Do I need a 20 amp thermostat?

stumac · Nov 12, 2023

I have bought an old house in rural France and it has an oil tank and Unical oil powered boiler (Italian I think). Its a beast of a thing but can't find any model info or any plates on it.

I want to change the switch and thermostat to a digital wireless thermostat but I'm not sure what I can replace it with. The switch is a 20a switch which is separate to the thermostat which is a pretty regular mechanical thermostat (see attached).

I assume if I want to combine the switch and thermostat in a single control unit it will need to be rated at 20a... But struggling to find any and many advertised with amp rating...

Have emailed Unical dealer near me and Unical HQ but no reply.... Can anyone give me any advice...

ShaunCorbs · Nov 13, 2023

No 3-5amp thermostat

You sure the switch doesn’t hold fuses ?

stumac · Nov 13, 2023

Hi @ShaunCorbs

The two little black things on the switch are x2 10amp fuses....

Do I not need to wire the switch and the thermostat to the same controller?

Gasmk1 · Nov 13, 2023

Surely that’s just an old isolator

stumac · Nov 14, 2023

Found this sticker on the inside of the existing mechanical thermostat, so I guess I should replace with a 10a or is that overkill? I'll re locate the idolater to beside the boiler... @Gasmk1 @ShaunCorbs

ShaunCorbs · Nov 14, 2023

I would say overkill but nothing wrong in going bigger if you can find one and it’s price acceptable

You could run it through a contactor then you could use a 1 amp version etc

Basher · Nov 15, 2023

There seem to be many smart thermostats now with 16A contact rating, typically designed for electric ufh, but would be fine for this.

Just a thought - you could if you wanted put an RF receiver near the boiler, and then put an RF (battery powered) smart stat wherever you wanted in the house.
eg 16A Wireless Electric Heating Receiver - RF Switch 16A - https://heatmisershop.co.uk/16a-wireless-electric-heating-receiver-rf-switch-16a/