A 32amp hot tub and a 40amp sauna on a regular, domestic 80amp supply

[marcuswareham]

If it is worked out and there is a problem with demand, then maybe a priority switching unit could be used like this:

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www.garo.ie

these switch off one of the loads if the priority load is taking more current

 

[telectrix]

first option is the best.
you'd think the 13A would cost less to run but that's wrong. the 32A option will draw more current, but will be heating for less time. basically you need to put in the same amount of electrical energy in both cases. just saying.
[automerge]1593594978[/automerge]

If it is worked out and there is a problem with demand, then maybe a priority switching unit could be used like this:

Search Results

www.garo.ie

these switch off one of the loads if the priority load is taking more current

see post #2. .

 

[marcuswareham]

first option is the best.
you'd think the 13A would cost less to run but that's wrong. the 32A option will draw more current, but will be heating for less time. basically you need to put in the same amount of electrical energy in both cases. just saying.
[automerge]1593594978[/automerge]

see post #2. .

Doh, sorry I thought you meant a manual change over switch

 

[Huejones]

Thanks all. Telectrix, I realised there’d be no energy saving, the 13a will just take longer getting up to temperature, I guess the extra pumps will use more energy on the 32a but you do get benefit from this extra energy. With the priority switch, does this automatically knock one thing off when another is switched on or do you operate it manually? Also, if I used a priority switch, could both items be connected to the same supply on the same rcd? Also, are these switches expensive? I’m minded to consider this further tbh and I guess it would be no problem to switch the sauna off to jump in the tub for 20 mins and then back. Both would probably retain sufficient heat between uses.
Thanks again.

 

[7029 dave]

Those priority boards look just the job.
Today's electrical accessories have come along way over the decades.