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Okay, here's my first large, (Bernie2 and Plouanse) style thread starter
I am sick to death of incorrect pump installs both by DIY and cowboy plumbers so I thought I would give some in sight as to why they have to be installed in certain ways
The most common pumps are the positive head centrifugal pumps
Usually twin with a motor inbetween two impellars
Common install faults:
Why not a Surrey Flange? (although I know Slamander advise this)
Well the surrey is a top feed flange and is actually restirctive have a bore of about 8mm. It is sited at the top of the cylinder where most the air is and so draws this in. Air in a pump will cause it to fail. Fit it with a Essex all the way
Why not feed of the bath taps? A pump requires dedicated supply to it to ensure it has enough water to fill the impellars and fire the water out
Why not fit a shower pump to taps? I see this a loot and people think its fine.... IT'S NOT. A Centrifugal pump will fail on pillar taps as only one side is being used yet the other side is spinning without any water in it. The rate they spin at is very high causing a lot of heat on the shaft seal. If this goes pump is shot. We even the hot water acts as a coolant to the shaft seal.
Why not fit it under the bath? A lot fitted here are fitted on to the bath feeds but mainly you do not get the required ventilation unless you cut an ugly hole in the bath panel.
Why not use ball o fix valves? Whilst the pump does need isolation to it the ball o fix is a restrictive valve ( i know you can get the odd ones that aren't but they are uncommon). Do it right and use gate valves of lever action
Why fit onto the anti vibration feet or matting? Pumps spinning equals pumps wobbling equals noise. The anti virbation feet help reduce this a lot.
Why fit in the airing cupboard? The pumps are designed to push water and not pull it over a distance. The aqiring cupboard is also a good place for ventilation.
Why fit the cold feedin the CWST below the hot feed to the Hot water Cylinder? This is not a must but is a safety precaution as if you run the cold water tank dry the hot water will stop before the cold.
Hopefully this will clear a few things up
It does have to be an Essex as I know these are fiddly to say the least but easier to fit if you don fully drain the hot water cylinder.
If not you can fit the hot water feed to the first draw off below the vent tee. (giving your self about 6 inches below the tee)
NB:
Alhough fixing faults gets me call outs and money I can guarantee who ever installed it is not on this forum and will continue and DIYers will always try and fail. I'm just sick of them
I am sick to death of incorrect pump installs both by DIY and cowboy plumbers so I thought I would give some in sight as to why they have to be installed in certain ways
The most common pumps are the positive head centrifugal pumps
Usually twin with a motor inbetween two impellars
Common install faults:
Why not a Surrey Flange? (although I know Slamander advise this)
Well the surrey is a top feed flange and is actually restirctive have a bore of about 8mm. It is sited at the top of the cylinder where most the air is and so draws this in. Air in a pump will cause it to fail. Fit it with a Essex all the way
Why not feed of the bath taps? A pump requires dedicated supply to it to ensure it has enough water to fill the impellars and fire the water out
Why not fit a shower pump to taps? I see this a loot and people think its fine.... IT'S NOT. A Centrifugal pump will fail on pillar taps as only one side is being used yet the other side is spinning without any water in it. The rate they spin at is very high causing a lot of heat on the shaft seal. If this goes pump is shot. We even the hot water acts as a coolant to the shaft seal.
Why not fit it under the bath? A lot fitted here are fitted on to the bath feeds but mainly you do not get the required ventilation unless you cut an ugly hole in the bath panel.
Why not use ball o fix valves? Whilst the pump does need isolation to it the ball o fix is a restrictive valve ( i know you can get the odd ones that aren't but they are uncommon). Do it right and use gate valves of lever action
Why fit onto the anti vibration feet or matting? Pumps spinning equals pumps wobbling equals noise. The anti virbation feet help reduce this a lot.
Why fit in the airing cupboard? The pumps are designed to push water and not pull it over a distance. The aqiring cupboard is also a good place for ventilation.
Why fit the cold feedin the CWST below the hot feed to the Hot water Cylinder? This is not a must but is a safety precaution as if you run the cold water tank dry the hot water will stop before the cold.
Hopefully this will clear a few things up
It does have to be an Essex as I know these are fiddly to say the least but easier to fit if you don fully drain the hot water cylinder.
If not you can fit the hot water feed to the first draw off below the vent tee. (giving your self about 6 inches below the tee)
NB:
Alhough fixing faults gets me call outs and money I can guarantee who ever installed it is not on this forum and will continue and DIYers will always try and fail. I'm just sick of them
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