I'm a newbie in the market for a pool with a spill over spa.  I'm thinking of heating the two with a heat pump but I'm getting conflicting advice from the pool contractors.  Some are saying I can use the heat pump to heat the spa and others are saying we shouldn't go that route.  The concern is that I won't be able to heat the spa in a reasonable amount of time (say 1 hour). I live on Long Island and I'd like to be able to extend the time I use the spa from April through October so as you can imagine the water temp of the spa, when cold, will have to come up considerably during those times, when I want to heat it. 

Does anyone have any experience when using a heat pump to heat a spa?  I loved to hear.
Marcus Miller

Thank you for writing to me. You can e-mail some people at this link to see their experiences with heat pumps for spas. http://poolheatpumps.com/customer_response.htm

Heat pumps are designed to go to 104 degrees as are gas heaters. A 110,000 BTU heat pump should heat a 500 gallon spa about 18 degrees and hour. A 400,000 BTU gas heater has about  330,000 BTU's because it loses 20 plus % up the exhaust. So a big gas heater will heat 3 X as fast. Most pools in the summer that are heated are at 84 degrees. So to get up to 102 would take an hour with a big heat pump. I always use heat pump with spas unless the spa are really big and the owner does not like to wait around or they want to jump in when it is 40 degrees outside.
Sincerely, Asa Strong
 Newbie using the heater.  Newly purchased home, with new Hayward 400 electronic gas heater.  Pool,(appr 16,000 gal) w/spillover spa (appr 300 gal)

 To use the spa only, I have the spa return-off, and the spa suction-off, with the spa motor, for the jets, turned-on. 

How do I get the spa to heat up? 

Does the heat come from the spa jets, or the spa return line?  

I felt heat coming from the spa return line, but I didn't want to damage the unit.

Thanks in advance, again I am a newbie in regards to using the pool heater.
Marcus Miller
Thank you for writing. Most overflow pool / spa combinations with one filter and water pump, send water to the spa jets and pull water from the pool during the day. Then when you want to use the spa, you change (2) 3 ways valves to pull water from the spa drain and send water to the jets stopping the overflow to only heat the spa. For every 100,000 BTU's of heat, you will get about an 18 degree temperature rise for every 500 gallons in the spa per hour. I would get with a local pool guy to go over everything as there are so many ways to pipe these things that we don't want to turn a wrong valve and drain the spa or the pool. It is depressing when you have a high water table and you drain the pool and it "pops" out of the ground.

Asa Strong
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