As some thieving renter has AGAIN switched on pool heat (this time my CCTV got 'em!) I want to install 2 very simple relays to allow me to control the pump and the heater. I don’t need to monitor temperature or anything fancy because the pump is only single speed and the heater is getting on in years so I will at some point replace the lot by which time I hope someone has a decent ST compatible pool controller!
What I’m thinking is
Nutone NFS20Z which is only 20 Amps but can be wired as what appears to be called “dry contact wiring” in the USA (the contacts are open/closed but the main power supply powering the relay is not switched through to the contacts). This would allow me to use this relay to break the “call for heat” line to the heater which would prevent its use.
The pump is 30 Amps but the Aeon Labs ZW078-A will cope up to 40A so should be OK
While not advised by some, breaking one leg of a 240v circuit with a standard smart switch is possible and AFAIK not against code. I have my pump and heater controlled this way. Just another option…
That’s an interesting idea although I’m not sure what the contact ratings are. Obviously if a device is rated at 15Amp it assumes you are drawing 15 amps through the device. If you are only using it to break the circuit the rating of the switch is not important as long as the contacts can withstand the load being switched
I think I’ve found a way to Use a cheap Qubino D1 relay to switch my pool pump as it looks like there is a relay in the existing panel. My plan would be to break in at the point marked X - can anyone see a reason why that wouldn’t work as it’s only switching 24v at that point