The forum has been very useful for our ongoing bathroom saga...but we have yet another problem.
We had a bathroom fitted and after lots of problems (missed opportunities for thicker pipes, builders walking out...) ended up with very low water pressure and old 15mm pipes. We have a gravity fed system cold water tank in the loft, bathroom and hot water cylinder in cupboard on the first floor. To solve the low pressure the plumber suggested to fit two single Salamander pumps, one in the loft for the cold water for bath and shower and one next to the hot water cylinder for the hot water (feeding the whole hot water supply). The bathroom floor is tiled and we couldn't get at the pipe work anymore to isolate the bath/shower for a twin pump.
The thermostatic shower valve (grohe, low pressure) now causes the hot water pump to pulsate on and off and so do the other taps if very little hot or cold is set (i.e. mixing luke warm). The plumber had never seen this before and the Salamander hotline person now says that we need two negative head kits RCM3 to convert to activate pumps to pressure rather than flow (we don't have a negative head situation). Very annoying as it's another £230 for two and we are worried to throw good money after bad if this still doesn't work as there aren't any guarantees.
On top of that we find the two pumps very noisy. They already sit on foam then paving slab then foam and feet insulated, but it seems that they and the pipe work still causes a deep humming noise that travels along the floor and which you can hear in the whole house.
Has anyone had experience of the RCM3 things working in a positive head situation, and/or has successfully contained the pump noise a bit?
Many thanks.
We had a bathroom fitted and after lots of problems (missed opportunities for thicker pipes, builders walking out...) ended up with very low water pressure and old 15mm pipes. We have a gravity fed system cold water tank in the loft, bathroom and hot water cylinder in cupboard on the first floor. To solve the low pressure the plumber suggested to fit two single Salamander pumps, one in the loft for the cold water for bath and shower and one next to the hot water cylinder for the hot water (feeding the whole hot water supply). The bathroom floor is tiled and we couldn't get at the pipe work anymore to isolate the bath/shower for a twin pump.
The thermostatic shower valve (grohe, low pressure) now causes the hot water pump to pulsate on and off and so do the other taps if very little hot or cold is set (i.e. mixing luke warm). The plumber had never seen this before and the Salamander hotline person now says that we need two negative head kits RCM3 to convert to activate pumps to pressure rather than flow (we don't have a negative head situation). Very annoying as it's another £230 for two and we are worried to throw good money after bad if this still doesn't work as there aren't any guarantees.
On top of that we find the two pumps very noisy. They already sit on foam then paving slab then foam and feet insulated, but it seems that they and the pipe work still causes a deep humming noise that travels along the floor and which you can hear in the whole house.
Has anyone had experience of the RCM3 things working in a positive head situation, and/or has successfully contained the pump noise a bit?
Many thanks.
