Does it need purging?

[fireman -Sam]

First off I'm not a gas engineer but a fire engineer. I've just had a bit of a problem on a job where the main incoming solenoid valve had been left off but the heaters on the site where then turned on or well where tried to be. They called in a Gas company who found the problem.
But they are now saying that the hole system needs purging with nitrogen as there will be air in the system. Is this correct as I cant understand how air has got into the system? Surely the heaters/burners would just shut of if the pressure was to low and wouldn't let air into the system.

Any advice would be appreciated thanks.

 

[ShaunCorbs]

wont need purging with nitrogen unless they need to work on it

but depending on volume yes it might need to be purged but not with nitrogen

no they would try and fire till they locked out (eg fault)

where are you located just for reference?

 

[fireman -Sam]

Thanks for the reply.
That was my thoughts don't understand the nitrogen bit, I can understand the possible purging with gas bit and also pressure testing after.
Its a big pipe around 12-18 inch and over 150+ meter long so will be a fair volume.
Its around the Birmingham area.

 

[ShaunCorbs]

Thanks for the reply.
That was my thoughts don't understand the nitrogen bit, I can understand the possible purging with gas bit and also pressure testing after.
Its a big pipe around 12-18 inch and over 150+ meter long so will be a fair volume.
Its around the Birmingham area.

yep air to gas purging unless there working on it doesnt matter on size they will have to be commercially gas safe to up1 spec

whats it supplying just air heaters?

 

[fireman -Sam]

Yeah just air heaters all of which have a auto cut off from the fire alarm themselves sadly the main valve relay had a issue and remain closed.
I will recommend to the customer to ask why the company are saying it needs purging with nitrogen and tell them to possibly get a second opinion. Thanks again.

 

[ShaunCorbs]

Yeah just air heaters all of which have a auto cut off from the fire alarm themselves sadly the main valve relay had a issue and remain closed.
I will recommend to the customer to ask why the company are saying it needs purging with nitrogen and tell them to possibly get a second opinion. Thanks again.

yea best option if you dont mind me asking wheres the cutomer located / site location

manchester ?

 

[fireman -Sam]

No I am based in the Manchester area but this site is in Coventry we look after a number of there sites most of which are in the north west area.

 

[ShaunCorbs]

No I am based in the Manchester area but this site is in Coventry we look after a number of there sites most of which are in the north west area.

Nice little patch

Any other questions/ updates just post away

 

[king of pipes]

The gas pipework will only need purging with nitrogen if work needs doing on the system ie decommissioning like changing the solenoid valve. If its a power failure and the heating was switched on then it will need testing and then air to gas purging and recommissioning. Cheers kop

 

[fireman -Sam]

Just a quick up date, the gas company carried out a air to gas purge although I still don't get how air would as got into the system, I would have though the valves would just shut once the pressure dropped.
Anyway it took the gas company about 5 hours for 2 men, think there is 8 heaters in total and a few need a cheery picker to get up to them. Although I think the building owners supplied that. The bill came to around £2.5k in total which I thought was crazy.