gas rate

[pauls]

i read on here and have heard aswell the percentage sum ie under and over 5% you can be under by 11% but over by 5% can i just get some clarifacation on this please.

 

[SimonJohns]

As long as you think it's close enough and operating safely

Would you cut an appliance off if it was 12% out?

 

[gasmarc]

sorry m8 new on me but look forward to the answer

 

[mikeygas]

I've been taught 10% under and 5% over.

 

[AWheating]

i dont think the figures are written in stone, but as you need to allow for discrepancy most are taught 5% over and 10% under. Where these figures are from i do not know.

 

[REDSAW]

i was told, 5% and 5%.

something to do with the 2 minute timing discrepency at the gas rate.

however, i will make that 10% below now as i had one last week that was bugging me.lol.

 

[CMairiD]

I was taught 5% +/- and that this figures came from BG and were rules of thumb (ie, you'll not find them in standards, etc).

 

[REDSAW]

i was told on my gas safe inspection last may if i remember correctly.

 

[gasmarc]

well I went to a 24kw combi today and did a gas rate and got 27 kw . I then checked the burner pressure and found it was 2 millibar over the maximum input burner pressure

 

[Rob Sale]

@gasmarc you sure it was not a zero governor valve? A zero governor won't give you a reading it will read b/tween -2 to 0 to 2 range on p2 burner pressure. What boiler was it.

 

[SimonJohns]

@gasmarc you sure it was not a zero governor valve? A zero governor won't give you a reading it will read b/tween -2 to 0 to 2 range on p2 burner pressure. What boiler was it.

Think you may have read gasmarc wrong. He said it was 2mB over the burner pressure according to mi. Not a zero governor giving strange readings

 

[Rob Sale]

that will teach me to scan read

 

[gasmarc]

it was a heatline C24 combi boiler , I presume it was a band B

 

[bert large]

Always thought it was 10% under. Not sure about the "over" figure but that would give much more cause for concern anyway.


I wonder how accurate gas meters are as they are never calibrated ?

 

[SimonJohns]

They should be calibrated to some extent. That's what they use to charge you for your consumption. If that was wrong I'm sure you'd have a fantastic case.

May have mine checked now lol £££££

 

[diamondgas]

i read on here and have heard aswell the percentage sum ie under and over 5% you can be under by 11% but over by 5% can i just get some clarifacation on this please.

New to me to pauls! As long as the appliance is burning correctly, fga passes and/or readings are withing manufacturers recomendations I wouldn't get to concerned! If in doubt give them a shout is a good motto to carry

 

[gasmarc]

As Bert pointed out more concern for over than under EG I was called to do a service on a ariston microgenus HE , When i looked at it I thought O boy do i really want to strip this thing down No. Well i managed to get FGA reading which was way out , Apparently the customers had had BG out twice because of their huge gas bills , The hot water was scalding hot the rads you could fry eggs on , this had been like this since they had moved in over 3 year ago , Who ever installed the boiler never checked the burner pressure which was way out , Customer delighted and my money doubled ,Happy Days

 

[Billy Bob Bob]

New to me to pauls! As long as the appliance is burning correctly, fga passes and/or readings are withing manufacturers recomendations I wouldn't get to concerned! If in doubt give them a shout is a good motto to carry

totally agree in all cases a fga will tell you strait away if gas rates out

 

[gasmarc]

flow rate and temperature rise and correct gas rate would confirm correct burner pressure , I think lol