gas rates!!!

[CXR100]

im currently using an app for doing gas rates, in collage we had to do them all on paper and work it out with a calculator, I cant seem to get my head around the maths in it anymore! got a landlord check to do this afternoon, not sure what the meter is but can somebody take the time to type the sums out and times etc so I can write it down and laminate it and put in my analyser box. my corgi book is in works van, and I cant find it on google anywhere. thanks

 

[Paulplumb]

Hi CXR100

Metric meter

time the last 3 digits of the meter for 2 minutes then subtract the first reading from the second reading eg. .356 from .436 giving .080

then multiple .080 x 30 (30 x 2 minutes gives 1 hour) = 2.4

Then multiple this my 10.76 (calorific value of gas) so 2.4 x 10.76 = 25.82kw gross

then divide 25.82 by 1.11 to get your NET figure =23.26 kw NET

With an imperial meter time the amount of time the needle takes to make on revolution then divide 3600 (amount of seconds in an hour) by that number. eg 3600/70 = 51.428

Take 51.428 then multiple that by 0.303 = 15.58ke gross then divide that by 1.11 again to get your net of 14.03kw net

There are some quicker ways explained here on the forum. I will try and post them up for you.

 

[ambrosia]

those apps are dangerous, makes people forget core stuff

imperial
time it
3600 / by time taken to do revolution x 1040 /3412 / 1.11

or metric
time it then x 30 then x 10.76 then / by 1.11

paul got there 1st and said it better

interesting enough how many different ways are there of doing it

 

[Paulplumb]

Some quicker ways.

Imperial: time the amount of time for one revolution eg 70 seconds and use this formula

1092/70(seconds) = 15.6 kw gross then divide 1.11 to get net


Metric is time the meter for 2 minutes deduct the first reading from the second and then multiple the result by 321

eg: .080 x 321 = 25.68 and then divide by 1.11 again to get net

 

[AWheating]

fek maths, use your app.

 

[Ermintrude]

Don't waste 2 mins of your life... Just copy from mi!

 

[stevetheplumber]

i dont think i could do it on paper as ive never needed to just carry the corgi book with the tables in it incase the phone doesnt work

 

[CXR100]

thanks guys, would rather use maths and a calculator to do it, went to do the landrord test , Worcester 28 si (2) at property, gas pipe run in 15 from meter (15meters away and few elbows) teeing off to gas hob, burner pressure only 10.4mb , mi states it should be getting 13mb, now got to go back to run new gas pipe in 22mm, gas pipe not sleeved, not earthed, flue not clipped it loft. gas turned ff, so I got to go back tomorrow to do the bloody thing now.

 

[CXR100]

just out of interest, the inlet pressure was fine, and high enough on the gas valve, but these gas valves have no adjustment on them , and it stated in the mi that they were factory set and had nothing in saying I could adjust them ect, so what are the chances that it is the gas valve that needs replacing rather than the pipe? the burner pressure was around 11.5mb without hob on , but was around 10mb with hob on, any helps - tips on this would be great as I do very little of these things now days.

 

[bassmonster]

Either way, the 15mm pipe is undersized...

 

[AlexGas]

Bad on maths!? Get one of these:

 

[AlexGas]

...so I got to go back tomorrow to do the bloody thing now.

Are you getting paid?

 

[CXR100]

nope, priced the landlord check at £120 inc a service as it was short notice so had to do it on a Saturday, its failed now so im charging him £250 for running a new gas pipe, 5 lengths of 22mm should do it, and its not that awkward, and installing clips to hold the flue, so ill me getting £370 for doing the job, I think its a fair price.

 

[firemant]

so are you nicking the pipes and brackets?

 

[CXR100]

where did you read that I was supplying them smartar*e ?? haha