re route gas pipe

[Agile]

The pipe size depends on the load of the gas appliances.

But if the total length will only be 4 m then I would expect that 22 mm will probably be adequate.

But the total gas pipe run includes vertical pipes as well as horizontal. The number of elbows are also relevant as they have greater flow resistance,

Tony

 

[hippo4x4]

The pipe size depends on the load of the gas appliances.

But if the total length will only be 4 m then I would expect that 22 mm will probably be adequate.

But the total gas pipe run includes vertical pipes as well as horizontal. The number of elbows are also relevant as they have greater flow resistance,

Tony

at the moment the run is 43ft of 22mm to boiler with 7 elbows before t's off to 15mm (1ft) then 4ft of 22mm plus 1ft of 15mm to hob,
new run will be 13 ft of 22mm with 3 bends no elbows 2 straight joints joining to boiler then the 4ft of 22mm plus 1ft of 15mm to hob.

at the moment if hobs on and run hot tap the gas flow dips slightly on hob, gas man said new run will stop that.

main point was to find out trench depth as i wanted this trench dug whilst door was out so even if 32 mm pipe trench size wouldn't been much bigger i just needed to know if pipe could be put under screed and how deep needed.

i can do diy pluming myself and have for years without leaks but with gas i wouldn't take risk myself especially when i want it buried. digging i can do

 

[rules&rulers]

Has your gas installer thought about using "tracpipe" http://www.dbsaltd.co.uk/downloads/TracPipe CSST/Information Sheets/IS 001 Buried TracPipe.pdf

Edit,pipe needs to be sized correctly.your gas installer will know all about that.

 

[Agile]

at the moment if hobs on and run hot tap the gas flow dips slightly on hob, gas man said new run will stop that.

The permissible pressure loss is only 1 mbar in a nominal 20 mbar.

A 5% reduction in pressure would not normally be noticeable in a hob flame size.

Sounds as if your gas pipework is currently somewhat undersized.

Tony

 

[J_N30]

Wasn't there mention of the lease holder being informed of the works?

 

[J_N30]

Wrong thread. Sorry

 

[hippo4x4]

Has your gas installer thought about using "tracpipe" http://www.dbsaltd.co.uk/downloads/TracPipe CSST/Information Sheets/IS 001 Buried TracPipe.pdf

Edit,pipe needs to be sized correctly.your gas installer will know all about that.

thanks for the link, yes he mentioned this but said cost wise go for copper and wrap he said used same at his under concrete so if good enough for him

 

[hippo4x4]

at the moment if hobs on and run hot tap the gas flow dips slightly on hob, gas man said new run will stop that.

The permissible pressure loss is only 1 mbar in a nominal 20 mbar.

A 5% reduction in pressure would not normally be noticeable in a hob flame size.

Sounds as if your gas pipework is currently somewhat undersized.

Tony

its only running 2 items on the current 22mm setup was linked into warm air heating before boiler installed but as said is an ex council flat and im not convinced of quality of work plus put it down to length of run before hitting any appliance.
my last place had same boiler running 3 bed house plus gas cooker with no drop issues this was 22mm pipe to boiler approx 9 ft then 8 ft run of 15mm to cooker.

so once all the excess pipe removed should be ok.

cheers