WaterNet Online

Hello all,

I have a 20,000 gal swimming pool with hot tub. It has been running about 5 years and has never worked quite right. My system includes a Hayward Northstar 2hp motor that runs the pool and spa combo. In the loop I have a De72 filter, Aquacal heat pump and Hayward h400 gas heater and Jandy Aquapure salt system. Controlling the whole think is Jandy automation. Normally the system draws from the main drain and skimmers and returns to pool returns and spa bubbler. When I activate spa mode 3 Jandy valves pull from the spa, water is sent through the gas heater instead of heat pump, and returned to spa jets. I also have a Hayward 1 hp for a waterfall. Pressure in the de filter is 20psi and I change powder at 30 psi.

The problem is that when I pull from 2 of 3 sources(main drain and skimmer or main drain and spa) the system works fine. When I go to one source(the spa is the worst) the pump slowly loses the prime and the pump is only about half full with water. It makes the spa unusable and the gas usage huge. If I can overcome this problem my wife and kids would be very happy!

The spa is plumbed with 2" pvc about 100 feet away from the pump and includes about 15 elbows. It has 5 jets.

A few questions:

1. I have been told that the pump is way overkill and I should change it. The recomendation is to go to 1hp 2 speed. Would that be enough? Good recomendation or is variable speed better?

2. I believe the plumbing run is too long and the pvc is too small. If I go t a 2.5 or even 3" and remove the elbows will it help. I can get down to 90 feet with 4 elbows. I can get to within 2 feet of the spa drains and jump to the bigger pipe and run it to the equipment. If I increase the size of the suction pipe, do I need to increase the return to the jets also?  Can a pump be expected to run effeciently that far even with 3" pipe? I have 5 spa jets. Then what size pump should I get?

3. Since I believe the plumbing needs changing is there a better manner to plumb a pool/spa/waterfall combination?

4. I presently have a Jandy actuator that either feeds the heat pump or gas heater depending on whether I am in spa mode.Is it a good idea to run the heat pump and gas heater in series to increase efficiency of the heating(I would use the Jandy actuator as a bypass when they are not in use).

5. I wonder if I should use 1 pump(perhaps variable speed or 2 speed for pool/spa bubbler/waterfall) and 2nd pump for spa jets?

I wish the system was designed properly in the first place but now need to reengineer. Moving all the equipment is the one issue that I really cannot change(about 90 feet run to the spa, and 30 feet to the pool). But the plumbing in the ground, pumps, and layout is all on the table. Thank you in advance for any help, advice or guidance.

Regards,
Useless hot tub