I had the hot water running all good until we had a local power outage. I noted since the outage that I would only get warm or cold water if I have only one tap/shower on hot. The hot water would only come after you turn on a second tap/shower in the house. Once the hot water came through, I can turn the second tap/shower off and the water will remain on hot. If both taps are off and we needed hot water in an hour, I had to had two on again.

All taps are cold/hot mixed onse. I have turned the water cyliner on and off a few times byt that doesn't fix the problem. There was a leaking at the swatch to the cyliner which has been fixed but it didn't solve the hot water problem. I have had plumbers around for other jobs and none figgured out what was the deal with this one but all said it shouldn't have anything to do with the outage...

Anyone have any clue as what this problem is and how to fix it?

with many thanks