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Dom Perkins

Gas Engineer
Mar 29, 2013
30
6
8
37
Kent
Member Type
Heating Engineer (Has GSR)
Hello, It's that time of year again when everyones put their heating on and you watch the Operating pressure struggle to get to where you want it..
I'm after a bit of advise regarding what people have left on safely with regards to operating pressure.. I have just fitted a 34cdi.. I didn't check the op pressure of the old Worcester 34CDi I took out (1990's job) but having come to commission the new install tonight had only 12mb standing and didnt even bother with operating... called the gas board out and he did the usual cv..bridge the meter, but nothing worked... checking next door they were rocking along at 15.2 working (so he said) and similar up and down the road.... so there is a problem in the road..and he clearly looked worried he was going to have to start shutting people off...dont envy that job tbh... point is, he seemed to think if he could get me to 15 like the rest it's all good.... it's not, as mentioned in TECHNICAL BULLETIN TB 0040 a (2010/09) - 15mb is for only a short time and shouldn't be left like that...
I cant commission a 34cdi on that even if he does get me 15mb.. 14mb on 34cdi isn't accetable is it..
So whats the score? I dont do loads of this sort of work, and rarely have a problem like this which isn't fixed by CV swap or meter/ blockage.. the pressures are usually good in this area...
any advice appreciated....
 
Hello, It's that time of year again when everyones put their heating on and you watch the Operating pressure struggle to get to where you want it..
I'm after a bit of advise regarding what people have left on safely with regards to operating pressure.. I have just fitted a 34cdi.. I didn't check the op pressure of the old Worcester 34CDi I took out (1990's job) but having come to commission the new install tonight had only 12mb standing and didnt even bother with operating... called the gas board out and he did the usual cv..bridge the meter, but nothing worked... checking next door they were rocking along at 15.2 working (so he said) and similar up and down the road.. so there is a problem in the road..and he clearly looked worried he was going to have to start shutting people off...dont envy that job tbh... point is, he seemed to think if he could get me to 15 like the rest it's all good.. it's not, as mentioned in TECHNICAL BULLETIN TB 0040 a (2010/09) - 15mb is for only a short time and shouldn't be left like that...
I cant commission a 34cdi on that even if he does get me 15mb.. 14mb on 34cdi isn't accetable is it..
So whats the score? I dont do loads of this sort of work, and rarely have a problem like this which isn't fixed by CV swap or meter/ blockage.. the pressures are usually good in this area...
any advice appreciated..


An update to this if its of any interest. The gas main in the road was flooded and had caused similar working pressure throughout the entire street, 6 homes were shut off over that really cold night yesterday including my customers. The water was pumped out and for now the pressure is back up to 20mb standing, 18.5 operating at meter, with boiler under full load reading 16.5mb gas valve - right on the limit for this make and model. Come full load on the gas mains in the area, i imagine it will drop back down again under what the manufacturer requires, but not a lot i can do about that. everyone in the few roads effected are in the same boat and are just being left on for now.
 
I had one a couple of yrs back - did a tight test & got a static of 55mb! Called Transco out who confirmed my digital gauge hadn't gone mental, he the went up & down the street & got similar reading elsewhere. He was on the verge of shutting off the whole street when he went round the corner & saw a Centrica van at the sub-station. Apparently they were 'adjusting' the regulator at the sub. So all kinds of weird things can happen around this time of year - I wouldn't stress too much about it for now. Maybe pop back in a week or 2 to put your mind at rest.
 
I had one a couple of yrs back - did a tight test & got a static of 55mb! Called Transco out who confirmed my digital gauge hadn't gone mental, he the went up & down the street & got similar reading elsewhere. He was on the verge of shutting off the whole street when he went round the corner & saw a Centrica van at the sub-station. Apparently they were 'adjusting' the regulator at the sub. So all kinds of weird things can happen around this time of year - I wouldn't stress too much about it for now. Maybe pop back in a week or 2 to put your mind at rest.

Just what I did Sid, cheers!
 
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