In my mother-in-laws house she has a problem where the stored hot water tank is overflowing. The ball cock has been adjusted several times and finally a plumber has diagnosed the fault to the thermostatic bath mixer. He says I need to fit a non return valve to preferably the hot side as the higher cold pressure is backfilling the hot.
This does make sense to me as it's stored hot water but mains cold. The problem occurs even when the taps are switched off.
Can I confirm I need to fit a swing valve rather than a check valve as it's gravity hot water (stored only on the 1st floor)? Also where can I fit the valve? Presumably the best place is by the tap causing the problem but this involves ripping the bathroom apart. Can it be fitted elsewhere in the hot supply line, for example nearer to the tank? I understand if a swing valve the orientation is important.
Finally, the flow of hot water through this particular thermostatic mixer tap has always been very poor (it was good prior with separate taps), could this be related? I can't remember what pressure the taps were rated at but I'm sure they were suitable for low pressure.
This does make sense to me as it's stored hot water but mains cold. The problem occurs even when the taps are switched off.
Can I confirm I need to fit a swing valve rather than a check valve as it's gravity hot water (stored only on the 1st floor)? Also where can I fit the valve? Presumably the best place is by the tap causing the problem but this involves ripping the bathroom apart. Can it be fitted elsewhere in the hot supply line, for example nearer to the tank? I understand if a swing valve the orientation is important.
Finally, the flow of hot water through this particular thermostatic mixer tap has always been very poor (it was good prior with separate taps), could this be related? I can't remember what pressure the taps were rated at but I'm sure they were suitable for low pressure.