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Adding Dedicated Immersion Heater Element
Vaillant AroTherm ASHP with VRC 700 controller. We have the cheap overnight tariff (5hours). During the winter the system works best if heating is separated from DHW. Therefore I time the UFH and upstairs to operate during the low tariff schedule. The DHW is timed to operate during the dearer period.
I am thinking of replacing the current immersion with the T-smart immersion and run it independently (i.e during the low tariff). At present the wiring to the immersion is obviously controlled and operated by the VRC700.
My question, what will be the outcome if a) an electrician disconnects the wiring into the immersion (currently supplied by VRC700) and replaces with dedicated immersion spur to operate the T-smart or b) he connects both cables (doubles up) thereby having a dual supply to the immersion (although only the T smart will actually be used. I don’t want to purchase the T-smart if this is a non starter, i.e could throw the VRC 700 into fault mode or something else.
Our DHW is normally 39deg and heated to 50 deg so the T-smart should, I assume easily cope with the temp increase during the 5 hours and of course the Legionella run.
Thanks.
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