Meter accuracy

FranklinD

I finally got around to clocking my gas meter for my new boiler, by timing the 1/2 ft dial for 2 revolutions. I came up with 78,127. The boiler is a Burnham ESC4, with an input rating of 91k on the sticker.

The formula I used was:
3600 / 47 (seconds) x 1020 (btu content) = 78,127.

I know the meter is pretty old (25 years at least), and the needle was a little jerky going around, but to be at 91k it would have to make the 2 revolutions in 40 seconds flat.

It would not shock me to find out that the installer didn't verify the manifold pressure per the install manual.

I don't believe it's piping related, as it's a 12 foot straight run to the boiler, 3/4" for 8 feet and 1/2" for the last 4 feet, with 1 elbow and 1 tee along the way. We have a power vented water heater as well (only have 2 gas appliances total).

It seems to fire and heat the house fine, but I'd just assume have it running as designed.

Does it hurt anything to have it under fired in this way, or am I destroying my one year old boiler?

Thanks for any opinions.

Gordy

Your sure the boiler was firing the whole time, and the water heater was off.

It's not unlikely to have a .5% margin but that's a lot.

FranklinD

Yep, I'm absolutely sure...and I just performed it again. Water heater was off, boiler running (and had been running a good ten minutes before I started the procedure). I read in the I&O manual that it has a step-opening gas valve but I believe that's only involved in the initial burner-on sequence. I'll check again to be sure.

When it ignites you can hear it start up, then about 10 seconds later it sounds like the draft inducer fan speeds up a little...I would assume that this is the second 'step' so to speak.

If I did have pressures checked at the gas valve and they were in spec, I would assume that the half-foot dial may be off a bit? I don't know. Our bill came today and for the period 10/24 to 11/24, we had 1144 degree days and I consumed 140 therms, which is down quite a bit from our old boiler. So I'll take it.

Mainly just don't want to be harming the boiler in any way.

Thanks for the input ;-)

BobC

My boiler is runs at 90,000 btu (set by orifice size) and I was having problems. When I checked the pressure before the boiler gas valve it was 8.3" wc, when the boiler started up that dropped to a little less than 5. the output of the gas valve was 3.5" and bouncing all over the place.

I had the gas company out and they verified the pressure drop was unacceptable. they replaced the pipe coming in from the main in the street with a new 1-1/4 feed and a new meter that connected to the 1" house main. Problem solved.

Note my internal main is 1" not 3/4", bigger is better. Its conceivable your meter is off but I would have the gas pressure checked at the input of your boiler gas valve and see if it drops excessively when it starts up, then check the output to make sure it's set correctly.

Bob.

Bob

BobC

If you call the gas company and tell them it appears your boiler is not drawing the correct amount of gas and you are concerned there might be a pressure problem, the will usually send someone out the same day.

Make sure they check the gas pressure when everything is off and again when everything is working. The pressure should not drop y more than 1/2 " WC at the meter. I doubt they will check the pressure at the boiler but at least you will know if the gas supply is good.

Bob

FranklinD

I've been thinking about doing just that. They're pretty good about checking everything here. At the very least I might end up with a new meter. They marked gas lines in the neighborhood last year for an alley paving project and they seem to run willy-nilly all over back yards.

We've never had an issue with our boiler or water heater when they're both running, and the old boiler was 133k input. But I do know the input of the water heater, so perhaps I should try clocking that to see if it too shows low by the same percentage. I'll post back tomorrow with what I find.

Thanks!

Tim McElwain

Does your meter have an AMR device (*automatic meter reading) if so the I/2 foot dial is sometimes not accurate. Use the next size dial.

FranklinD

I do wish it had an automatic reading device...but it does not. As it is, I email the gas/elec/water readings to the utility on the 24th of every month. They used to have an army of meter readers but not anymore...we're lucky if we get an actual read once every 3 months (probably to confirm my readings are accurate). Love those estimated bills! (Not).

I'm home sick today for the first time this year (one of my daughters seems to have a nasty stomach bug and demanded that Daddy stay home with her

captainco

Do you have a carbon monoxide alarm? Can you tell if a combustion test was performed on the boiler? Most likely the boiler is underfired and that will cost you money and possibly excess wear and tear. Just setting gas pressure at 3.5" verifies nothing except you have 3.5" of gas. I don't understand how people are still setting equipment with an eyeball and then writing your bill on an I-Pad!

FranklinD

Oh yes, brand new good quality CO alarms, one in the basement about 3 feet from the boiler and water heater, and the other in our back room at the basement door.

Both have the digital displays on them and have never changed from '0'. In fact, I take the one at the head of the stairs out to the garage with me anytime I run the little propane salamander heater (just in case). When I've done that I actually HAVE seen the display change. So I assume they're working (the installer supplied one as part of the boiler replacement, I bought the other).

The wear and tear is what I'm more concerned about than anything. I did call the utility and they will verify gas pressure output at the meter but would charge a service call to check pressure at the boiler gas valve. If the meter pressure is good, I'll be calling the installing company back to check it. I'd have no issue paying the service charge to the utility for the work, but I'm still covered under the installers labor warranty so might as well exercise it. Better safe than sorry.

FranklinD

I suspect a combustion test was performed, but I didn't see it actually done. I only say 'suspect' because during the initial fire up, the tech went to the van, got a little hard case, came back, and shortly after I spied what almost looked like a digital voltmeter on the basement steps...except that it had a long flexible tube coming off of it. That's about all I can say, unfortunately.

The invoice SAYS it was done, and I'd like to believe that, but the I&O manual also says to clock the gas meter to verify input btu's.

icesailor

Anyone with a digital combustion analyzer should have a printer to go with it. To give it to the customer and have a hard copy for yourself. So, if there's an issue after you leave, you have proof that it is running properly when you left.

FranklinD

So....I gave it a few more go's using the 2 foot dial, and come up with 89,900. Much better. The utility did send a technician over to look at the meter and he was quite unhappy to find that this meter had not been replaced when we bought the house 4 years ago...apparently that's how they've been doing their change-outs to a newer style, when someone buys a property and opens a new utility account for that address. Somehow mine got overlooked.

Sounds like I'll be getting a new meter, a new meter post and hanger, a new pipe from the meter to ground level (looks like some kind of poly poking out where it connects to black iron), and a new shut main shut off/lock out.

And...he says it won't cost me anything, which is VERY good news with the holidays and all.

According to him, however, they still won't be remotely read meters. They've gone to that in a few other areas around here but they don't predict changing to that anytime soon.

He did say that when they change the meter, he can and will check pressures and combustion readings on the boiler 'to verify the new meter is working properly', which sounds good to me since he'll be here anyway. I honestly don't have anything bad to say about SWL&P.