Hot Tubs

Hot Tubs:
Visited a house with one yesterday. I find it interesting that there are no power specs printed in the manual, like they’re hiding something. And then, when you hunt up EE recs for tubs, they’re hard to find.
One common statement from mfrs is “don’t turn them off.” Is this true? Smells untrue. And “it takes more energy to heat it from the start than it does to keep it hot.” Like what we were told about starting up our PCs.
This one’s on 24/7/365. Does anybody have a handy resource or remember a research paper or something? I found a handy usage calculator, in Britain, so I just need to convert pence to cents. My quick calc says this one’s costing about $100/mo to operate ($0.37/kWh here in Hawaii).

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  • I carry a watt meter with me.   tells me HZ  amps and volts and power factor.  If on a AC unit will tell how good of shape the cap is.   I have a redfish and fluke

  • thank you, Sean, Brennan...look what you get when you beg for it and when they begrudgingly give it to you they make it a point to tell you "we are only required to have these on CA tubs"7967087280?profile=RESIZE_930x

  • Sorry on the guide but yes that is accurate - don't turn the heat off or the filter. Usage betrween even the same unit can vary dramatically - where is it at (outside, inside, shady, city), do they leave it covered, temprature selected, how often is it used (i.e. jets / just taking cover off)

    The only true way to know usage is monitor it or extropalate based on labels on motors

    • I agree with Sean on this. Newer units should have an Energy Guide Label (see template here, which will estimate the annual usage in standby mode (i.e., temp set, lid closed, no jets, etc.). Obviously that will be a dramatic underestimate of usage, but its at least a baseline to compare between units. To reduce energy use, drop the temp by a degree or two. Also, for EE recommendations, you might consider a heat pump ( or solar spa heater (anywhere from DIY solar loop to a manufactured unit).  

      The Association of Pool & Spa Professionals > Hot Tubs/IHTA > Resources > Portable Electric Spa Ene…
      For more than half a century, APSP has been serving members and the public with critical industry knowledge that ranges from sound regulatory practic…
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