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mutley racers

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Gas Engineer
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Hi Guys, what would you recommend, house has 20 litres a minute with 18 litres working, only one bathroom and will not change. Cheers
 
30kw and a flow restrictor on the kitchen hot tap
 
32 kw depends what the load on the hot water system?
 
Thanks chaps. The original combo was 30kw so I put in a 32. Now I replaced 10 metres of the original 22mm gas pipe with 28mm working back from the boiler. Was expecting this to give it a nice boost. Well it didn't, only getting 14.5 mb working at appliance with 21 at metre. No other appliances. About 8 metres of 22mm from meter to 28mm. Gutted
 
You mean a vogue 32?
any chance of a restriction in the existing 22mm?
Seems a big loss over that length of pipe
 
You mean a vogue 32?
any chance of a restriction in the existing 22mm?
Seems a big loss over that length of pipe

That's the one.

Yes seems like a rather large drop hey. I cannot tell with the existing as it's under a hardwood ground floor. Going to have to put in test points where I can I think to see
 
Thanks chaps. The original combo was 30kw so I put in a 32. Now I replaced 10 metres of the original 22mm gas pipe with 28mm working back from the boiler. Was expecting this to give it a nice boost. Well it didn't, only getting 14.5 mb working at appliance with 21 at metre. No other appliances. About 8 metres of 22mm from meter to 28mm. Gutted

It would seem to me that you did not check the 8m of 22 from meter
for blockage.

Could be any number of things, black powder, water, I have found
plaster and even a *** butt in pipe work in the past. Is pipe work
clear of solder snots.

What was WP like on original boiler?

Could only be undersized/ blocked pipe work.
 
Hi, no I did not check to see if it was blocked. Hard when under the floor. So could not check for snot either.

The boiler was knackered so just pulled it out.

I am thinking of a blockage though. Hopefully no cigarette butt's in this pipe
 
Did you do a working gas pressure at the meter and at the boiler gas valve if so what were they it seems a big drop over that distance , you would have been better to upsize off the meter in 28mm as much as you could ?isolate and disconnect the gas meter turn it upside down on a dust sheet to see if there is any rust or debris in it . good luck kop
 
Did you do a working gas pressure at the meter and at the boiler gas valve if so what were they it seems a big drop over that distance , you would have been better to upsize off the meter in 28mm as much as you could ?isolate and disconnect the gas meter turn it upside down on a dust sheet to see if there is any rust or debris in it . good luck kop

Hi . Yes I did. Working pressure at the meter is 21mb. I ran it back from the boiler as there was only 500mm copper tube from meter before going into the floor which is covered with hardwood flooring.

Will give the meter a shake when I go back.

Thanks all
 
You mention the 14.5 mbar working pressure at boiler, that's OK due to pressure loss through the valve. But more important what is the inlet? That should be no more than 1 mbar difference from the 21 mbar at the meter. But also the Vogue range is able to deliver it’s full output at inlet pressures as low as 14mb. What was the gas rate? it should be approx 3.314 m3/hr or 117.1 ft3/hr at max.
 
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is that at the gas valve or the actual inlet to the boiler as some lose quite a lot of pressure at the valve thats why some put a test point on the isolation valve now
 
is that at the gas valve or the actual inlet to the boiler as some lose quite a lot of pressure at the valve thats why some put a test point on the isolation valve now


It's at the test point on isolation point. But the manual still says it can have a drop through that if you look on page 12 I think.
 
Sorry to say out of spec max at the ISO point 18 mbar with 19 at the meter

If you test at the gas valve you can have as low as 14.5 mbar
 
That is strange ISO valve fully open ?

And I would cut a test point in below the boiler
 
Hate ideal there the only ones with big drops on there valves
 
No drop allowed on the vogue gas valve as it's 22mm
It's the 15mm in the logic that a drop is allowed
 
Ideal state it will work on a 14mbar gas pressure but we all know your cant have 21mbar at the meter and 14.5mbar at the boiler you will probably loose 1.5 mbar through the gas valve so your still 5 mbar down , what gauge did you use for the test? use a water gauge and zero it before connecting they cant lie cheers kop
 
Certainly sounds like a restriction in the pipework somewhere
 
I have been back, cut a test point in just before boiler service valve on 28mm pipe. 14mm. Installed another 10 metres of 28mm and now getting 16.5mb. Only 1 metre left of 22mm coming off the gas meter. I had gas meter off and shook it about and nothing came out. I must admit, I have never had this before. This should easily be running a 35kw boiler? Maybe a faulty meter? Thanks for the advice guys
 
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