Inequal heat distribution among apartments

Susan Scroggie

Thanks. I'll check into what we have. I believe that it is steam heat and all of the radiators seem to be the same in the whole house, but maybe they aren't.

The first two floors have an extension and that room is always cold. We recently did a renovation in our apartment (the garden level) and found that the walls of the extension in some places had no insulation and in other parts has less than required. My thought is that there isn't any insulation in the roof of this part leading to the warm air quickly escaping.

I'm thinking of having someone come in to do an analysis on our energy inefficiency so hopefully something will come of that. This has been a problem for years so it might be the insulation.

Any other ideas are welcome. Thanks.

Susan Scroggie

Inequal heat distribution among apartments

Hi -
I live in a brownstone in Brooklyn that has been divided into 5 apartment - one on each floor. All of the radiators are functioning fine, but we find that the bottom 2 floor cool down significantly quicker than the upper ones. There is often a 10 degree difference in temperature between the top and bottom stories.

A plumbing company has recommended that we install a Honeywell thermostat that has 4 sensors so as to take the readings from a lower apartment and an upper apartment to drive when the boiler comes on. They also recommended rebalancing the heaters.

I'm thinking that it might be more an insulation problem than a heating problem that we are having.

Any ideas as to how we should go forward or questions that we should ask the plumber would be greatly appreciated.

Thanks!

Brad White_203

What

kind of radiators do you have in those lower floors versus the upper floors?

By the way, is this hot water or steam? I am guessing HW but have no idea why.

My thinking is, if the lower floors are fin-tube baseboard (low mass, quick to heat but as quick to cool) and the upper floors have cast iron radiators, (high mass, long output), what you describe sounds like a textbook condition where radiation types are mixed.

What leads me to think this way also, is that you say that the radiators are 'working fine but that they cool down significantly more quickly'. Getting there is not the issue, staying there is, so I suspect a thermal mass issue in the radiation.


The solution if this is the case, would be to have those lower two floors on their own zones or run the entire building on constant circulation (if HW) and use thermostatic radiator valves and outdoor reset.

If all of the radiators are of similar types, I would want to know what the heat loss is and what capacity the radiators have relative to the heat loss. (Might the radiators be under-sized in other words.)

Now, unless something was done recently, meaning, if the radiators are as they were day-one, someone would have noted this condition generations ago and done something about it. (Or sit and kvetch, alone, cold and in the dahk..)

Insulation problem? That too would have been noted years ago. Tough to insulate those brownstones but might the upper floors be insulated (not the roof which is often done, but the walls)? Top floors with insulated walls and bottom floors not?

If we can eliminate the radiation (type and capacity) as an issue, we should look at the heat loss and in particular air infiltration.

Balancing is a flow function and I will go out on a limb here. Chances are the boiler is in the basement so the first floors have first dibs. Absent a total blockage, you would have as much if not more flow than upper floors. I am thus less concerned about that based only on experience. (I am in Boston, 215 miles away, what do you want?

Bottom line, I suspect a radiation type and size issue firstly. An IR scan and blower door test to check for leaks and insulation deficiencies would be high on my list regardless.

My $0.02

Brad