Home |
Search |
Today's Posts |
|
UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
|
#1
|
|||
|
|||
more boiler questions.. mains pressure this time.
If I can get my sealed system up to at least 1.5bar by filling it from the
mains filling loop, does this mean I have enough pressure to fit a combi boiler? Jim |
#2
|
|||
|
|||
If I can get my sealed system up to at least 1.5bar by filling it from the
mains filling loop, does this mean I have enough pressure to fit a combi boiler? What kind of flow do you get from your taps in litres per minute ? -- Please add "[newsgroup]" in the subject of any personal replies via email --- My new email address has "ngspamtrap" & @btinternet.com in it ;-) --- |
#3
|
|||
|
|||
"Colin Wilson" wrote in message
t... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? What kind of flow do you get from your taps in litres per minute ? 9 litres a minute from the kitchen tap (the rest are off the cold water tank) |
#4
|
|||
|
|||
On Tue, 19 Oct 2004 22:05:42 +0100, "JJJ" wrote:
"Colin Wilson" wrote in message et... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? What kind of flow do you get from your taps in litres per minute ? 9 litres a minute from the kitchen tap (the rest are off the cold water tank) Then the answer is that the results will be disappointing. You could look at getting the supply improved or perhaps the stop tap is partly closed. This is the lowest legal minimum for a water supply. Generally for a mains fed system, you need at least 20lpm. If you must use a combi because you would like to get rid of the HW cylinder, then look at one that will accept its water feed from a roof tank. ..andy To email, substitute .nospam with .gl |
#5
|
|||
|
|||
"Andy Hall" wrote in message ... On Tue, 19 Oct 2004 22:05:42 +0100, "JJJ" wrote: "Colin Wilson" wrote in message et... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? What kind of flow do you get from your taps in litres per minute ? 9 litres a minute from the kitchen tap (the rest are off the cold water tank) Then the answer is that the results will be disappointing. You could look at getting the supply improved or perhaps the stop tap is partly closed. This is the lowest legal minimum for a water supply. Generally for a mains fed system, you need at least 20lpm. If you must use a combi because you would like to get rid of the HW cylinder, then look at one that will accept its water feed from a roof tank. Check that if you have a stopcock or isolation valve/tap in the line that it is fully open. My initial flow rates were rather disappointing until I realised that the combi was fed from an isolation tap, which was only cracked open halfway. Andy. |
#6
|
|||
|
|||
"andrewpreece" wrote in message
... "Andy Hall" wrote in message ... On Tue, 19 Oct 2004 22:05:42 +0100, "JJJ" wrote: "Colin Wilson" wrote in message et... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? What kind of flow do you get from your taps in litres per minute ? 9 litres a minute from the kitchen tap (the rest are off the cold water tank) Then the answer is that the results will be disappointing. You could look at getting the supply improved or perhaps the stop tap is partly closed. This is the lowest legal minimum for a water supply. Generally for a mains fed system, you need at least 20lpm. If you must use a combi because you would like to get rid of the HW cylinder, then look at one that will accept its water feed from a roof tank. Check that if you have a stopcock or isolation valve/tap in the line that it is fully open. My initial flow rates were rather disappointing until I realised that the combi was fed from an isolation tap, which was only cracked open halfway. Andy. will do. thanks, Jim |
#7
|
|||
|
|||
andrewpreece wrote:
Check that if you have a stopcock or isolation valve/tap in the line that it is fully open. My initial flow rates were rather disappointing until I realised that the combi was fed from an isolation tap, which was only cracked open halfway. Some combis control the flow rate of hot water produced, some dont. Hence in winter (i.e. cold incoming water), the ones with control will produce water at the same temperature as before, but a lower flow rate. The ones without control will produce water at the same rate as before, but at a lower temperature. Sometimes I have seen the input stopcock partially turned off like this on boilers that do not limit hot water flow rate so as to ensure the hot water temperature remains hot enough without the user having to remember not to turn the hot bath tap full on. -- Cheers, John. /================================================== ===============\ | Internode Ltd - http://www.internode.co.uk | |-----------------------------------------------------------------| | John Rumm - john(at)internode(dot)co(dot)uk | \================================================= ================/ |
#8
|
|||
|
|||
In an earlier contribution to this discussion,
JJJ wrote: If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? Jim No! It simply tells you that you have a *static* pressure of at least 1.5bar. It tells you nothing about the *flow rate* which your mains supply can sustain. I think the pundits say that you need about 20 litres per minute. -- Cheers, Set Square ______ Please reply to newsgroup. Reply address is invalid. |
#9
|
|||
|
|||
If I can get my sealed system up to at least 1.5bar by filling it from the
mains filling loop, does this mean I have enough pressure to fit a combi boiler? Yes it does. 1.5 bar is easily enough for a combi boiler. However, it doesn't tell you if the flow rate is good enough. Flow rate is more important than the pressure. You mention 9 lpm elsewhere, which is not enough flow rate. However, this poor flow rate might be for a fixable reason, such as a broken/partially closed stopcock, or a modern styled tap with very narrow waterways that is not designed to pass more than that flow rate. (I'm not suggesting that the tap would need replacing, just that it might affect the feasibility test). If you have a garden tap, try measuring the flow rate off that instead. Christian. |
#10
|
|||
|
|||
"Christian McArdle" wrote in message
. net... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? Yes it does. 1.5 bar is easily enough for a combi boiler. However, it doesn't tell you if the flow rate is good enough. Flow rate is more important than the pressure. You mention 9 lpm elsewhere, which is not enough flow rate. However, this poor flow rate might be for a fixable reason, such as a broken/partially closed stopcock, or a modern styled tap with very narrow waterways that is not designed to pass more than that flow rate. (I'm not suggesting that the tap would need replacing, just that it might affect the feasibility test). If you have a garden tap, try measuring the flow rate off that instead. Christian. ok, I've measured it at 15 litres/min outside at the garden tap. Better, but not outstanding.... Jim |
#11
|
|||
|
|||
ok, I've measured it at 15 litres/min outside at the garden tap. Better,
but not outstanding.... I think that`s similar to ours, and recently had our first central heating system installed - a Worcester Bosch 28 SiII IIRC... Works just fine :-) -- Please add "[newsgroup]" in the subject of any personal replies via email --- My new email address has "ngspamtrap" & @btinternet.com in it ;-) --- |
#12
|
|||
|
|||
On Wed, 20 Oct 2004 21:47:59 +0100, Colin Wilson
wrote: ok, I've measured it at 15 litres/min outside at the garden tap. Better, but not outstanding.... I think that`s similar to ours, and recently had our first central heating system installed - a Worcester Bosch 28 SiII IIRC... Works just fine :-) I guess that it depends on what your requirements and expectations are. A loft tank arrangement with 22mm pipework etc. can comfortably deliver 15-20lpm per tap albeit at lowish pressure - with a pump rather more. If you are used to this, then 10-15lpm is going to seem poor. OTOH, if you are used to an electric shower, it may appear brilliant. ..andy To email, substitute .nospam with .gl |
#13
|
|||
|
|||
On Wed, 20 Oct 2004 20:32:56 +0100, "JJJ" wrote:
"Christian McArdle" wrote in message If you have a garden tap, try measuring the flow rate off that instead. Christian. ok, I've measured it at 15 litres/min outside at the garden tap. Better, but not outstanding.... Jim It suggests that by some improvement to internal plumbing, perhaps stop tap, etc. you could get a pretty good result. ..andy To email, substitute .nospam with .gl |
#14
|
|||
|
|||
On Wed, 20 Oct 2004 22:49:02 +0100, Andy Hall wrote:
On Wed, 20 Oct 2004 20:32:56 +0100, "JJJ" wrote: "Christian McArdle" wrote in message If you have a garden tap, try measuring the flow rate off that instead. Christian. ok, I've measured it at 15 litres/min outside at the garden tap. Better, but not outstanding.... Jim It suggests that by some improvement to internal plumbing, perhaps stop tap, etc. you could get a pretty good result. I agree that arttention to detail can make the difference here. Using full bore 1/4 turn stop taps and getting the cold feed to the boiler before other usags can make a difference. -- Ed Sirett - Property maintainer and registered gas fitter. The FAQ for uk.diy is at www.diyfaq.org.uk Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html |
#15
|
|||
|
|||
On Wed, 20 Oct 2004 20:32:56 +0100, JJJ wrote:
"Christian McArdle" wrote in message . net... If I can get my sealed system up to at least 1.5bar by filling it from the mains filling loop, does this mean I have enough pressure to fit a combi boiler? Yes it does. 1.5 bar is easily enough for a combi boiler. However, it doesn't tell you if the flow rate is good enough. Flow rate is more important than the pressure. You mention 9 lpm elsewhere, which is not enough flow rate. However, this poor flow rate might be for a fixable reason, such as a broken/partially closed stopcock, or a modern styled tap with very narrow waterways that is not designed to pass more than that flow rate. (I'm not suggesting that the tap would need replacing, just that it might affect the feasibility test). If you have a garden tap, try measuring the flow rate off that instead. Christian. ok, I've measured it at 15 litres/min outside at the garden tap. Better, but not outstanding.... Not brilliant but likely workable. -- Ed Sirett - Property maintainer and registered gas fitter. The FAQ for uk.diy is at www.diyfaq.org.uk Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Regulator pressure increases over time - why?? | Home Repair | |||
Heat banks (again!) | UK diy | |||
Near death boiler + replacing a boiler | UK diy | |||
Boiler pilot light went out | UK diy | |||
New Combi boiler | UK diy |