What difference does keeping one radiator off do in single pipe steam system?

bipbap

We have a 3-story multifamily building with a single pipe steam system.

There has always been one big old 36” wide and 39” tall radiator in the front lobby. My Dad has kept it turned fully off for decades because he’s old school and says no sense heating the lobby, and he thinks it saves money to keep it off.  It’s on its own riser as well.

Does that make any sense?
Will it save any money to keep it off in the scheme of a 3-story building with about 20 other radiators working?
Would it have any impact to the greater system to turn it back on? I just don’t want to turn it back on and then something on the 3rd floor starts acting up.

Thanks for the advice.

ethicalpaul

The cost is probably negligible although I suppose it could be up to a 5% increase?

throw a small vent on it like a Maid o mist #4 and see what happens!

Does your system currently cycle on pressure?

bipbap

Yes it is a vaporstat set to keep it under 1lb.

5% is actually significant, since sometimes the winter gas bill can be as high as $800 a month.

bipbap

Wait sorry, the system cycles when the thermostat temperature gets under 68 degrees. Is that what you meant?

ethicalpaul

I meant anytime. If you open that radiator, the cycling will be reduced somewhat. That’s why I asked.

the 5% was the roughest of estimates because you have 20 other radiators (of unknown size)

bipbap

So if we don’t really need the heat in the hallway, then would you say it actually makes sense to just turn it off since it won’t affect the greater system to turn it off and it can only be costing some amount more to keep it on?
Could my Dad be right again....?

bburd

Yes, he could be.

bucksnort

bburd said:

Yes, he could be.

https://www.ispot.tv/ad/wlFY/progressive-group-session

nicholas bonham-carter

What sort of control is on the system?
Is the thermostat sensing the hall radiator?—NBC

bipbap

No the thermostat is not sensing the hallway, it’s inside an apartment far from the hall.

dabrakeman

Steam will get to the other radiators faster if that radiator is closed off which is directionally good UNLESS your boiler on cold days or recoveries is cycling on pressure (radiators are getting full of steam on longer cycles causing system pressure to rise reaching the set pressure cutout point of the vaporstat or pressuretrol). In that case having the radiator shut off would hasten the rise of pressure vs having it open causing you to operate at higher pressure longer which would eliminate any savings and add stress on the system. I have 2 of 13 radiators closed which is a bigger percentile but manage still to keep my pressure from ever exceeding a couple oz even on the coldest days by restriction of my cycle time to not exceed 30 minutes.

ethicalpaul

If you want the lobby cold, he’s right.

bipbap

Yeah a cold lobby doesn’t really affect anyone so if it saves some money and doesn’t mess with the system I guess we will keep it shut off.