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Vitodens for Spa

Paul Pollets
Paul Pollets Member Posts: 3,427
You need to know the gallon capacity of the spa (presuming it uses a pool filter, and is not a bathtub) and the distance from the spa to the boiler system. Usually the piping is done in either copper or CPVC from the FPHX to the pool filter. We use a Tekmar 150 setpoint control to set the spa temps. Pipe sizing is dependent upon BTU requirements and flow rates.

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  • Ricopp
    Ricopp Member Posts: 25
    Spa heater

    I've got an ongoing job with an indoor hot tub that the pool guys forgot to inform me that they are not responsible for heating the water. (So now I am) The question is can a Vitodens 100 be used for the heat source? I'm not sure what the flow rate is on the hot tub circ. (maybe someone knows what is typical). The requirements of the tub are approx 80,000 BTUH.The electrician has a spare conduit (11/2") so I can't get 2 - 3/4" pex line through, from the existing boiler in the basement (can 3/4" even accommodate 80,000 btu?)
    Thanks in advance - RO
  • tim smith
    tim smith Member Posts: 2,397
    Yes, use a plate and frame or shell & tube heat x

    then you will just bypass water from main pump to vitodens, basically primary/secondary arrangement. Will work just fin. May be a little slow to heat up but will work.
  • And don't forget...

    to use a titanium heat exchanger if there is ANY sodium in the water. Otherwise, your HXer will swiss cheese on you in about 2 years :-)

  • Glen
    Glen Member Posts: 855
    and -

    you can use the external call for heat function (output from the 150 ) to ramp up the vito for faster recovery. May be used with a timed relay to minimize loss of heat to home.
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