Best underground gas pipe after meter.

[MikeSharp01]

Am trying to source a length of gas pipe to carry the gas supply from the meter, in its box in the utilities building, under the garden and into the house. I understand I cannot use the plastic pipe as its beyond the meter but I am wondering what the alternatives are to this pipe system as it works out rather costly for a 25m run although I can get away with the smallest ID pipe as I am running the smallest boiler there is (11Kw I think) for DHW only! Any thoughts or ideas?

[PeterW]

Put the boiler in the utilities building (!!??!) and run the hot water pipes instead ..?

[Alexphd1]

Its been a while since i run in gas pipe outside but i believe you can use plastic. something like:-

https://www.plastics-express.co.uk/gas-service-pipe-fittings/gas-mains/gas-pipe-20mm-x-50m-coil-p-pw382?kw=pla-88869316890&fl=1000&ci=43648358370&network=pla&gclid=CMqroZ2zrtACFcFAGwodXnAG2Q

 

another option is keep a eye on ebay for a cutting of flexible stainless gas pipe ie tracpipe or gastite etc but fittings for this can be expensive aswell.

Edited November 16, 2016 by Alexphd1

[MikeSharp01]

7 hours ago, PeterW said:

Put the boiler in the utilities building (!!??!) and run the hot water pipes instead ..?

Has merits but the run is so long that even with very small bore pipework it will take a long time to get HW to the bathrooms / kitchen and the flow won't OK for 2 showers so have to stick with boiler in the house somewhere.

[PeterW]

Ah ok - hadn't realized it was a combi

[MikeSharp01]

1 hour ago, PeterW said:

Ah ok - hadn't realized it was a combi

Actually it might not be a Combi as I am struggling to get a one that can deal with 2 showers at once so might have to go back to a thermal store and a tiny boiler for just the air battery, the three towel rails and one radiator.

[joe90]

I have just run an external gas pipe ( LPG) and used the yellow plastic like above. Buried directly in the ground surrounded by sand.

[PeterW]

I think the issue is that yellow gas pipe is only rated for before a meter. 

 

I've asked the question of a friendly BG fitter ...

 

[Edited]

... who has said you can use 20mm yellow poly for the interconnector buried to the correct depth, and you should then terminate with an isolating valve and then continue with copper in the building.

[Alexphd1]

I believe you can use the plastic pipe between the meter and the appliance, tbh nobody even gas safe registered engineers should be running in/altering pipes etc before the meter only the gas network people (in our area they are a company called scotia network). 

[Nickfromwales]

10 hours ago, MikeSharp01 said:

Actually it might not be a Combi as I am struggling to get a one that can deal with 2 showers at once so might have to go back to a thermal store and a tiny boiler for just the air battery, the three towel rails and one radiator.

Have you seen the Vaillant 938 ? It's a hi-flow heat store Combi and as long as you have VERY good cold mains, or have taken measures to provide it, you'll get two adequate, or one blasting shower out of that with ease. 

[MikeSharp01]

28 minutes ago, Nickfromwales said:

Have you seen the Vaillant 938 ? It's a hi-flow heat store Combi and as long as you have VERY good cold mains, or have taken measures to provide it, you'll get two adequate, or one blasting shower out of that with ease. 

That would solve part of the problem, the local water supply is excellent I measured it at over 50L minute on a 25mm pipe, I am still thinking that I will put a SUNAMPPV in line with it so I can get the PV excess stored but not clear how we control the two working together although the sunamp does say it works with combi boilers. I guess you just wind the output temp down from the boiler and recover it from the sunamp but as the sun amp wilts I guess you need the combi to work harder or can you line them up the other way around and deliver the output from the sunamp at the input to the combi? 

 

PS does the size of the boiler affect the SAP calculation, must check that!

Edited November 17, 2016 by MikeSharp01

[Nickfromwales]

SAP should go against its lowest kw output ( e.g. when fully modulating). Is that the case? If so, iirc, the Vaillant will go down to 9kw. 

[MikeSharp01]

Just now, Nickfromwales said:

SAP should go against its lowest kw output ( e.g. when fully modulating). Is that the case?

Not sure just looking through the manual on the trail SAP software I have (From Energy Design Tools) to see what effect it has. I guess its like all of life, its about optimising the compromises!

[Nickfromwales]

Good luck with your nighttime reading ?

[MikeSharp01]

Nick, if you are still out there, is that boiler classed as a 'storage combi boiler' I wonder. Looks like only the efficiency is taken into account and heat losses from storage combi but still reading (page 24 of 234)!

[Nickfromwales]

Quote from the link,

"The ecoTEC plus 938 is a 38kW high efficiency storage combination boiler which has been designed especially for larger homes which have a higher hot water demand."