Monitoring Actual Runtime

mikegcny

Background

• I have a single pipe steam system that was installed in 1927.
  
• I recently had a new Burnham Independence gas boiler installed with a Honeywell pressuretrol (pic attached).
  
• I replaced nearly all of my air vents and the system is now fairly well balanced.
  

I am monitoring my boiler runtime via Ecobee and using BeeStat for data analysis, and trying to determine if a 3 degree setback at night is worth it. The issue that I am having is that the Ecobee is only recording the data for when it is calling for heat, not the time the burner is actually running.

My understanding is that the pressuretrol will cut the burner when the desired steam pressure is achieved and then re-ignite the burner when pressure drops.

Does anyone know of a way to monitor the actual burner runtime?

Jamie Hall

Hook up something like this: https://www.grainger.com/product/3AE11?gucid=N:N:PS:Paid:MS:CSM-2295:TVRYAD:20501231&s_kwcid=AL!2966!10!79302424737062!4582901921276557&ef_id=7561167da5b41e54c47377e8b090f141:G:s&gclid=7561167da5b41e54c47377e8b090f141&gclsrc=3p.ds&msclkid=7561167da5b41e54c47377e8b090f141 to the burner.

ChrisJ

Jamie Hall said:

Hook up something like this: https://www.grainger.com/product/3AE11?gucid=N:N:PS:Paid:MS:CSM-2295:TVRYAD:20501231&s_kwcid=AL!2966!10!79302424737062!4582901921276557&ef_id=7561167da5b41e54c47377e8b090f141:G:s&gclid=7561167da5b41e54c47377e8b090f141&gclsrc=3p.ds&msclkid=7561167da5b41e54c47377e8b090f141 to the burner.

To the OP.

Close, but that's a 120V timer, so unless you want to use a relay you can likely find a 24V timer.

Just hook it up after the Pressuretrol so it's only counting when the circuit has 24V.


If your system is shutting off at over 2 PSI I'd avoid setbacks completely to be honest.

mikegcny

ChrisJ said:

If your system is shutting off at over 2 PSI I'd avoid setbacks completely to be honest.

Why is that - is it that running so low pressure its better to keep the water in the boiler as hot as possible and let the pressuretrol regulate shorter cycles?

KC_Jones

mikegcny said:

ChrisJ said:

If your system is shutting off at over 2 PSI I'd avoid setbacks completely to be honest.

Why is that - is it that running so low pressure its better to keep the water in the boiler as hot as possible and let the pressuretrol regulate shorter cycles?

I'll stick my neck out and go one step further. If you are able to get to the pressure that the pressurtrol is set at, I'd suggest that brand new boiler is oversized, or your venting isn't adequate, or both.

IMHO you shouldn't be hitting the cut out on a brand new install like you have. Especially when it's set that high. If that safety is being used as a control, then it should be set as low as it can possibly be.

mikegcny

KC_Jones said:

I'll stick my neck out and go one step further. If you are able to get to the pressure that the pressurtrol is set at, I'd suggest that brand new boiler is oversized, or your venting isn't adequate, or both.

I am not sure I am cutting off - that is what I want to monitor overnight. I do not think I am cutting off during the day.

For venting, I still need to replace the vents on the mains. The existing vents were tapped with 1/4 inch pipe/verticals, and my new Gorton #1 and #2 are made for 1/2 inch verticals. My understanding is that I want at least 1/2 pipe leading to the new vents. When the plumbers come back to replace my kitchen gas line, I am going to ask them to install the new vents.

JUGHNE

IMO, a 1/4" opening will handle the G2, even though the vent has 1/2" threads.

Certainly pass enough for a G1.

KC_Jones

According to the vent charts, a 1/8" pipe will flow enough to support a Gorton #2 vent.

Jamie Hall

Quarter inch is ample for a Gorton #2. In fact, it appears ample for two of them. Never have figured out why it has the larger threads...

Keeping the pressure low has all sorts of benefits. The steam moves faster, for one. The various widgets -- vents, controls, what have you -- last a lot longer. There is a potential for less water being pushed out of the boiler, though that shouldn't be an issue in a properly piped system.

Keeping the boiler water hot while cycling on pressure is a rather different issue. It's well worth while, but generally if it really is pressure that is the control there the off period will be short enough that the boiler stays plenty hot -- in fact, if may never actually come off the boil because of stored heat in the metal.

If you are not cycling on pressure on what might be called "normal" calls -- just keeping the structure at a constant temperature -- the boiler probably isn't too oversized. Pressure cycling coming out a setback is a different matter -- that will be a much longer call; perhaps an hour to an hour and a half -- and it isn't too surprising that a boiler will cycle on pressure, unless it is very closely sized.

mattmia2

You could put a 24vac hour meter across the terminals of the pressuretrol so it only runs when the pressuretrol is open. Ebay has really cheap chinese hour meters.

Jamie Hall

mattmia2 said:

You could put a 24vac hour meter across the terminals of the pressuretrol so it only runs when the pressuretrol is open. Ebay has really cheap chinese hour meters.

eh? I think we want burner run time, not total off time?

mattmia2

That would tell you if the burner is shutting off on pressure and for how long.

mikegcny

Jamie Hall said:

Quarter inch is ample for a Gorton #2. In fact, it appears ample for two of them. Never have figured out why it has the larger threads...

Thank you - that saves some work. Especially since the tap on the main for the #2 is on a difficult angle to access.

Jamie Hall said:

If you are not cycling on pressure on what might be called "normal" calls -- just keeping the structure at a constant temperature -- the boiler probably isn't too oversized. Pressure cycling coming out a setback is a different matter -- that will be a much longer call; perhaps an hour to an hour and a half -- and it isn't too surprising that a boiler will cycle on pressure, unless it is very closely sized.

Thank you for this insight.

The first thing I asked the plumbers who were giving me estimates was 'Did you read Dan Holohan's books?' The company I went with was the most expensive estimate that I got, but was the only plumber that walked the house with me and measured each radiator. So I don't think that I am that oversized unless he did the math wrong.

Last night's setback recovery took about 1:50; "normal" maintenance calls are like 40 minutes for me so far. I really want to meter the pressuretrol to confirm that it is pressure cycling. Since I just need to monitor the fact that voltage drops, I might be able to do this via the Ecobee. I have a Bosch heat pump at my other house and I can get lots of data out of that system.

Jakek

If you enjoy tinkering with electronics, you can use an Arduino or Raspberry Pi or some other cheap board with GPIO support. I run a wire from both sides of the relay on the vaporstat (or pressuretrol) and the common from the 24v transformer to a bridge rectifier (to get DC) and to a relay which is connected to a raspberry pi. This records the exact time there's a call for heat, when the pressure is reached/drops, and when the heating cycle ends. Separately I record the readings from the gas meter so I can see how much gas was used in the overall cycle. (Assuming nothing else using gas at the same time.)

It's all very interesting to see how much fuel it takes to bring system to full pressure, meet the desired set points, etc. (Big setback = less boiler runtime = less fuel)

Hot_water_fan

There has been some research on this topic by the Department of Energy. They found nightly setbacks did save energy, about 1% per degree setback.

https://www.nrel.gov/docs/fy14osti/61151.pdf

mikegcny

Jakek said:

If you enjoy tinkering with electronics, you can use an Arduino or Raspberry Pi or some other cheap board with GPIO support. I run a wire from both sides of the relay on the vaporstat (or pressuretrol) and the common from the 24v transformer to a bridge rectifier (to get DC) and to a relay which is connected to a raspberry pi. This records the exact time there's a call for heat, when the pressure is reached/drops, and when the heating cycle ends. Separately I record the readings from the gas meter so I can see how much gas was used in the overall cycle. (Assuming nothing else using gas at the same time.)

This seems like a good idea. I have no way to get info from my gas meter though.

I also have an autofill that would be nice to record.

Jakek

mikegcny said:

This seems like a good idea. I have no way to get info from my gas meter though.

This is the easy part.

I use this Software Defined Radio USB Stick stick from Amazon plus the RTLAMR (automatic meter read) package that someone kindly wrote. This lets me take the actual wireless readings from the gas and electric meters that the utility receives. Both meters ping about once a minute so it's easy to link with the boiler.

I have some simple linux (bash) scripts that take this data and put it into a database. Separately I have another one of the SDR sticks which reads the 433Mhz temperature pings from meters all around the house and outside.

I will say I've wasted a lot of time setting this stuff up but it's inexpensive and fun and records a lot of data.

mikegcny

Hot_water_fan said:

There has been some research on this topic by the Department of Energy. They found nightly setbacks did save energy, about 1% per degree setback.

Isn't this only for condensing boilers (hot water) and not steam?

Hot_water_fan

Isn't this only for condensing boilers (hot water) and not steam?

I think it's non-condensing as well. I don't know about steam vs. water. I've seen many similar studies in the ballpark of 1%/degree for 8 hours setback. Just to put the number in perspective.

Another option would be to setback for one billing cycle and not for one billing cycle and adjust for heating degree days.

offdutytech

If you need a set of dry run contacts you can buy a Functional Devices RIB1UC and parallel it off of the pressuretrol for your 24vac hot and then pick up a neutral off the boiler control transformer. This relay has isolated contacts to run to any monitoring system and provides a normally open or closed contact if you need it. 

Jamie Hall

KISS. Pick up a signal from the motor running the blower or burner pump, or, for gas, opening the gas valve... Use that to actuate a high impedance relay of the appropriate voltage, and take the contact closure for whatever you want.

mygardenshed

My thermostat has a setting for filter change time. Set this to its maximum and maybe that will track your heaters runtime.

mygardenshed

My thermostat is a ritetemp 8050.
From the instructions:

PRR

ChrisJ said:

...that's a 120V timer, so unless you want to use a relay you can likely find a 24V timer.....

Yes. 7 years ago I put this hour-meter on my gas furnace LV leads.

https://www.amazon.com/dp/B07CJR9VCY
https://www.amazon.com/kosiwun-Mechanical-Hourmeter-Motorcycle-Generator/dp/B08N6XCJZD
I thought I got it at Amazon but can't find the record; anyway today Amazon has several. I don't like LCD, mechanical is going out of style, but there is still stock.
The old-old meters would be specced 24V and either AC or DC. Today they are super tolerant; this is rated 6-80V AC/DC.
I have it tapped as "call for heat". On my gas furnace that gives 2min more at start and a minute less at shut-down. My furnace should "never" shut-down on heat or stack pressure, so the hours shown are accurate.

AdamInEvergreen

I have an Emporia Vue. It resides in my electrical panel and has little clamp sensors that detect amperage going through. One of the clamps has the circuit for the boiler, which includes the boiler, zone valves and both pumps but nothing else. After it is installed you can download from their app or website a CSV file showing consumption...1 minute intervals goes back a week, 15 minute intervals goes back a month

My boiler seems to have a few different consumption patterns over the last week:
-(35%) Firing and circulating / not firing and circulating (can't tell the difference based on electrical consumption)
-Short, low consumption periods...maybe just exercising the circs
-Off (50%)
-Balance (15%)...seems like not enough to run the circs but more than nothing? Some of this might be with the circs running on low because I've been messing with that lately....or maybe the Emporia Vue isn't quite precise enough do what I'm trying to do.

Patterns might be easier on 15 minute intervals because they would cut out a lot of noise.

If your plugs in to a normal outlet you could use a different smart plug with tracking. Installing the Emporia Vue I have required taking the cover off the panel, which exposes the mains & the bus bars. Definitely need to know how to work around electricity safely (turning things off, verifying lack of power with two devices, etc).

I have two circs that oversized, but I'm typically running them on medium and low. Looks like them combined with the boiler & zone valves they suck 0.25kW when going. If you have more modern high efficiency ones it might be hard to identify when they are on or off.