Unrecommended
I have had a bad experience with a !2,000 Btu. Polar BAy unit on my recent (Oct. 2003) B311. Everything was okay until the waters of MObile Bay heated up to 88 to 90 Degrees F. this summer. Despite assurances from the manufacturer that this unit SHOULD be adequate for this size boat, in FACT it is NOT! The unit loses the ability to keep the temperature between 72 and 74 degrees F. about 9:30 a.m. until 7:30 p.m. with the maximum inside temperature rising to 88 degrees F. There is a bimini and dodger combination over the cockpit. Putting reflective, R6.4 foam over the skylight and hatches cuts the maximum temperature to 85 degrees F. Unfortunately the 16,000 Btu. unit won't fit under the sink, so what's a fellow to do? Belatedly I find that the formulas for sizing the units in the Defender and Boat U.S. catalogs, if carefully followed to estimate the volume to be cooled, give what appear to be a better answer, 15,500 Btu. Three different sets of gauges have been on the unit, in one case with the president of the Polar BAy company on the phone getting the readings simultaneously. He insists the unit is working properly, and that it is sized right; but he cannot explain why the unit won't keep me COOL. I am a Registered Professional Engineer (Retired) and an Emeritus Professor of Engineering at the University of Alabama in Huntsville. My thermodynamics background is from the U. S. Naval Academy. I have satisfactorily supervised and installed several Air Conditioning units ranging from home units to central office units.
