Confused over water pressure numbers

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This started because I need to buy new kitchen tap and need to work out pressure first.

I got a pressure gauge and stuck it on the kitchen mixer tap with a rubber adaptor. This showed me: Cold 1.3 Bar, Hot 1.9 Bar.

Now here is the puzzle: until I measured it I believed that I had very low water pressure. For instance if the washing machine and dishwasher both try to fill at the same time they can't. Or if I run the cold tap when one is filling it stops it filling. The garden tap (which comes straight off under the kitchen sink) won't run a sprinkler well and won't trigger my pressure washer.

So, I am puzzled as those numbers are apparently classed as High Pressure by tap makers.

The cold is mains fed and the hot comes from a cylinder which is filled from a cold tank in the loft. The cylinder is on the ground floor near the kitchen (so all water for upstairs is pumped - used to be a bungalow).

My instinct tells me that perhaps the gauge is wrong but any advice is welcome!
 
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I think you are probably doing something wrong ,or the gauge is duff. If the hot tap that you took the reading from is gravity fed ,and not pumped ,then its highly unlikely to have 1.9 bar pressure ,which would require around
19 metres vertical distance from the loft tank to the tap outlet.
 
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.... and google a proper water pressure gauge, check that it has an appliance connector (SF have them) and then test your mains pressure from the valve that supplies your washing machine. When you're checking that value, run another 1 or 2 cod taps at the same and see what the pressure reading changes too (Static and working(dynamic) pressures). Once that's done fill a bucket up in the sink, time it over a minute & measure the amount of water and that's your L/Min figure.

Bring those value back here.
 
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Thanks guys. Now I know that it is static pressure I am measuring but don't know if that is what the tap makers refer to!

This is the gauge I am using: http://amzn.eu/d/2yJnM0v and i can connect it "properly" to the garden tap which comes off the pipework for the kitchen tap. This gives the same result.

I am puzzled by a gravity setup though. As the hot water exits the cylinder and runs out of the tap then it is obviously replaced in the cylinder with cold. Why does that need to come from a header tank rather than the mains (especially as my cylinder is on the ground floor)? Does the inlet pressure of the cold water filling the cylinder have an effect on the pressure of the hot water coming out from the cylinder?

I'll repeat the tests and check the results.
 
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Hot water expands when heated ,your system has an open vent pipe in the loft to accommodate this ,and provide an escape route into the loft tank ( should water temp get excessive ,say to boiling point ).
 
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Hot water expands when heated ,your system has an open vent pipe in the loft to accommodate this ,and provide an escape route into the loft tank ( should water temp get excessive ,say to boiling point ).
Thanks Terry. Yes. I understand that but am puzzled why the cold feed into the cylinder needs to be from a tank rather than the main,
 
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If you connected your cylinder to the cold mains , water would run out the open vent pipe in the loft ,into the loft tank ,overflowing it ,non stop !!
 
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Thanks guys. Now I know that it is static pressure I am measuring but don't know if that is what the tap makers refer to!

This is the gauge I am using: http://amzn.eu/d/2yJnM0v and i can connect it "properly" to the garden tap which comes off the pipework for the kitchen tap. This gives the same result.

I am puzzled by a gravity setup though. As the hot water exits the cylinder and runs out of the tap then it is obviously replaced in the cylinder with cold. Why does that need to come from a header tank rather than the mains (especially as my cylinder is on the ground floor)? Does the inlet pressure of the cold water filling the cylinder have an effect on the pressure of the hot water coming out from the cylinder?

I'll repeat the tests and check the results.
Okay, let's forget about the hot pressure - I am officially a numpty: the hot IS pumped and I am getting 3.6Bar now that I have fitted the gauge properly!

Cold is a different story:

Pressure 1.3

Turn on tap in garage (which is directly off the main as it enters the property and before anything else on the system) and pressure drops to zero. This is more like what I thought: we are at the top of a hill and I thought the pressure was poor.

Flow rate is 7L/M.

So it seems that in terms of getting a mixer tap I have a mixed picture: high pressure hot, high pressure cold but only if nothing else running.
 
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The only way you'll get that balanced for a new mixer would be to fit a pressure reducing valve to the hot and then get an LP mixer tap for the kitchen or bring a cold from the pump to the mixer location and then have a separate outlet and tap, for drinking water.
 
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Do you currently have a kitchen mixer tap ,and if so how does it perform ?
 
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The only way you'll get that balanced for a new mixer would be to fit a pressure reducing valve to the hot and then get an LP mixer tap for the kitchen or bring a cold from the pump to the mixer location and then have a separate outlet and tap, for drinking water.
Are you saying that pumped water shouldn't be drunk? Both the downstairs and upstairs bathrooms here have the cold pumped.
 

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