Purging gas pipes?

[Harry Stottle]

I have just had a combi boiler installed and now need to remove a gas fire. The gas fire supply will be blanked off at the main gas pipe running through the house, not at the fire itself, and there is a gas cooker also fed from a branch off this main pipe. After the feed to the gas fire has been blanked off, I can easily purge the air from the pipe to the gas cooker, but this will leave about a 3 metre feed to the boiler unpurged, and I don't really want to disturb any boiler connections. My question is, will the boiler self purge itself through its starting process, or is there anything else I should be aware of before restarting the boiler?

[A.Lee]

I worried about this too when I fitted my boiler, but it didnt seem to be a problem at all, the boiler lit far faster than I woudl have expected - the pipe is maybe 4 metres long from meter to boiler.

The gas hob on the other hand took far longer than expected. I had done neither before, so had no prior knowledge of how long they take. Alan.

[Ed Sirett]

If your just capping a gas fire then you won't get any air into the rest of the pipe work.

[TheScullster]

"Ed Sirett" wrote

Are you assuming that he will use a compression blank rather than a soldered cap here?

Phil

[Harry Stottle]

Thanks for the replies, and even more reassuring, the lack of warnings :-)

[Ed Sirett]

If the joint remains accessible and it's done right it makes no difference to me.

[Harry Stottle]

Soldered cap, now done and tested with no problems, thanks again.

[A.Lee]

Does the gas burn off when you try to solder a joint without first purging it out? or would you always try to purge out the gas before capping a pipe? Ta Alan.

[Ed Sirett]

You obviously have to turn off the gas. 8-).

You have put the cap on the end and it is already more or less gas tight with the flux. The soldering process will not set light to gas which has little or no oxygen in it and which is inside the pipe.

However you should not solder any gas pipes within in 2m of the meter. Disconnecting the meter etc is a more advanced topic.