new gas connection

[jacob]

I have a new gas supply. Is there anything I need to know about connecting up to the meter (other than that it should be done by a corgi)? The plumbing is obviously simple.

cheers

Jacob

[tarquinlinbin]

Do you have the internal supply correctly earthed with an earth connection adjacent to the supply on the meter outlet?

[ski]

Obviously!

[andrewpreece]

I fitted my own combi last month and did the gas bit. I'm no expert but I was careful to keep the gas pipe earthed to the meter before connection to avoid a possible static discharge from the pipe to meter when the two are brought together. To be honest I reckon just holding the two your a bare hands, one on each side will discharge any static safely, but temporarily earthing the gas pipe with a jump lead would be certain.

I used solder joints for the new gas run, but the connection to the meter was a large compression nut; the joint had a tacky sealant smeared around it that I guess is best for gas tightness.

You are talking about the pipe that comes out of the meter to your domestic appliances aren't you? I believe the main gas pipe entering your property, and the regulator and meter are gas company property.

When you connect up and turn the gas on, test the joints for leaks with soapy water or somesuch; I had access to the industry aerosol spray stuff but I imagine soapy water will work. I have heard that squeezy can cause corrosion so wipe it off after.

Then you're supposed to do a pressure test with a u-tube manometer ( clear pipe in the form of a U half-filled with water ) fitted to the gas meter at the purge nipple, after the gas pipes have been filled with gas to regulator pressure (20mBar), and the main valve turned off. This is another leak test, and there are limits to the allowable change in pressure in a given period of minutes, then it needs repeating at 10mbar to check that a main gas valve leakpast hadn't masked a gas pipe leak of exactly the same magnitude etc. Ed Sirret gives a very useful explanation on his webpage ( Google it, though I think it is in the UK.D-I-Y faq's ).

Note the mains gas pressure is maybe 27mbar, and the regulator only regulates with a minimum gas flow, which confused me, though not with the tests detailed here.

Finally, there's the business of purging the new pipe after all is proved; I purged some unused spurs as well in case there was an air/gas mixture lurking in them.

Of course I am not an expert so you must DYOR regarding what is necessary to do the job competently.

Andy.

[jacob]

Thanks for the info. My new meter has a plain brass fitting on the outlet - you can't get it off the meter bracket but you can remove the meter entirely, which I presume is what one is supposed to do when soldering, or solder etc could drop into the meter.

cheers

Jacob

[Toby]

Not sure you should mess about with the meter. All my gas pipes are soldered, except for the meter connection. I believe you should have a demountable joint at this junction, such as a compression fitting as others have stated.

[Ed Sirett]

It's not just about static sparks which would be unlikely to make more than a damp squib of a flame even on a gapping 28mm pipe.[1] It is about protecting YOURSELF from a faulty electrical installation which is using the gas pipe (inadvertently) as part of the circuit. This is an unlikely but nevertheless possible occurence. For instance there might be a large earth leakage on a duel fuel cooker which also has missing earth so that when switched on the gas pipe - earth clamp - earth connection on supply wire... is now part of the circuit.

The meter should have had nice springy neopreme (sp?) sealing washer. either that was completely life expired or missing.

[1]Not if the gas were on though!

[Ed Sirett]

Some meters will have various devices fitted to discourage tampering. You can obtain (somtimes Transco leave them behind) thin dished discs which can fit into the meter outlet to block off the meter. Removing the meter is bad because you may get dirt into it. You may leave the work area unattended once the meter is blocked off whci might be useful.

[Ed Sirett]

Pleae read the FAQ. Gas pipes can be soldered, threaded, back-nut and long screw or compression (if accessible).