I am having a worcester 18ri (18Kw) boiler installed in my garage as a replacement to an old 15Kw Ideal classic currently installed in my kitchem. The existing boiler takes its gas feed using about 2metres of 15mm pipe into a 22mm feed that is about 8-10 metres from the metre.
The guy installing the new boiler has extended the existing 15mm pipe from the old boiler now extending to about 7m of 15mm pipe. This worries me as the wORCESTER manual states the 18ri should use 22mm. I spoke to the heating engineer about this and he told me that providing the working pressure is fine then this shouldnt be a problem. As I am concerned it might cause me future problems I need some advice:-
1.) Does it sound reasonable to operate an 18KW heat only boiler on 7metres of 15mm pipe further connected via 22m to the meter?
2.) Is he correct that providing the working pressure is ok then it should be fine?
3.) Reading the manual it states that the inlet pressure should be 16.5-20.5mbar when set at maximum with a drop of no more than 2.5mbar from meter to boiler test point. I assume this should be tested with any other gas appliances there are in the house on full also? We only have a gas fire ie no gas hob so I intend to ask him to take the reading when the fire is also on full. Is that the right thing to do?
4.) I also notice in the manul that it states that the pressure drop over internal pipe work (meter to bolier) should not be amore than 1mbar. Am I correct to assume this would be measured at the bolier inlet test point also, but without the boiler firing?
5.) Should the engineer measure the meter pressure with gas appliances on or off as the reference? I understand this should be 19-23mbar.
6.) If the gas pressure at the bolier is borderline ie 16.5mbar in the middle of summer when nobody has their heating on i sit likely to drop in winter when everyone else is using their boliers etc. I guess I am asking if the mains gas pressure in the UK fluctuates much between summer and winter etc.
Thanks for any guidance. I am tempted to ask the guy to simply replace teh 15mm pipe with 22mm, but he seems like a nice chap who knows his stuff.
The guy installing the new boiler has extended the existing 15mm pipe from the old boiler now extending to about 7m of 15mm pipe. This worries me as the wORCESTER manual states the 18ri should use 22mm. I spoke to the heating engineer about this and he told me that providing the working pressure is fine then this shouldnt be a problem. As I am concerned it might cause me future problems I need some advice:-
1.) Does it sound reasonable to operate an 18KW heat only boiler on 7metres of 15mm pipe further connected via 22m to the meter?
2.) Is he correct that providing the working pressure is ok then it should be fine?
3.) Reading the manual it states that the inlet pressure should be 16.5-20.5mbar when set at maximum with a drop of no more than 2.5mbar from meter to boiler test point. I assume this should be tested with any other gas appliances there are in the house on full also? We only have a gas fire ie no gas hob so I intend to ask him to take the reading when the fire is also on full. Is that the right thing to do?
4.) I also notice in the manul that it states that the pressure drop over internal pipe work (meter to bolier) should not be amore than 1mbar. Am I correct to assume this would be measured at the bolier inlet test point also, but without the boiler firing?
5.) Should the engineer measure the meter pressure with gas appliances on or off as the reference? I understand this should be 19-23mbar.
6.) If the gas pressure at the bolier is borderline ie 16.5mbar in the middle of summer when nobody has their heating on i sit likely to drop in winter when everyone else is using their boliers etc. I guess I am asking if the mains gas pressure in the UK fluctuates much between summer and winter etc.
Thanks for any guidance. I am tempted to ask the guy to simply replace teh 15mm pipe with 22mm, but he seems like a nice chap who knows his stuff.
