install, (and after I purchased the Groco & Spectra parts,) I went to use the charter Catalina this weekend and the saloon was in excess of 100 degrees. A small amount of water in the bilge had actually become stagnant from the malfunctioning A/C to the point it had clogged the intake of the bilge pump. I checked the Groco water strainer and it was clean!

Needless to say, the owner is very frustrated. I am wondering if I have just inherited this same problem the both of you are facing. I am beginning to suspect the system needs to be retrofitted with two seacock intakes, individual strainers and individual pumps. (the single pump and 3/4 inch single intake may not be enough to do the job.)

I plan on calling a contact at the Catalina factory on Monday to see if he has any insight. If you have corrected your A/C issue since posting on SailNet, your input would be greatly appreciated.

Thank!