I am finishing off someone else’s job, there were controlled from a phone using Lightwave immersion heater switches on both the peak and off peak supplies that the other guy took out for some unknown reason, now they need to be reinstalled.


Apparently the off peak Lightwave switch was only supplied by the off peak CU, but I am told it worked.


I am weighing up the possibilities:

• The switch has a rechargeable battery and works when the power is off.

• The app stores the command and executes it when the switch is powered up overnight.

• The switch doesn’t work, but the customer doesn’t realise this as he is not at home when the switch is supposed to turn the off peak immersion heater off.

I am thinking the switch needs a permanent supply.