steam heat - open all radiators?

jkelly

Hi - My husband and I bought a 100 year old house - it ended up being our first time living outside the south (now in Illinois) in an old house that is big (7,000 sq ft including the apartment over the carriage house on the same system. Our experience: Year 1 - fun, snowy, surprisingly AWFUL gas bills.  Year 2 - energy audit, insulation, some changes, better but stil expensive.  Year 3 - about to face winter and wondering if efforts we make are worth it.

Question1: it is just the two of us in the house -we close off bedrooms and "turn off" those radiators (we appaear to have a 1 pipe system with knobs on the end that say Honeywell and have numbers 1-7 and a red button).  Does this help or is it less efficient since the massive boiler still has to heat up steam to get to the rooms we do use.

Question 2: we rent out our carriage house apartment - their utilities are part of ours. I'm pretty sure the tenants aren't as thrifty with the thermostat/energy as we try to be.  Do our efforts of keeping the thermostat lower go unnoticed because the boiler stil fires up to send heat to the apartment or is it helpful (on energy costs) for us to keep ours at a lower temp?

we love our home but would love to get a grip on this and understand if there is anything else we can do.

thanks in advance!

moneypitfeeder

to start

I would recommend that you take pictures of your boiler from all sides, a pic of a radiator, and anything unusual attached to the piping, either in the basement or attic. Then while the pros weigh in on your system order the steamy deal here, so you'll better understand what they are getting at.

http://www.heatinghelp.com/products/Super-Deals/14/129/A-Steamy-Deal



To verify that your boiler is sized appropriately is a good place to start after getting some books on steam heat. You'll have to do some math, and a little research to find the correct table to use to calculate how much radiation all your rads together put out. That info allows you to eliminate a major expensive overhaul if you find that it was sized correctly for your system. (And the pros will probably ask) The most common tables, and the equation are all found in the Lost Art of Steam Heating. Greening Steam is also a good reference, but I recommend reading Lost Art first.



Then what I'm guessing without seeing anything is that if your venting needs upgraded or replaced, and possible piping issues near the boiler that are costing you in efficiency.



Are the pipes in the basement insulated?



There are plenty of ways you can make your system more efficient, welcome aboard!

Dee

nicholas bonham-carter

big house big bills

is there an additional thermostat for the apartment? 1-pipe steam supply valves must never be turned off, however you may have thermostatic radiator vents, which will do a moderately good job of keeping rooms from over heating.

by all means take some pictures of the steam supply pipes around the boiler, and we can look for any obvious causes of inefficiency.

probably near to the boiler, on a return pipe, should be mounted the main air vents whose purpose is to allow the air to escape as the steam is rising, so take pictures of those as well. a picture of the pressure gauge, and pressuretrol as the boiler is steaming would help.

when properly installed, and maintained, your steam heating system should be slightly cheaper to run than a hot air furnace.--nbc

moneypitfeeder

am I mistaken

But I thought with 1 pipe, you could turn the radiators full off with no problem, either by turning the supply shut completely, or turning the air vent upside down, (so it would not work, and that steam couldn't enter) with no problems. The only time problems would be induced would be if you closed it at the supply valve and the valve didn't shut all the way, thereby letting steam enter without a clear path for the condensate to leave.

nicholas bonham-carter

valves off or on?

our valves are old enough so that i would not trust them. i just use the upside down vent method to turn off the radiators. the problem is worse when people try to throttle the radiator by closing the supply part way.

congratulations ms. moneypitfeeder on your excellent piping job-you will be an inspiration to all of the old and new visitors to the wall!--nbc

moneypitfeeder

That makes

complete sense, the old valves are hard to trust. And thanks for the kudos, I'll be skimming and cleaning the boiler this weekend. She's run for a week now under 1/2 PSI with no hammering or water feed issues. To the original poster, I hope you put up pics, so we can see what you're working with.

Jamie Hall

The simplest way

and the most reliable way to turn off a radiator with one pipe steam is to turn the vent upside down -- as everyone has said, in principle you should be able to turn off the valve, but older valves rarely shut off completely and on one pipe steam this causes problems.  Turning the vent upside down prevents it from opening, and if the vent can't open to let the air out the steam can't get in (much) and for all practical purposes the radiator is turned off.



I might note, though, that if the room in which the radiator is off can get below freezing, this really isn't such a good idea after all, as what little steam does get up there will condense -- and freeze.  Which isn't good for the radiator or the valve or your budget.  If that were a possibility, than I'd look into thermostatically controlled vents.



And yes, turning off some of the radiators does have an effect on the boiler.  What will happen is that it will build some pressure more rapidly, and tend to cycle more on pressure towards the end of a heating cycle.  This does reduce the efficiency somewhat -- but you'd save more from not heating the rooms than you'll lose on efficiency, so I wouldn't worry about it.



There is a very important caution on turning the heat off in rooms which you don't use.  Be sure that the temperature in these rooms stays above the dewpoint of the air.  Otherwise, you will get condensation on surfaces in these rooms.  Sometimes this isn't a problem, but often it is: books, for instance, will mildew, and plaster may be damaged (sometimes enough to require replacement).  Wallpaper can peel.  Etc.  So do be careful about condensation.



Do your tenants have their own thermostat? 

The Steam Whisperer (Formerly Boilerpro)

Ideas.....

First, listen to Jamie about potential plaster damage.  I have been in many buildings in Chicago where this has occurred.....Hyde Park, Kenwood, Beverly, et el. 

Also, most boilers are grossly over sized for the job they need to do, so closing off many radiators may reach the point of not being beneficial because the boiler efficiency can get very low.  That said, the gas input to the boiler may be able to be reduced to improve operation of the system and potentially, overall efficiency.

Improving efficiency of a steam system is usually relatively easy, but requires a complete look at the whole system and some re engineering, as nearly all older steam systems were designed to run with coal boilers, and now are running on gas.  Coal boilers and gas boilers operated the system much differently, so changes need to be made to the system accordingly. 

jkelly

pics and more info

first - thank you!

The boiler is underground in a tunnel that connects the carriage house to the house underground.  So, I took a pic of all of the pipes in the tunnel and then some of the boiler. 

we may not be truly turning off the radiators because none of the rooms get near freezing - just chillier than the rest of the house.  and, we open them up periodically when we have guests.  when i say "off" i mean turning those knobs (pic included) to 0 which seems to keep them from putting out heat except for one that is broken. but regardless, not worried about plaster freezing yet, it doesn't get that cold (although we did have the ones in the garage downstairs disconnected and because we were heating that for no reason and we just keep an eye on it when it gets below freezing to make sure the pipes don't freeze).

Yes - the renters have their own thermostat.  If we never turned our heat on, they could still turn on theirs.  We have 3 thermostats in our house but it is my understanding (from the heating people who have serviced our boiler) that only one controls the heat, the others are for air. So, we are able to keep that one lower becuase it is near a window in the kitchen and the rest of the house iswarmer than what the temp says.

I feel pretty confident that the boiler is appropriate but that's only because it was put in fairly recently (within the last 10 years I think) and it was done by a guy who owned his own heating and air company that was living here at the time.  But, that's all I'm basing it on.

I think i've addressed all the questions and thanks again!

jkelly

radiator pics

Wasn't sure I could load all of the pics at once so here are radiator pictures.

thank you!

nicholas bonham-carter

old vapor system

it must be fun to have your own tunnel!

your system looks to be an old vapor system, with some sort of outdoor reset thermostatic control. these systems were the best of their day, but they run on surprisingly low pressures, maybe 2 ounces, so the first addition you should make should be a 0-2 psi gauge, and if you want more economy and comfort, a 0-16 ounce vaporstat.

next the traps should be checked, along with the trv's. increasing the capacity of the air to leave the system without burning extra fuel to squeeze it out would be the next step. post some details of the control system as well as improvements have been made to those controls in recent years. make sure the thermostat is not in a room with a trv on the radiator or they will not play nice!

let's see some pictures of the piping around the boiler.

i suggest also that you get the books from the shop here, "a steamy deal"--nbc

Dave in QCA

2-pipe Vapor Systems

You've got a great old system and it looks on the surface to be in good shape and indicate good work.  The near boiler piping appears from what we can see to be precisely correct.  The boiler feed pump set up is good, although a vapor system might work fine without it depending on the time it takes for condensate to come back, but with it, you know that your boiler water level will be kept precisely where it needs to be.  It appears that the end of main drips return to the tank via F&T traps and the condensate piping also returns to the tank.  This all appears good.  In the steam piping, the only thing that I see that is lacking is the main vents appear to be too small.  Hoffman 75 vents are probably not big enough to provide for even distribution of steam.  Would have to know how long your steam mains are and what size of pipe to recommend a proper vent.



You thermostat situation needs to be figured out.  First, lets forget about the cooling thermostats, they have nothing to do with the heat.  But you indicate there is a heat thermostat in both the garage and the house.  When you look at your steam mains, do you see any kind of electrically operated zone valves where the garage main and house main separate from each other?



If you do, the thermostats must be operating the zone valves, and if that is the case, and end switch on the zone valve should be activating the boiler burner.



If you don't have zone valves, the I would guess that the two thermostats are connect in parallel and which ever one is calling for heat is going to fire the boiler, sending steam throughout the entire system.  I would not do it this way, but if that is the way it is, I would certainly put a lock on the garage thermostat so it can't be turned up to a rediculous temp.



The next thing in the picture is your radiator valves.  They are actually self contained thermostatic valves.  That means that you can turn a valve to a lower set point and as the room cools down, the valve will open.  Then the valve will modulate to maintain that arbitrary temperature.  This is a great way to control rooms at lower temperatures in distant parts of the house.  55 is probably the coldest you want to go to prevent causing damage to the building, as has been mentioned in earlier posts.  However, if there are valves on radiators on the first floor that are in rooms that are where the thermostat is located, or connected to rooms where it is located, it would be a good idea to leave those valves in the full open position.  Otherwise, your main thermostat could be operating the boiler to heat the house, but the steam would not be able to enter the radiators because of closed or partially closed radiator valves.



I think its safe to say yes, you can turn down your unused rooms and bedrooms with any problem.  Make sure you keep the doors to those areas closed.



The next thing I would do is get a good handle on how the two thermostats operate.  What exactly do they operate?  A zone valve, or only the main burner?

The Steam Whisperer (Formerly Boilerpro)

boiler size, et el.

that looks like a Weil Mclain LGB- 7 or 8, which is probably way too much boiler for your home. Something about 1/2 that capacity is probably more appropriate, so that is definitely not helping the fuel bills.    Also, the boiler piping in general looks much better than most, but the header( horizontal pipe) looks rather low.  On a boiler this small, however, it probably is having rather little effect on performance.  Also, it is likely the condensate pump or feed tank is not needed.  Vapor systems rarely need them.

nicholas bonham-carter

a light at the end of the tunnel

are the supply/return pipes insulated in the tunnel?

and as boilerpro [the chicago expert] says, there may be an oversize problem with your boiler. this can be checked by doing a radiation survey to find out if the boiler is over-sized or not. the burner could be down-fired, to match the needed edr.--nbc