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Colin W
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March 7, 2023
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Would anyone kindly help with converting a very old imperial meter reading to kwh please?

  • March 7, 2023
  • 75 replies
  • 3809 views

Hello, I have a very old imperial meter made by Parkinson Cowan (Ser/ No S512290) that works in ft2. Would someone kindly help with the conversion to kwh please. I also would like to know if it measures in ft2 or 100ft2. This is an image, many thanks.

 

Best answer by BPLightlog

Updated on 20/07/26 by Ben_OVO

Ok so it’s measuring in cubic feet (ft3) the reading on the dial is 4974 (ignore the Red figure) and the calculations are like this (posted on your bill)

So the extra piece to understand is the x 2.83 along with the others to get kWh. 
If the previous reading was 4874 for example the difference is 100 so the calculation would be:

100 x 2.83 x calorific value (typically 39) x 1.02264

The result is then divided by 3.6 to get kwh

Remember that the calorific value varies so that figure can change (and does).

 

The calculation above is shown on your monthly statements, which can be viewed on your app and online account by following the guide below:

 

 

If you’ve got an imperial gas meter then it may be old, and may have reached the end of it’s certification. We’d recommend upgrading to a smart meter free of charge. Smart meters send reads to us automatically so you don’t have to, meaning your bills won’t be to estimated readings. You can find out more, and book an appointment, here.

 

 

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enadwalker
Newcomer
March 24, 2026

 

​@Firedog  but why is the each unit of the black dial charged as the 100s if the red dial is the single ft3 which does increment relative to the proving wheel which is correlated to the.071ft3/rev on the face plate, should it not be charged as

(black digits 10000,1000,100,10.) which I submit to EDF?

BPLightlog
Super User
BPLightlogSuper User
Super User
March 24, 2026

 

​@Firedog  but why is the each unit of the black dial charged as the 100s if the red dial is the single ft3 which does increment relative to the proving wheel which is correlated to the.071ft3/rev on the face plate, should it not be charged as

(black digits 10000,1000,100,10.) which I submit to EDF?

As has been mentioned elsewhere, the red dial is not single ft3. That is shown by the ‘clock’ style dial, which turns once every single unit - hence the painted on 0 after the red figure. 

 

NB- this should really be with the main thread so that others can follow the full details

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Ben_OVO
Community Manager
Ben_OVO
Community Manager
March 24, 2026

Hi ​@enadwalker and thanks for your post. Just to let you know I’ve edited the screenshot of the email you sent in so that it doesn’t include your email address anymore. 

 

It sounds as if your billing is correct now, but that doesn’t explain why so many bills were reversed and re-billed. Definitely one for the complaints team as you say, and please do keep us updated as to how you get on. I’d recommend just getting back in touch with them and asking why so many bills were reversed.

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Firedog
Super User
FiredogSuper User
Super User
March 25, 2026

​@Firedog  but why is the each unit of the black dial charged as the 10s if the red dial is the single ft3 which does increment relative to the proving wheel which is correlated to the.071ft3/rev on the face plate
  

The text underneath the picture of an imperial meter explains how the black digits represent hundreds of cubic feet. I think you’re chasing a red herring by concentrating on the standard ‘0.071 ft³/rev’ marking. That is referring to (possibly virtual) revolutions of the metering mechanism, not the clock dial which rotates one turn per ft³. 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
    Ben_OVO
    Community Manager
    Ben_OVO
    Community Manager
    March 25, 2026

    ​@enadwalker just to let you know I’ve merged the thread you made about this same subject into this thread, to avoid confusion. It’s always best if we do this, as means that these useful threads can be seen by others having the same issues in future.

     

    I’m hoping the info given to you by ​@Firedog and ​@BPLightlog has answered your concerns about the meter? 

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