Supply and return wrong?

Nad12

Hello,

My daughter's house (2 years)has baseboard heat. I am not familiar with boilers and baseboard heat. I had to replace a broken pipe and purge the air out. There are three zones. 2 zones were no problem, but the last one has trapped air that I have not been able to remove.I studied the pipes and discovered that at least 4 of the baseboards are tapped off the supply on both sides (doesn't make sense to me, but I'm no expert) I'm guessing that this is wrong and the reason for trapped air.  Judging by the piping and soldering, this was a homeowners handiwork, as were many things in the house. If this is incorrect, could I cut the pipes on 1 side and route it into the return?



thanks

icesailor

Wrong?

Please send pictures. We love pictures here.

MrDucks

Mono Flo ?

Pics would be nice, Going to guess mono system

Nad12

Supply and return wrong?

I won't be at my daughters for a few days to take pictures. I have sketched a diagram of how the main supply is feeding the baseboards. There are 3 zones and I know there are 3 supplies and 3 returns, but for these 4 baseboards they feed from the supply pipe on both ends.  If this was a monoflo system, wouldn't the supply feed in one end then return back back to the supply? I won't be back there for a few days. I plan to take down some more ceiling tiles in the basement to see waht I can discover. I willtake some pictures then.



Thanks

Ironman

That's a Mono Flo System that You've Drawn

The only difference is the flow returns on the left side of the rads. The Tee on the return side will have an orifice on the through inlet side that causes some of the flow to divert through the rad.



It can be very difficult to purge air on these rads.

Nad12

Supply and return wrong?

Thanks for the info. I have been doing research on monoflo systems.  I am going to check the installation of the monoflo diverters. I am thinking I'll put in a couple of ball valves and bib in the area that is trapping air.  I'll let you know how I make out.

Gordan

Vents

What you need are air vents at each of the baseboards. Without those, you'll never get the air out. There may be vents on them already, without you having realized it.

Nad12

Supply and return wrong?

Gordan, Thanks, I'll check that out.

icesailor

Supply and return:

You can't "purge" a monoflow system. You can only vent the air out of them. There will be air vents on the heat emitters.

There is always some type of marking on a "mono-flow" fitting. As long as the marking faces the other tee on the main for the emitter, it doesn't really matter which way the flow is. It will work anyway. The emitters will never work if there is air in them. You MUST vent the air out of the emitters. The main is already vented. The air went into the emitters.