I have a Keston C55 it has been nothing but trouble for the last 2 years. We cannot have the central heating and hot water on at the same time, as the priority always goes to the hot water and not the underfloor heating, so we have to have them on a different times for either of them to work properly. We also have constant issues with all sorts of strange codes which appear on the boiler's read out panel. Most of the codes don't even appear in their manual so we have no idea what the boiler is doing most of the time. We often have C74 flashing on and off, D51 and other random codes. It often comes up with error codes that are in the book, the usual E codes, when the boiler is reset it settles down.
Our most recent issue is that it decides some days to turn the hot water on and on other days it just doesn't bother. There is no pattern to it, some times it happens in the morning, so we have cold showers, nice! On other occasions it doesn't come on in the evening, it follows no pattern and is entirely random. We have so far had 5 different time switches fitted as our electrician thought it was something to do with them, but the most recent clock is still making no difference.
We also use a huge amount of gas, as the boiler seems to keep 'ramping' itself up and down all the time. We have a 5 bed house, with 3 bathrooms, underfloor heating and there are three of us in the house, we use around £450 of gas every quarter - apart from the summer which is still about £300 a quarter.
Any one got any ideas what C74 means and D51? And what the issue is with not being able to have the hot water and central heating on at the same time. And why we have the random issue with the hot water not coming on.
This boiler really is a total piece of junk! It was expensive and was fitted because we needed to put it a basement with the flue being well above ground level, and our Plumber thought this was the only boiler that would work in that situation - so we are stuck with it.
Thanks Ruth.
