Banging in large closed loop system (and other questions)

Denton Taylor

Greetings experts:

I live in a 4-story 35 unit NYC co-op converted from a factory building. The boiler system is 5 gas-fired Slant-Fin units. 3 supply heat thru circlating pumps and the other two supply hot water thru smaller pumps. I believe the hot water is made up as needed by a mixing valve but anyway the heat is what is giving us problems.

We are trying to understand more about this system and as I seem to be the most mechanically inclined person in the building (not by much!) I get the job.

The conversion from factory to apts was slip-shod in many areas. We do not have schematics of piping and risers.

Every apartment on the top floor has a panel next to the baseboard unit allowing access to some form of bleeder unit. We always bled them manually just before heating season to eliminate knocking in the system. A few years ago our heating contractor suggested we install automatic beleeders, which we did. They are small brass units maybe 1.5" dia x 3" high with 1.4" threaded nipple at the bottom of each that screws into the top of the pipe.

This year a couple of apartments are experiencing serious knocking. Our heating contractor (a new one) told us that most likely the auto bleeders are clogged. I had the occasion to remove one and it was full of gunk.

Do you guys think replacing all the bleeders would solve the knocking? We would like to do it ourselves if it would. The bleeders don't seem to be labeled so I wonder if anyone could ID them from my description above?

Also I assume all we would have to do is shut down the boilers, the circ pump, depressurize the system, install the bleeders, and reverse?

Finally, I have a question that has never been answered, or rather, has been answered in conflicting ways by different contractors.

Is it essential for every apartment to open the baseboard/Danfloss valves to the maximum, or to some point of open state, in order for water to flow to every apt?

I'm pretty sure thru experience that all the apts on the first floor, which have large cast-iron baseboard units, and are also large loft-style apartments, must be full on. But we're not sure about he rest of the building, and of course we don't have diagrams to help us.

Thanks in advance!
Denton Taylor

Unknown

Wow

Lot's to talk about. Would you give me a call at Slant/Fin tomorrow, and I can spend some time with you to answer your questions?

I'm in Technical Service, and our direct number is 800 873 4346. My extension is 456.

Noel Murdough

Slant/Fin

bb

please call us for more assistance

Hello Denton:

I would be more than glad to disucss this with you. Please call me @ 443-512-0266

Warm Regards,

Bill Burton