Steam Radiator Systems for a novice

DuckMan

Hello all. First time poster here. I'm inexperienced with steam radiators, so please forgive me if I sound clueless

My family and I moved into a condo in a 100 year old building in Connecticut five years ago. There are three units on each side of the building, and we're in one of the top floor units. The other five units have cast iron steam radiators and no air conditioning. Our unit is different as the previous owner removed the three radiators, stuck them in a storage compartment in the building's basement, capped the pipes off in the unit, and then installed a split system from Daikan for both heat and A/C.

Our building is self-managed, and the head of the condo association lives below us. Three years ago someone on the first floor was selling his unit, and when the new owners did a home inspection they found that the building's gas furnace was broken. We then replaced it, and have not heard of any heating issues during any winters since then.

Suddenly this winter the first gas bill came in at more than double what it was last winter. Next thing you know, the head of the condo association told my wife and me that "these systems are designed to fill all radiators in the building and by having removed your radiators you are causing the system to run ineffectively since it now builds up unnecessary pressure and short cycles." He is asking us to put the cast iron behemoths from storage back in. Nevermind that he himself approved the previous owner of our unit to remove them, and he's never said anything about this issue since we moved in.

Can someone possibly verify if what this guy is saying might be accurate or not?? He sometimes knows what he's talking about based on experience, but he also often just makes up "facts" that are completely wrong and even a simple Google search can debunk them. I have been in the room with him when he has argued with experienced contractors and claimed he knows what's he talking about because he has a degree in mechanical engineering (this is a lie, in reality he has a degree in American History and works in a bank).

Any answers/help at all is appreciated!! I've found some info on Google searches on how these systems work, but not how one radiator being capped might impact how well the whole system works. I'd think with the new furnace having been installed in 2015 would negate what he's saying, but I'm just not sure.

Happy New Year!

- Mike

Fred

If they sized the new boiler to include radiation in your apartment, yes, it can cause the boiler to short cycle because it is over-sized for the actual connected radiation. Will that burn more fuel, No. It just causes the boiler to shut down because the remaining radiators can't condense the steam as fast as the new boiler can make it. He should have known that your apartment did not have radiators by the time the new boiler was installed. If he wants to remedy the short cycling, he can have the boiler down-fired or he can have a two stage gas valve installed. Either of those options will resolve the short cycling, but to answer your question, the short cycling isn't causing enough effeciency loss to have an impact on the utility bill.
You might even want to ask him if he has looked at the other five units to see how many of those owners have radiators shut off or have TRV's on the radiators. Every one that is shut off, either by the supply valve or by a TRV or a combination of the two will cause the boiler to be incrementally more over-sized and cause even more short cycling.

Gsmith

Suggest you look at other reaasons for high fuel use. First choice is someone turned up the pressuretrol and the system is running at too high. Pressure

DuckMan

Thanks for the replies. These are good suggestions on where to start.

What's ironic is that after reading Fred's reply my wife and I remembered that during our annual condo association meeting just last month that the head of the condo association said that he had shut off one of his three radiators because his bedroom was too hot. Sigh...

Thanks again for the help!

JUGHNE

There is a good chance that the last replacement boiler was too big for the connected radiators.
Also there may be more radiation in each unit than needed.
100 years ago there were enough radiators installed to heat the building with the bedroom windows open at night.

Your building could be on it's 3rd or 4th boiler replacement, often a larger one was installed by a naïve plumber.

Do your radiators have 1 or 2 pipes connected to each?
There could be other factors in addition to running at high pressure. Air venting in another major item that could cause problems.

gfrbrookline

It is possible that when the boiler was replaced they had to include the edr of the removed radiators since heat is likely included in your HOA fees and you or a future owner could reinstall the radiators at any point. Hence the boiler is over sized and will short cycle. If you reinstall your radiators, or at least some or them you will offset your electric bill for the split units, help your building reduce the boiler short cycling and reduce unnecessary wear on the burner.

Fred

@gfrbrookline , those rads were removed three years ago. They should not have replaced the boiler with one that is over-sized. Since they did, it makes more sense to have the boiler down-fired or a two stage gas valve installed and everybody should be happy. Taking 3 of 18 radiators out is about 16%. Should be easily doable with down-firing or a two stage gas valve. I bet most of the other five units have at least one radiator shut off too. Everybody is contributing to the short cycling.

steamedchicago

The association is probably well within its rights to require you to reinstall the radiators, whether or not they're contributing to short cycling. You're lucky they were kept; otherwise, you'd be on the hook for finding suitable replacements.

Fred

@steamedchicago , I think not. The Association approved the removal of those radiators 3 years ago.