Jon Claerbout
899 Allardice Way
Stanford, CA 94305
650-493-1393 & 650-723-3717
June 20, 2007

Dave, Tom, and Ron Allen
Allen's Pool Refinishing
2366 Pruneridge Avenue
Santa Clara, CA 95050
(408) 984-6737


Subject:     Need help!   Please reply!

Dear Dave, Tom, and Ron,

You will recall a $10,000 job you did for me this past winter -- refinish and new filter canister with large area. Immediately following your installation I had a problem that I to not understand. I need your help. Please respond to my telephone messages, or this letter.

The first time after your work that I used the hot tub I noticed a squeal coming from the motor area. I cannot localize it. I thought, "Shucks, sounds like a filter motor bearing." With more experience I am coming to a different opinion; but I am absolutely baffled. The pool has a cover on it, so it is only recently that I had occasion to clean up by sweeping the bottom. The story gets much stranger! First I noticed the problem arises only when the spa water is above about 90 degrees! Then I noticed the bizarre pressure behavior. Normally the pressure runs about 11 lbs on pool and 15 lbs on spa. When the water reaches about 90 degrees, there is a clicking sound, and then within about 30 seconds the pressure rises to 28 lbs(!) and the whistling begins. I believe the whistle is not a motor bearing for this reason: When I turn off the pumps, they stop about instantly, but the squeal dies out over 5 sec or so as the pressure drops. Also, your installation provided a device I had not seen before -- a check valve with a clear plastic lid showing a spring-loaded flap inside. As I'm heating the spa past 90 degrees, when the click happens and the pressure jumps, I can see the flap partially close.

What am I to guess? You are the experts. I'm not at all confident in any of my guesses. Perhaps some temperature-sensitive plastic has worked its way to the pump impeller? I did find the pump filter basket after your installation full of fiberglass bits. I can't imagine any temperature sensitive blockage in my old heater or your new filter. I'm stuck.

I'm sorry to hear that Tom is out with a medical problem. I hope you'll understand that I do require communication with you.

Sincerely,

Jon Claerbout (650) 493-1393