mono flow problem?

PTP

I am taking care of a garden style condo conversion approximately 300 units old style radiators. project built in 1946.........all piping is original. I am now having problems with a few of the basement condos that have Mono flow tees down to them as the mains are over head of these units. have a great flow rate.... I am 60 years old and have been around a while but this has stumped me. Has anyone heard of the Mono Flow tees going bad?

Mike Kusiak_2

Dowmflow problems

I am involved with a similar monoflow system in a 1950's garden apt complex, and have experienced similar problems with some of the downflow fed convectors. In some cases , the problems have been caused by dirt and rust collecting at the balancing and shutoff valves of the convectors. The valves are of the rotating vane type, and have a tendency to clog and collect particles which fall down the piping from the monoflow main. Removing the convectors and cleaning or replacing the valves has corrected the problems in most cases.



I do have a few which still don't heat right after the valve cleaning, so there may be something going on with the monoflow tees themselves in these cases. It is possible that the flow restrictors in the tees have corroded away, but it is so difficult to disassemble the mains to check visually, that i have not gotten to that point yet.

icesailor

Monoflow pumping:

And I think that if at sometime in the past, someone replaced the circulator for the monoflow zone with a bihher corculator and tried to "push" the water harder, it may make the down fed radiators less efficient.

Or so I understand. Hot water doesn't like to go down.