Master venting

Jay85

Is there anything I can reference to try and get my venting as efficient as possible? I have a 3 family house with a total of 10 radiators. The main in the basement is a 2" pipe 55 feet in length. I have 2 gorton#2 on the end. The risers going to the apartments are 1.25" and unvented. All the radiators have gorton vents as per the recommendation of the gorton rep using the chart they have. 

Jamie Hall

Are you having a problem with uneven or slow heat? What pressure does the boiler normally run at? What do you have it set for a cutoff?

EBEBRATT-Ed

@Jay85

venting the tops of the third floor risers may help. Tell us a little more about how the system runs. How long to get the third floor radiators hot?

Jay85

Jamie Hall said:

Are you having a problem with uneven or slow heat? What pressure does the boiler normally run at? What do you have it set for a cutoff?

I just recently purchased this 3 fam building that has been very neglected. I dont know much about how the system was operating since this is my first winter with it. I know most of the radiator vents were not functioning properly and most of the heating system was neglected. I am looking to make it as efficient as possible. I actually just put a new guage on 2 hours ago and the highest it read was 12 oz just as the set temp was reached. The pressuretrol is set at .5/1

Jay85

EBEBRATT-Ed said:

@Jay85 venting the tops of the third floor risers may help. Tell us a little more about how the system runs. How long to get the third floor radiators hot?

Im not exactly sure how long it takes to get the top floor hot since its difficult to get access since the tenant is rarely home. I feel like the boiler ususlly runs for 30min. Maybe an hour when its very cold outside. Im basically looking to get the heating system working as efficient as possible. 

nicholas bonham-carter

You could always put in an indoor/outdoor wireless thermometer sensor in each unit to see the temperature without entering the apartment. Some have a display for 3 sensors.
The Honeywell VisionPro thermostat has provision for remote sensors as well, with temperature averaging. These can be placed in the most exposed rooms in the building.
Setting a constant temperature with no setbacks would be best for comfort, and economy. You can see the efficiency of your main venting on the low pressure gauge-the lower the better, (2 ounces).—NBC

DanHolohan

This will help:
https://heatinghelp.com/systems-help-center/balancing-steam-systems-using-a-vent-capacity-chart/

jhewings

It sounds like your system is working well. If all of your radiators are heating up and there is little or no banging, and the pressure is less than 1psi a when the setpoint is reached, then that's good for 1 pipe steam.

Jay85

nicholas bonham-carter said:

You could always put in an indoor/outdoor wireless thermometer sensor in each unit to see the temperature without entering the apartment. Some have a display for 3 sensors. The Honeywell VisionPro thermostat has provision for remote sensors as well, with temperature averaging. These can be placed in the most exposed rooms in the building. Setting a constant temperature with no setbacks would be best for comfort, and economy. You can see the efficiency of your main venting on the low pressure gauge-the lower the better, (2 ounces).—NBC

Yes. Right now its at 12. I would like to get it lower. 

Jamie Hall

Lower than 12 ounces? On one pipe steam, this may simply not be possible. Those systems were typically designed for 16 ounces or so, and if it is running on 12 you are doing just fine.

ethicalpaul

What is your source for those design criteria of one pipe systems, Jamie? I'd like to read that. I would consider myself a failure if my 1 pipe system ran at 1 psi

DanHolohan

I don’t have Lost Art with me on my travels, Paul, but it’s in there. It has to do with system pressure drop and certain minimums on the pressuretrol/vaporstat settings. 

Jamie Hall

ethicalpaul said:

What is your source for those design criteria of one pipe systems, Jamie? I'd like to read that. I would consider myself a failure if my 1 pipe system ran at 1 psi

Lost Art. But I can't find it right now... Mind you, like most things like that, I expect most of the systems were over-designed, and will run quite happily most of the time at a lot less pressure drop than that.

cross_skier

I am with @ethicalpaul.  If Empire State Building can be heated with 2 psi @ 2.7 million square feet, then unless there is some nonlinear relationship, a 5,000 square foot building should only need 0.1" of water pressure to heat.  I'm probably confused 🤔

Chris_L

ethicalpaul said:

What is your source for those design criteria of one pipe systems, Jamie? I'd like to read that. I would consider myself a failure if my 1 pipe system ran at 1 psi

I agree. If you need 1 psi to fill the radiators in your home, I have to think your radiator vent are too small.

I couldn't run at 1 psi if I wanted too. The only time the pressure gets above a few inches of water is when all the vents are closed. And once they close, the pressure rises quickly. It doesn't matter if I turn off the boiler with a sensor at 10" of water or let the Pressuretrol do it. At most the boiler would run for a matter of seconds more before hitting 1 psi.

Here is a pressure plot of the most recent run of my oversized boiler. It was on for about 25 minutes and never got above more than about 1" of water before the thermostat was satisfied.


And here is the same plot for my tenant's (even more oversized boiler) which ran for about 21 minutes:

It ran at about 2" of water until all the radiator vents closed, at which point the pressure rises steeply.

I have a sensor on it that turns the boiler off for 15 minutes when the pressure reaches 10" of water, which it did. (The thermostat was satisfied after it was off for 5 minutes.) 10" of water is about 1/3 psi (or 6 oz.). If you look at how quickly the pressure rises (points are plotted every 15 seconds when the boiler is on), you can see how quickly it would reach 1 psi or an even greater cut-out point.

ethicalpaul

Nice Charts, Chris. That shows probably a typically-oversized boiler, as you said.

If it were more oversized, you'd see the pressure build even before the vents were closed--not a good scenario!

Mine is only very slightly oversized (because there was no smaller Peerless boiler available) and I have to be returning from a big setback before it will finally start to slowly creep up to a psi.

the idea that in the old days systems were designed to "run at" .5 or 1 psi is very confusing to me because if you install a boiler whose sq feet of steam matches the EDR, then as you said, there's no possible way to even get the pressure up that high under normal operating conditions--at least that I can think of.

cross_skier

My boiler EDR matches my radiators combined EDR.  I've got low pressures, under 1" H20, but my radiators do get hot and seem balanced.

All my radiators are next to solid masonry walls.  My third 1-1/2" main is Teed off my 2" second main.  This is not ideal and will be corrected with my new boiler. 

Jay85

I just went back to check on things. It is much much colder tonight and the pressure went all the way up to 3.3psi. It finally kicked off at 3.3 even though the pressuretrol is set to .5/1.  For you guys running very low psi, does the psi stay low even on nights with the temp in the teens? 

jhewings

If it is that gray pressuretroll with the white differential wheel inside...there have been a lot of complaints about that product and here is another: I had my boiler off for several hours and there was a several degree setback to heat up. The pressuretroll did not kick out at 1.5, 2, 2.5, I turned off the power switch when the pressure was 2.9 psi. I put in a Vaporstat and it reliably cuts out at 1.7 psi (which happens rarely). And cuts in at 0.7.

Jay85

jhewings said:

If it is that gray pressuretroll with the white differential wheel inside...there have been a lot of complaints about that product and here is another: I had my boiler off for several hours and there was a several degree setback to heat up. The pressuretroll did not kick out at 1.5, 2, 2.5, I turned off the power switch when the pressure was 2.9 psi. I put in a Vaporstat and it reliably cuts out at 1.7 psi (which happens rarely). And cuts in at 0.7.

I have been messing with the adjustment screw but seems there isnt enough tension on the spring to reset once the pressuretrol trips. 

ethicalpaul

Jay85 said:

I just went back to check on things. It is much much colder tonight and the pressure went all the way up to 3.3psi. It finally kicked off at 3.3 even though the pressuretrol is set to .5/1.  For you guys running very low psi, does the psi stay low even on nights with the temp in the teens? 

This is a little different issue I think.

On my system, it does stay low even when it gets cold out, down to zero or lower farenheit.

If your system gains pressure when it's very cold out, I would think that might be an issue of not enough radiation combined with being oversized (related issues to be sure). Was your system able to hold the thermostat's setting?

Here are the combinations I can imagine:

- boiler can't keep up on cold days but pressure doesn't build: This would be a boiler correctly sized for its radiation, but too little radiation to keep up with the heat loss of the building. Note that for a correctly-sized system it should have to run all day long just to keep up on the cold "design day". If I were building a system, I'd make it so that it couldn't quite keep up on design day.

- boiler can't keep up on cold days and builds pressure: If pressure builds significantly, the boiler is oversized, period. If you can't meet the thermostat, that means there is not enough radiation, just like in the case above. Maybe someone removed some radiators.

- boiler can keep up on cold days and pressure doesn't build: This boiler is sized correctly to its radiation and the radiation is at least good enough to keep up with the heat loss of the building. It could be that the radiation is too large for the building, that's how they used to make all of them after all.

- boiler can keep up on cold days and pressure builds: This boiler is oversized to its radiation, and the radiation is at least large enough to keep up with the heat loss. This is probably 80-90% of steam systems out there. Too much radiation and too much steam for that radiation, because contractors are afraid to tell their customers that on the coldest days it might get chilly.

Jay85

ethicalpaul said:

I just went back to check on things. It is much much colder tonight and the pressure went all the way up to 3.3psi. It finally kicked off at 3.3 even though the pressuretrol is set to .5/1.  For you guys running very low psi, does the psi stay low even on nights with the temp in the teens? 

This is a little different issue I think. On my system, it does stay low even when it gets cold out, down to zero or lower farenheit. If your system gains pressure when it's very cold out, I would think that might be an issue of not enough radiation combined with being oversized (related issues to be sure). Was your system able to hold the thermostat's setting? Here are the combinations I can imagine: - boiler can't keep up on cold days but pressure doesn't build: This would be a boiler correctly sized for its radiation, but too little radiation to keep up with the heat loss of the building. Note that for a correctly-sized system it should have to run all day long just to keep up on the cold "design day". If I were building a system, I'd make it so that it couldn't quite keep up on design day. - boiler can't keep up on cold days and builds pressure: If pressure builds significantly, the boiler is oversized, period. If you can't meet the thermostat, that means there is not enough radiation, just like in the case above. Maybe someone removed some radiators. - boiler can keep up on cold days and pressure doesn't build: This boiler is sized correctly to its radiation and the radiation is at least good enough to keep up with the heat loss of the building. It could be that the radiation is too large for the building, that's how they used to make all of them after all. - boiler can keep up on cold days and pressure builds: This boiler is oversized to its radiation, and the radiation is at least large enough to keep up with the heat loss. This is probably 80-90% of steam systems out there. Too much radiation and too much steam for that radiation, because contractors are afraid to tell their customers that on the coldest days it might get chilly.

Yes. I have no problem getting the apartments up to temp. I know because I can check through the smart thermostat. But also when you walk into the apartments you can feel its deff more than hot enough. 

neilc

have you checked your pigtail for clear and free breathing all the way back to the boiler?
is the gage mounted after the pigtail, with the Ptrol?

maybe post a picture of Ptrol, pigtail, gage, and sightglass,
all in one is ok

Jay85

neilc said:

have you checked your pigtail for clear and free breathing all the way back to the boiler? is the gage mounted after the pigtail, with the Ptrol? maybe post a picture of Ptrol, pigtail, gage, and sightglass, all in one is ok

Dont judge about the wiring to the ptrol. It is now the way it should be. I was just messing with it to see if it was clean and if it was working without the wire connected or not. Unplugged 1 wire and it shut everything off. Yes. I removed pigtail and it is clear. Also checked the elbows and they are clear as well.