Uneven heating and regulator problems - 1920s steam building

joecoopowner

<span> </span><span>I'm an owner in a 1920's-era 8-unit coop apartment building that has a single pipe steam radiator system heated by a gas boiler. The system is regulated by a Heat-Timer device, installed in 1990, attached to a temperature-sensing device installed outside.</span>

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<span>The main problem is that the building heats unevenly. The four apartments on the side that share a common wall with another building are hot when the other four are cold. Since we're a coop, we need to insure that the people in the coldest apartments get the heat they want. And, as a result, people in the warmer apartments inevitably open their windows to keep things comfortable. </span>

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<span>The other problem is that the regulator seems to require constant adjusting. We'll set it to "B", until we hit a cold snap, and then we'll have to move it up to "C" or "D" and then back down again.  My guess is that this partly because the sensor is placed outside and the relationship between the outside temperature and the heating needs of the coldest apartments aren't always in synch.</span>

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<span>Here are my questions:</span>

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<span>1. Is it possible to balance the heating needs of the building better? What would we need to do? Would we save money doing so? And if so, how much?</span>

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<span>2. Should we replace the Heat-Timer device with a programmable thermostat that takes the temperature from a remote sensor placed in the apartment that's the coldest? Would we save money doing so? And if so, how much? Should we set up a system that averages temperatures from the three coldest apartments? </span>

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<span>(Heat-Timer tells us the unit needs to be replaced, and wants to install a new version of the same electro-mechanical system for $3000, or a digital system for $5000. My understanding is that Heat-Timer systems were designed for landlords who wanted to control heat without having a thermostat that tenants could manipulate. Since we're a coop, we don't have that problem. The owner of the coldest apartment happens to be the coop president and doesn't open windows or do anything else to manipulate the system.)</span>

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<span>3. Since the radiators haven't been inspected for several years, should we hire a plumber come in and check the valves and the pitch of the radiators? Would that save us money? How much and why?</span>

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<span>4. Some of our coop members think all this is unnecessary and that nothing needs to be done. They say it’s inevitable that buildings heat unevenly, and the Heat-Timer will always need adjusting. They also say that the radiators clearly don't need any kind of inspection since they heat up properly. I certainly don't want to spend money unnecessarily. Do they have a point?</span>

Jamie Hall

Take a look at some of these...

It certainly should be possible to heat that building more evenly, although you may have to do a good bit of fiddling with vents.  The real problem is that you have uneven heat loss between the sides of the building (nothing like a party wall to mess things up).  If the radiation is the same in all the apartments, it may not be possible to get all the way just by venting -- but you can probably help.  First, make sure that the mains are thoroughly vented; it's almost impossible to over vent a steam main.  Having done that, it's time to attack the radiators.  What you need to do is slow the venting on the radiators in the apartments which are too warm.  Do this first!  Then, if that doesn't get you far enough, you can try speeding up the venting on the cold apartments, but do this with some caution, as it is possible to overvent a radiator.  You'll know if you do -- they get noisy.  None of this is all that expensive.



If that doesn't cure the problem, my inclination would be to junk the Heat-Timer and place a good programmable thermostat (Honeywell VisionPro, or something like that) in the coldest apartment; use that to control the boiler.  Then in all the other apartments you can install Thermostatically Controlled Vents -- Danfoss makes them, among others.  What these do is sense the local temperature and, when it reaches the set point, close the vent -- thus shutting off the heat to the radiator.  That will work.  It will also give your various members control over their own heat, which they might really like.  This isn't all that expensive, either.  If, for some reason, you don't want the occupant of the coldest apartment to have control of the boiler, you could also place a remote sensor in that apartment (or possibly a hallway?) and the thermostat itself in, for instance, the boiler room.  Even if you don't need to go with the TRVents, you can still junk the Heat-Timer, and go with the thermostat options as you like.



Anyway, that's my approach to this...

patrick linhardt

yes you can

Hi Joe,

Get a contractor that knows steam and fix the system and it will be cheaper to operate.

A balanced system saves money and is more comfortable.

Use a cycle rate control like a Tekmar or Heat-Timer to control the burner and install thermostatic vent valves like a Tunstall/Taco #5413 on all the radiators that overheat or all of them ideally. They control the flow of steam into the radiator by controlling the rate of air venting. They naturally balance out the system, give everybody control and save money. What a concept.

I can't help you with the people that want to do nothing, except waste energy.

Patrick Linhardt, Linhardt's Field Guide to Steam Heating

crash2009

If I was you,

I would get a steam pro in there for a consultation.  The cost would not be much if you divide it 8 ways.  There will likely be some resistance from the warm people, but I am sure you will have all the votes from the cold ones. 

1-It likely is possible to have balance back again, Has it been this way for 20 years or more?  or has something changed recently?

2 and 3 -I would not run out and spend any $$ on run and gun troubleshooting. 

4- Get a consultation, you will then have the facts,  then you can decide cooperativly, on wether or not anything needs to be done.

Good luck swaying the vote! 

The Steam Whisperer (Formerly Boilerpro)

Yes improvements can be made.....

The items listed above are good starts to getting the building heating evenly.    Anytime you can eliminate overheating you will save fuel.  Just think about it, if units are overheating and have to be ventilated or the space is a lot warmer than necessary,it is just like it being colder outside.    Overheating can impact fuel usage tremendously.  I recently worked with a 15 units Coop that had both under and overheating, depending on the unit.  With some work, the cold units are now warm and the overheated units are much cooler.  The preliminary numbers indicate a 20% savings in fuel bills and now everyone is much more comfortable.  We haven't even  installed any TRV's yet to take care of the final overheating issues..Which are related to the boiler being much too big for the building.

I also worked on another structure with similar complaints, though not as extreme  After an evaluation of the system, we made some simple changes, improvements, and tuning.  Virtually all the imbalance problems disappeared, and as a bonus the fuel usage dropped 40%.   An adjacent similarly constructed building owned by the same company next door had been converted to "high efficiency" hot air heat.   The steam heated building now uses about 30% less fuel per square foot than the hot air building.

There is really no reason to tolerate overheating in a steam heated building.  Individual radiator by radiator temperature control is exceptionally easy to install and will provide premium comfort and minimum fuel usage.

A review by a true Steam Professional may seem expensive at first, but can have great benefits.   The problems you are describing almost always lead to higher fuel bills, so fixing them should yield lower ongoing costs and better comfort.

FJL

Where Are You?

In what city do you live?

nicholas bonham-carter

overheating coop

one point to remember is that the heating system must have been working very evenly, when it was first installed so many years ago. the owners at that time would not have tolerated the conditions you describe. this should be your goal to return the level of comfort to its original condition. also of importance at that time would have been the economy of running. wanting to get more heat out of the fuel is not a modern invention! i am sure that your heating dollars are being wasted now.

i suspect that a good pro could check the pressure, and lower it to the most economical possible; and correct the main venting.

i would not replace the heat-timer until all other system deficiencies have been corrected, as these controls cannot compensate for a poorly maintained system. 

during the time of these corrections, the balance of the system could be changed so that the radiators on each floor will receive steam all at the same time, and it will have been time, and money well spent.

please give us some more information about your building: location,no. of floors, square footage of the floors, and current average winter gas bill. if you know the boiler ratings from a plate on the boiler, that would be useful as well.--nbc

p.s.  i didn't answer your question as to how much you will save in fuel cost. here is my experience--55 radiators, 1,050,000 btu, 1-pipe steam. had to replace leaking boiler, then reduced pressure range to 2-8 ounces with a vaporstat. installed extremely generous venting on the returns. our fuel use in the 2 subsequent years [corrected for degree days] has been been cut by one third. i am guessing that since you will not be replacing your boiler, that your savings may be in the 15 to 25 % range.

even more important in our case, along with high fuel use, we had no comfort, and plenty of noise. now we have evenness of heat, and silence. the gas company changed our meter, thinking the lower fuel use came from a faulty meter!!--nbc