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PROBLEMS WITH MIXER TAP, SHOWER RUNS HOT THEN FREEZING COLD
Anonymous user 01/03/2024 - 2.53 PM
I have a combi boiler Potterton Performa HE. A few months ago my mixer tap on my old Victorian style shower mixer stopped working, where the taps would work fine, but as soon as I used the mixer for the shower, the hot water would cut out. But if I switched it back to taps, the hot water would come through fine. And at the same time my boiler was losing pressure regularly. My boiler cover company replaced the pressure sensor valve in the boiler and i had a plumber replace the mixer tap for a thermostatic mixer. The boiler continued to lose pressure and the shower continued to only run initially hot then freezing cold (but work absolutely fine on taps without the mixer being used) I had numerous call outs to the boiler, and was advised I must have a leak under my floorboards downstairs as there was 'nothing wrong' with the boiler. I also took advice from a plumber who advised thermostatic mixers shouldn't be used with combi boilers. I refused to believe I had a leak to got the boiler people out again, and finally had an engineer who noticed the heat exchanger had split. And at the same time I replaced the thermostatic shower mixer with a new shower mixer with ceramic disk technology as advised. On 28/12/2015 The heat exchanger was fitted and I already had the new mixer tap installed. After the engineer left, all was well. The boiler maintained pressure, and my shower worked properly for the first time in months and stayed warm. This was still the case every time I the shower was used since. Until.... As it was relatively warm, I had the heating off. The next morning, I ran the shower and the water would not heat up. I checked the boiler and the burner was not igniting when hot taps were ran. As soon as I turned the heating on, the hot water started to flow and the shower worked great. I called an engineer out who could only come out 4 days later, during which time, the problem remained. On the day the engineer came out, the problem had rectified. He checked everything for me including the diverter valve but could find no fault. Hot water ran fine without the heating on when he was there. And has continued to do so since. Until.... This morning, 6/1/2015 I tried to shower. The heating was on very low overnight so was not actually on when I tried to shower. The shower would not even warm up. But, the hot tap in the bathroom sink warmed up and if I pulled the mixer plug and put the shower back to the bath taps, then the water would heat up. But as soon as I put it back to shower it would run cold again. I checked the boiler after and the pressure has held since it was fixed on 28/12. In fact the pressure hasn't dropped at all since and is still between 1.5 and 2 bar on the boiler. And the shower mixer had worked fine since. So my question is, why would I suddenly start having problems again with the water running cold as soon as I use the mixer and try to use the shower?
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Pilot Light Heating
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