Inexpensive Hourmeter for Gas Valve?

Captain Who

Has anybody ever installed an inexpensive hourmeter on their gas valve? It seems to me there's a lot of us in the same boat where we are contemplating taking the plunge into expensive vaporstats, expanding main venting, etc. and it would be nice to have an established baseline dataset to compare to. I'm thinking mount it under your thermostat and keep a spreadsheet daily where you note the hours of operation for the day, thermostat setting, outside temperature and wind conditions, etc.. It would be really nice to see those efficiency gains show up on a short term basis and to be able to quantify them easily.

Thanks.

KC_Jones

Just a suggestion and maybe you don't have this data. My gas supplier actually puts my past 13 months usage on every bill, they also put the average temp for that month and the same month the previous year. You can also look up online degree days for your area. I don't disagree with what you are doing just suggesting an alternative method that probably wouldn't cost anything except time.

Captain Who

Thanks KC. I'm actually thinking much shorter term than that. When you make a change to your system you want to know sooner than that what the effect may be. When you are talking the whole month, you can run into problems where you had different thermostat settings, different venting, pressuretrol or vaporstat settings etc..

Reading the gas meter doesn't isolate the boiler because it includes all the other usage like hot water heater, cooking range/oven, outdoor grill etc.. What would really help though would be to have the avg temp. data for the day and windspeed, or "degree hours" for the day (is there such a thing?). I'm still thinking I want the convenience of an hourmeter though. I believe they may only be around $25.

Thoughts on how to hook one up etc.?

vaporvac

MarkS did this a couple of years ago. If he reads this he can respond and point you to the most recent post where I asked him about it.. Meanwhile, I'll try to find it. I was interested myself as it seemed a fairly simple retrofit supplying useful info, especially as the newer Honeywell Tstats don't even provide boiler "on" time anymore.

Captain Who

Thanks vaporvac. I'm really anxious to try this and I appreciate you're interest. Yeah I guess I'm an engineering nerd type but I'm also cheap (lol) and want to know if my investment is paying off and how long it'll take to pay off .

KC_Jones

Now the question is what would be the ROI on the hour meter?

Captain Who

My White Rodgers 1F97-1277 doesn't have a "boiler on" time either. But even if it did it would be wrong because it doesn't subtract the time that the circuit is interrupted to the gas valve by pressuretrol cut-out to cut-in time, Cyclegard testing time, etc.

vaporvac

Darned if I can find that original post. It's an EMN meter, though. Someone else referenced it in this post: http://forum.heatinghelp.com/discussion/comment/1323358#Comment_1323358, but I'm not sure that's what marks has. He put it on both his installs and reports on the results from time to time.

Captain Who

Thanks for the help and answer. Your answer pretty much did answer my question but I just have a few additional questions. Please see my PM because for some reason it was no longer letting me post to this thread (?) I guess the moral is to not make the thread a question.

Captain Who

For anyone who might be interested in a LCD model, I found this one which is available online from Digi-Key for $30 not including shipping:

http://www.digikey.com/product-detail/en/701ZR001N1248D2060A/267-1057-ND/1679650

It isn't backlit and only has 5mm high digits and tenths display but is resettable to Zero and can be wired to power so that it is on continuously.

Captain Who

Thanks so much MarkS for taking the time and you DID answer my question but I think the overbearing thread algorithm won't let me post further unless I "reject" (!?) your answer.

You've brought up some thought provoking issues.

1) I guess it's only the pure engineer in me that want's a hundredth hour meter and I was pretty sure that it's overkill. I haven't found any that were digital and hundredth yet anyway, and I'm leaning towards digital so I can reset it to zero should I wish to. Maybe I wouldn't reset it though, on the other hand because that would add up some error over the course of a month, say.

2) If there are any pros out there that could reassure me that hooking up the sense terminal of a digital LCD hourmeter to a 24V AC gas valve would cause no harm, I'd greatly appreciate it. I feel like it might not be very much current drain but I'm not sure how much it is and how much would be too much, for that matter. Perhaps it's no different from applying a voltmeter, which wouldn't present any problems at all since there is no current drain.

Captain Who

Here's the datasheet for the one above I mentioned:
http://www.centuryfuelproducts.com/media/Forms/model700.pdf

Does this one look like it would work for 24 VAC gas valves?:

701FR001N1248D2060A - It wouldn't be backlit and would only have 5mm high digits but would be resettable and continuous operation and should be compatible with 12 - 48 VDC or 20 - 60 VAC.

If you wanted a nice backlit one with 7mm high digits I bet it will be quite a bit more expensive but this one should work:

701SR601N1248D2060A

Captain Who

OK now it is letting me post again so here it is:

@ MarkS - thanks so much for the reply. It's great to know that this can be done so inexpensively too. It brings up a few questions in my mind:

1) I guess that you find the 0.1 hour resolution to be satisfactory, especially with an analog meter where you can kind of tell where it is in between the tenths readings? Or would you prefer a hundreths resolution? I guess that's a bit of a disadvantage of a LCD model where you can't estimate between the final digits.

2) So the way you wired yours up it starts counting time from the moment the thermostat relay is energized to the time it stops calling for heat? I guess that wouldn't be too bad but wouldn't it be better to hook it up to the gas valve itself so that it counts the time that the gas valve is on? I hope that is doable because my system turns the burner off to check the water level and the pressuretrol also shuts the burner off when it cycles on pressure. Both of these things happen while the thermostat is still calling for heat.

3) Does the analog one make some noise, like a motor noise? I have my thermostat located near my computer and would probably prefer for it to be quiet there. I know computers put off heat but I have a remote temperature sensor too so that's taken care of. I suppose if I got the analog one I might just mount it in the basement right on the boiler but I might more easily forget to go down and check it every day.

4) Thanks a lot for that one on ebay. I found a datasheet for a Curtis Model 701 that looks like it can be compatible with 24VAC if you order the correct one and they have a model that can be backlit and be on continuously. You can also get one that you could hook a switch up to that allows reset to 0. This might be more expensive than the one you found on ebay, at around $38 or so.

Does your analog one allow resetting of the counter to 0? I'm not sure how important that really is to me.

Here's the datasheet:
http://www.centuryfuelproducts.com/media/Forms/model700.pdf

Does this one look like it would work for 24 VAC gas valves?:

701FR001N1248D2060A - It wouldn't be backlit and would only have 5mm high digits but would be resettable and continuous operation and should be compatible with 12 - 48 VDC or 20 - 60 VAC.

If you wanted a nice backlit one with 7mm high digits I bet it will be quite a bit more expensive but this one should work:

701SR601N1248D2060A

Captain Who

Here's the datasheet for the one above I mentioned:
http://www.centuryfuelproducts.com/media/Forms/model700.pdf

Does this one look like it would work for 24 VAC gas valves?:

701FR001N1248D2060A - It wouldn't be backlit and would only have 5mm high digits but would be resettable and continuous operation and should be compatible with 12 - 48 VDC or 20 - 60 VAC.

If you wanted a nice backlit one with 7mm high digits I bet it will be quite a bit more expensive but this one should work:

701SR601N1248D2060A

Captain Who

MarkS said:

1) 2a) If you are at all conscientious about checking your boiler water level, you should consider replacing the CycleGard LWCO with the equivalent SafGard model. Every time the LWCO stops the boiler mid-cycle to check the water level, it can take several minutes to rebuild the head of steam. Wasteful, and IMO unnecessary if the boiler is looked after properly.

I have a love hate relationship with that CycleGard, but I guess I consider removing it to not really be the low hanging fruit as far as improving my efficiency goes. I already swapped out an almost brand new 120V AC CycleGard (CG450) for a new 24V AC one (CG400) and an isolation relay when the former was only about a year old because I needed to have all the controls to be 24V in order for my new digital thermostat to work properly and to be able to power it with 24V which I needed to do in order to be able to add a remote temp sensor to it (White Rodgers 1F97-1277). So I'm not real anxious to buy another one just yet. I don't think it is too much of a problem since I have the "SmartCycle" feature activated. When the optional SmartCycle feature is activated, the CycleGard's test time sequencing is restarted each time the burner fires. This feature enables a full burner run cycle (10 or 20 minutes, depending on model) prior to the first Intermittent Level Test (since burner firing). My model is 10 minutes, but the way it plays out is that it only interrupts the burner a couple of times during recovery from a deep overnight setback of 8deg (daytime 61F, nightime 53F). I kind of like the protection it gives from the probe possibly misreading a low water level as OK, due to heavy foaming that can occur in the boiler. The SmartCycle is activated by connecting a wire to the hot leg of the gas burner valve. I wonder how many people don't read the instructions and don't even know that it exists.

I have to keep a close eye on my water level, since the knucklehead who installed it before I bought the house plumbed the top of the close nipple for the Hartford Loop 1/8" below the NWL (yep 1/8).

Captain Who

Wow, I see the thread got all messed up from when I was trying to post last night and it wasn't posting it. Oh well.

If anyone is still at all interested in this topic, I have found another model that I believe is suitable for what I want to do and I like that it is a low power draw LCD model that has larger digits at 7mm (instead of 5mm). I still wish I could find one with hundredths of an hour. It retails for $33:

ENM T44B65C round case, 3 holes, resettable, 4.5 to 60 V AC/DC

ENM T44G65C rectangular case, 2 holes, resettable, 4.5 to 60 V AC/DC

http://catalog.enmco.com/Asset/693.pdf

Captain Who

@ MarkS - that article on the Gifford Loop was very interesting but it doesn't apply to my particular system because I don't have wet returns and I don't have a water feeder. My LWCO (probe CycleGard) is actually located about 3" below the NWL. That is about where the top of the close nipple would be if the installers followed the middle of the mfg guideline of 2 to 4" below the NWL. I walk a thin line of trying to keep my water in the sight glass just a little bit above the top of the Hartford Loop (I aim for around 9/16") so as to not reduce my steam chest too much and keep the steam dry. If I get a leak in the returns or even if the bottom of a main gets a leak, I can easily lose enough condensate from the system that the water level drops below the top of the Hartford Loop and the resulting spitting of radiator vents on the 1st floor rads is not a fun thing. I have mounted empty cans to the varivalves so that hopefully it catches the condensate before it sprays on the carpet. That rusty water stains very badly. This will generally happen early in the morning when it is recovering from a overnight setback and you will come downstairs and there is no heat and the yellow light on the LWCO is on. Well before the yellow light came on though, the system was making a big mess of things with the condensate backing up in the rads.

Captain Who

Just ordered an ENM LCD Hour Meter and a separate ENM LCD Counter from Allied Electronics. They had to backorder the Hour Meter unfortunately, but it is in stock at ENM:

ENM Hour Meter #T44G65C $19

ENM Counter #C44G65C $16

I'll put them together on a panel and either mount them on the boiler or on the wall under (well under in case of any heat output which should be minimal) the thermostat. Unfortunately, they are not backlit but they have 7mm high digits and are resettable and can be powered from the power going to my thermostat. I'll post a picture when I get it all hooked up. I'll have to run a signal wire from the 24VAC gas valve on the boiler.