Gas Boiler help

keystone

Pennypins wrote: »

I have good information that has been quoted from the CORGI Gas Regulations Handbook..........

I think you mean the appallingly overpriced publications that are published by the kennel club. Please do not give the impression that Corgi has either written the GSIUR, is responsible for them or is the copyright holder. That may not have been your intention but that is how your post reads.

Cheers

heating-eng

Pennypins wrote: »

Hello,

You need to find out if the pipework is iron or copper.

Copper piping has a outside diameter of 15 or 22mm.

Iron piping is measured in inches, and is measured from the inside at 20mm for 3/4" and 15mm for 1/2".

It doesn't matter about the size but you are only allowed one millibar drop in pressure from the gas meter to the last appliance on gas.

So you may have to strip out the pipework from the gas meter to the boiler and re-run a bigger size either 22mm or 28mm depending on what the new boiler requires and distance from the meter and how many bends or elbows appear in the pipework. And the pipework has to be run above floor level (not under floorboards).

Hope this helps.

you will find that most (not all)combi boilers need a 22mm gas pipe as per manfac instructions ...
one milibar drop is ture but still need to go by what the instruction for the boiler says ..

heating-eng

needhelp1 wrote: »

Hello,

My boiler has just packed up and I have had a Gas Safe Engineer around to give me a quote for a new boiler.

I have been told that as the mains gas pipe is 18mm I can only have a 24kW boiler installed or have new pipework too which will be very expensive.

I have been having a look at boilers online and it appears that even 24kW combi boilers need 22mm piping.

I have measured the pipe diameter myself and it measures 21mm (outside) so I am now confused. I assume the engineer was referring to the inside diameter??

Please can someone knowledgeable tell me if my pipes are definitely suitable for a boiler that asks for 22mm mains pipes and whether I risk voiding the manufacturers warranty if I go ahead and use the current pipes.

Many thanks
needhelp1

can you count how many pipes come down from the boiler ..how many are 22mm and how many are 15mm ..

Razor

No combi manufacturer specifies a 22mm supply, it's up to the RGI to size the pipe accordingly.

I'm interested by your signature does it mean that you are on the GSR register but not a professional or correct?? Weird

heating-eng

Razor wrote: »

No combi manufacturer specifies a 22mm supply, it's up to the RGI to size the pipe accordingly.

I'm interested by your signature does it mean that you are on the GSR register but not a professional or correct?? Weird

been fitting boilers for years mate you havnt got a clue most boilers state 22mm ...

yes i am on the reg thanks. it means that sometimes you are better to get somebody in to see the problem as its not always that easy on a chat room to be 100% correct ..

Razor

Could you please state which manufacturers specify 22mm?

Fitted a Vaillant 937 last week, corrected length of gas run was 25 metres. 22mm ok was it?

heating-eng

Razor wrote: »

Could you please state which manufacturers specify 22mm?

Fitted a Vaillant 937 last week, corrected length of gas run was 25 metres. 22mm ok was it?

how it is normally worded is ..gas supply should not be smaller than boiler inlet ..ie ..most combi boilers have a 22mm gas connection and you should not fit 15mm gas to it ..some smaller output boilers can have 15mm gas ..but its always worth cheacking the instructions ..hope this helps

Razor

heating-eng wrote: »

been fitting boilers for years mate you havnt got a clue most boilers state 22mm ...

yes i am on the reg thanks. it means that sometimes you are better to get somebody in to see the problem as its not always that easy on a chat room to be 100% correct ..


how it is normally worded is ..gas supply should not be smaller than boiler inlet ..ie ..most combi boilers have a 22mm gas connection and you should not fit 15mm gas to it ..some smaller output boilers can have 15mm gas ..but its always worth cheacking the instructions ..hope this helps

You have failed to answer the question of whether 22mm is big enough.

It is not normally worded like that, Vaillant have a 15mm gas inlet valve so perhaps I should've installed a 937 on 15mm? Mmmmm

WB have a note similar to yours in the MIs but they also go on to say that 22mm is not always needed.

Once again no manufacturer state an absolute pipesize, they specify a minimum inlet working pressure.

I find some of the information you post worrying imprecise, you seem to put up incorrect information and then nit pick with the real RGIs to hide your inadequacies.

I suppose that you're covered by your statement that people should consult a professional after getting your advice

heating-eng

Razor wrote: »

You have failed to answer the question of whether 22mm is big enough.

It is not normally worded like that, Vaillant have a 15mm gas inlet valve so perhaps I should've installed a 937 on 15mm? Mmmmm

WB have a note similar to yours in the MIs but they also go on to say that 22mm is not always needed.

Once again no manufacturer state an absolute pipesize, they specify a minimum inlet working pressure.

I find some of the information you post worrying imprecise, you seem to put up incorrect information and then nit pick with the real RGIs to hide your inadequacies.

I suppose that you're covered by your statement that people should consult a professional after getting your advice

would 22mm be big enough will depend on a lot of thing ..elbows/ tees / lenth of pipe /also man instructions ...
i dont need to hide anything or try and attack people but i am here to help people ..i have spent many years going around picking up the pieces from plumbers that havnt got a clue what they are doing with gas.
please show me one post or comment where i am wrong ??????????

the 937 has a 15mm inlet ??

why dont we get back to the topic and help with the question ..

Razor

heating-eng wrote: »

would 22mm be big enough will depend on a lot of thing ..elbows/ tees / lenth of pipe /also man instructions ...

please show me one post or comment where i am wrong ??????????

the 937 has a 15mm inlet ??

why dont we get back to the topic and help with the question ..

I gave you the information you needed 25 metres of 22mm pipe will not supply 37kW as I hope you well know.

I've just shown you that you were wrong on this thread but you seem reluctant to admit it.

From the 831 down Vaillants have 15mm gas inlet valves.

My aim is not to chastise anyone but posting incorrect information is not 'helping the OP' is it?