Chosen Solution
I have a Rinnai RL94 Tankless hot water heater. It’s not clear to me from the owner’s manual whether the unit needs to be descaled regularly, or whether it’s all right to wait for one of the corresponding “LC” warning codes to appear. I know this depends on the hardness of my local water supply. Is this something that I would be doing pre-emptively, or is it all right to just wait for the warning?
Hi @jbclements , I don’t know the answer but I suppose that you can pre-empt the problem from occurring by occasionally flushing the system as described on p.15 of the manual, to help prolong the life of the heat exchanger. Perhaps you could check with your local water supply authority as to the hardness of the water in your area to give you some idea of how often this may be required. Maybe check how quickly the scale builds up in a kitchen electric kettle, just to have some idea of the water quality. Also on p.14 of the manual it describes how to view the fault history so that you can check if an 00 code is there or not.