Questions about pressure

G

Goldspoon

Have a couple of questions I just want to confirm answers to... hope somebody can answer (yes/no is fine to save your time but if no any thoughts appreciated:)

Combi boiler: the pressure as indicated by the guage on the boiler (clock type face or digital display) only indicates the pressure of the primary heating circuit (hence using the filling loop to boost this circuit). Am I correct?

Combi boiler: Hot water is at a pressure dictated by the boiler and there is usually no way to see on any guage what this pressure is - it is usually mains pressure reduced down by the boiler so the boiler has chance to heat it before it passes on it's way to outlets...

Combi boiler: Cold water is at mains pressure not reduced down.

Unvented cylinder: the pressure as indicated by the guage on the cylinder (clock type face on the one I know) indicates the pressure of the primary heating circuit (hence using the filling loop to boost this circuit). Am I correct?

Unvented cylinder: the hot water in the cylinder (bath water etc.) is only under pressure doe to this cylinder being mains fed and once again there is usually no guage to check what this pressure is?

I know that these are fairly basic questions but I am striving to learn more about CH systems in particular :)
 
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Have a couple of questions I just want to confirm answers to... hope somebody can answer (yes/no is fine to save your time but if no any thoughts appreciated:)

Combi boiler: the pressure as indicated by the guage on the boiler (clock type face or digital display) only indicates the pressure of the primary heating circuit (hence using the filling loop to boost this circuit). Am I correct?

Pretty much, Yes

Combi boiler: Hot water is at a pressure dictated by the boiler and there is usually no way to see on any guage what this pressure is - it is usually mains pressure reduced down by the boiler so the boiler has chance to heat it before it passes on it's way to outlets...

Essentially, yes.

Combi boiler: Cold water is at mains pressure not reduced down.

Unvented cylinder: the pressure as indicated by the guage on the cylinder (clock type face on the one I know) indicates the pressure of the primary heating circuit (hence using the filling loop to boost this circuit). Am I correct?

Summink like that, Yes

Unvented cylinder: the hot water in the cylinder (bath water etc.) is only under pressure doe to this cylinder being mains fed and once again there is usually no guage to check what this pressure is?

Mmm, Yes

I know that these are fairly basic questions but I am striving to learn more about CH systems in particular :)

:rolleyes:
 
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Unvented cylinder: the hot water in the cylinder (bath water etc.) is only under pressure doe to this cylinder being mains fed and once again there is usually no guage to check what this pressure is?

The flow/pressure of the hot water at the taps is due to the head of pressure of the cold water store in the loft feeding the cylinder, not mains pressure. If the cold water store feeding the cylinder is 5 meters above the cylinder you will get a better flow of hot than if it was 2 meters......

At least thats what I think....will wait to see if I am shot down on that one!
 
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The flow/pressure of the hot water at the taps is due to the head of pressure of the cold water store in the loft feeding the cylinder, not mains pressure. If the cold water store feeding the cylinder is 5 meters above the cylinder you will get a better flow of hot than if it was 2 meters......

At least thats what I think....will wait to see if I am shot down on that one!

He's talking about an unvented cylinder mate ;)
 
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OOOPS! Must learn to ready slower and with a couple let of the old apple juice! Sorry guys
 

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