My combined (not combi) gas HW+CH system has been working with no problems then suddenly, last week, the "hot" water coming out of the shower and all taps is barely warm. The gas boiler and the programmer lights are on.
It seems that the HW is being partly heated but not anything like hot enough, compared to how it normally is.
I have not touched the surface mounted HW-cylinder stat so it is still set at 65c.
The CH radiators are all nicely warm.
When I turn the HW switch OFF at the CH/HW programmer, I hear a sound like the m/v is operating and I can feel the pipes either side of the HW m/v are very hot.
When the gas boiler is on, the HW cylinder now does not feel hot at all but tonight, when I turned on the electric (back-up) water immersion heater, I got hot water in the shower and taps within 20 minutes.
It seems that the HW is being partly heated but not anything like hot enough, compared to how it normally is.
I have not touched the surface mounted HW-cylinder stat so it is still set at 65c.
The CH radiators are all nicely warm.
When I turn the HW switch OFF at the CH/HW programmer, I hear a sound like the m/v is operating and I can feel the pipes either side of the HW m/v are very hot.
When the gas boiler is on, the HW cylinder now does not feel hot at all but tonight, when I turned on the electric (back-up) water immersion heater, I got hot water in the shower and taps within 20 minutes.