I have a Remeha Avanta 39c combi which is 8 years old and I have to say has worked brilliantly and has not given us any trouble.
However, last week I noticed that the upstairs basin tap and the shower would get hot for about 2 minutes and then go cold. When I came downstairs to check the boiler, I noticed that it had stopped providing the DHW and was in standby mode - no errors showing. Downstairs taps are working fine - it just seems to be upstairs where the pressure is slightly lower.
I've taken the secondary heat plate exchanger out and cleaned it with acetic acid - it was pretty clean anyway, no gunge or anything like that, just a little bit of limescale build up, but only a bit.
I also took out the 3 way valve and gave that a good clean, checked the seals, replaced it and checked it is operating smoothly.
The only thing I've noticed is that the flow sensor doesn't light up unless the downstairs taps are almost fully open, but never having needed to check it out before, I'm not sure whether that's normal or not.
The shower is a thermostatic mixer type and the basin tap is a mono-block. I also think the upstairs pressure may have reduced, but only slightly.
After cleaning the heat plate exchanger I've noticed that the water gets hotter quicker, but the problem with the upstairs DHW is still concurring. The central heating side is working fine.
Does anyone have any ideas as to what may be causing this? I'm thinking maybe the flow sensor is faulty?
However, last week I noticed that the upstairs basin tap and the shower would get hot for about 2 minutes and then go cold. When I came downstairs to check the boiler, I noticed that it had stopped providing the DHW and was in standby mode - no errors showing. Downstairs taps are working fine - it just seems to be upstairs where the pressure is slightly lower.
I've taken the secondary heat plate exchanger out and cleaned it with acetic acid - it was pretty clean anyway, no gunge or anything like that, just a little bit of limescale build up, but only a bit.
I also took out the 3 way valve and gave that a good clean, checked the seals, replaced it and checked it is operating smoothly.
The only thing I've noticed is that the flow sensor doesn't light up unless the downstairs taps are almost fully open, but never having needed to check it out before, I'm not sure whether that's normal or not.
The shower is a thermostatic mixer type and the basin tap is a mono-block. I also think the upstairs pressure may have reduced, but only slightly.
After cleaning the heat plate exchanger I've noticed that the water gets hotter quicker, but the problem with the upstairs DHW is still concurring. The central heating side is working fine.
Does anyone have any ideas as to what may be causing this? I'm thinking maybe the flow sensor is faulty?
