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Don't ask me i haven't seen the photos,How many elbows you going to have on a 1 metre run!!!!
Don't ask me i haven't seen the photos,How many elbows you going to have on a 1 metre run!!!!
Nissan luxury Coupe
Oh well...another school day.I stand corrected.Plenty of 60Kw boilers in domestic properties, and plenty of 50mm gas pipe in larger domestic properties.
Oh well...another school day.I stand corrected.
Out of curiosity, do you mean the new boiler won't be used for DHW?had a couple of quotes for replacing an existing vented CH System S plan, going to pressurised system (not hot water ) either WB or Vaillent. 15kw. (system boiler or heat only.
last quote said that 15mm gas feed is OK so long as there is 16.5 operating pressure, is that correct figure please? no other gas appliances in the property (flat).
thanks
The gas pressure at the appliance is affected by three things - diameter of pipe, length of pipe, and number of changes in direction. 16.5mBar is acceptable at the appliance only when 17.5mbar or less is being produced by the meter, as the maximum permissible difference between the two is 1 mBar. In reality though, gas suppliers are supposed to provide a minimum of 19mBar at tbe meter, so your existing pipe run may actually already be undersized for your existing boilerThanks for replies, I suppose that I just assumed that there has to be 16.5 coming out of the gas pipe into the boiler but looks like not so simple. I know a bit about CH systems but nothing about gas pressure, I don't really want to pay for increasing the pipe size to 22mm unless I have to. I thought that 15kw is one of the smaller boilers so not so much gas required?
Thanks for replies, I suppose that I just assumed that there has to be 16.5 coming out of the gas pipe into the boiler but looks like not so simple. I know a bit about CH systems but nothing about gas pressure, I don't really want to pay for increasing the pipe size to 22mm unless I have to. I thought that 15kw is one of the smaller boilers so not so much gas required?
But 17.5mbar at the meter would be a fault anyway. If that's the case the problem is supply pressure into the meter, or the meter characteristics (most likely the former) and the gas company should be informed.16.5mBar is acceptable at the appliance only when 17.5mbar or less is being produced by the meter
You haven't given any lengths, but if the disused 22mm connection is after the buried section, that part is unlikely to be smaller, might even be 28mm. Presumably replacing the buried part is your main concern, so on that basis upping it is unlikely to be needed. But losses need checking.thanks for your comments
fixitflav , sorry I wsn't clear, using old copper hot water cylinder indirect
The meter is in a cupboard outside the front door, 28mm going in and out of the meter then the pipe goes into a concrete floor to the kitchen where it must split, there is a 22mm connection coming out of the wall (not used) at the other end of the kitchen to the boiler (15mm connection)
The previous quote said 15mm gas feed is OK so long as there is 16.5 operating pressure
Not necessarilyBut 17.5mbar at the meter would be a fault anyway.
I read it as being at the boiler inlet, but I agree it's not clear. If it's at the meter outlet it's even further outside the regs.Operating pressure taken from where?
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