Hydronic Floor Heat Problem

[Mark Jenkins]

We bought a house with an early 50's hydronic floor heat system.

Built in 1951
Flexicore floor on first level (3,300sqft)
Four wall/floor radiators on second level (1,000 sqft)
9 zones
Barber Coleman controls:
Big Locking wall cabinet with four 30amp fuse/switch combo's on the right
side
2 huge transformers
Control Unit with 3 vacuum tube sockets)
only the first two tubes are installed the third one is just lying there
disconnected
Tube Tube Empty

7 Barber Coleman zone valves <-Really big industrial looking monsters. look
original
Burnham IN7 natural gas boiler (new)
3 B/G circulating pumps (new)
2 new B/G pump motors (new)
1 18 Gal Expansion Tank on the return circuit
1 18 Gal Expansion on the feed circuit
All cast iron main piping
All Copper distribution lines. <- Is this cause for any concern?
I have no idea if copper pipe is used in the floor themselves (Was Wirsbo
available here in the early 50's?)

The return "bleeder" valves located in the boiler room (6 of 7 of them) are
all dripping very slowly. The 7th is stuck closed and is not dripping and
that zone works great. I assume I should replace these.

1st Pump is for the second level and that zone in only controlled by the
pump (no zone valve)
second level has only 1 thermostat.

2nd Pump Handles the first level
1st level has 7 thermostats and zone valves

3rd Pump Handles the basement floor
basement has only 1 thermostat
approx 1,500 sqft
No Zone valve
basement floor appears to get only return water from the system but heated
up real nice.

The whole system looks like it belongs in some kind of industrial/school
building.

I have a problem with 4 zones on the first level. The pipes after the zone
valves are not getting hot.

I found a stuck butterfly valve up to the second level (No zone valve, just
a circulating pump). A couple of whacks on it with a hammer freed it up and
we have heat upstairs! Yeah!

Well, this got me thinking that maybe the zone valves had stuck closed (is
this possible?) so I started banging on more valves and I did manage to get
another zone fixed. I don't know if the banging did it or if I just bled
this zone better then all the others.

On the next zone as I was banging on the valve I slipped and hit the copper
pipe and separated the elbow from the pipe and made a huge flood in the
boiler room! ;-(

I shut down the thermostats and it closed, water continued to spew forth
and I managed to re-connect the pipe and the flood waters parted.

The broken pipe has been fixed properly.

I had to drain the system to perform the repair.

I have bled the lines, have clear running water with no air bubbles and
still no heat in those 4 zones.

Do I need to bleed these four zones more than I already have? I thought I
did a pretty good job on them.

The boiler manual states that I should bring the new water up to approx 180
degrees for a couple hours to remove any corrosive gases that may be in the
water then bleed the system again. Is this really necessary? I know I will
need to drain the system again to replace the bleeder valves so I want to
make sure the filling of the system is done correctly this time around.

If I increase the pressure to approx 24psi all zones get hot. The boiler
will not maintain this pressure as it's release valve regulates it back
down to approx 18psi then all 4 of the suspect zones go cold again.

Even with all zones shut down and only one of the four opened, it stays
cold unless the pressure is increased back to approx 24psi.

Any ideas?

Thanks

Mark Jenkins
ma...@pcsincnet.com

[Wild]

>2nd Pump Handles the first level 1st level has 7 thermostats and zone valves.

>I have a problem with 4 zones on the first level. The pipes after the zone valves are not getting hot.

Your system does it have one big loop with zones off of it or just
headers with zones off of it.. ( I am assuming that it is a header type
with zones off of it.)

>The return "bleeder" valves located in the boiler room (6 of 7 of them) are all dripping very slowly. The 7th is stuck closed and is not dripping and that zone works great. I assume I should replace these.

Is there a valve after the bleeder ?? If not i can not be bleed
correctly.. ( I am assuming that your boiler is in the basement!..)
This would put your bleeder below the area to be bleed.. Bleed with
unit at its hottest and off (no circ pumps running, sit 10 or so mins)
this will let air settle so it isnt moving on you, the heat also
separates the air from the water.. This is what the comp was referring
to. Everytime water is introduced air is mixed in with the cold (cool)
water.. Then separate when heated..

>If I increase the pressure to approx 24psi all zones get hot. The boiler will not maintain this pressure as it's release valve regulates it back down to approx 18psi then all 4 of the suspect zones go cold again. Even with all zones shut down and only one of the four opened, it stays cold unless the pressure is increased back to approx 24psi.

Ok when you say release valve, is this a valve on the boiler the blows
off on you?? this valve should be rated at 30psi. There also should
(maybe if not manual fill.) be a fill valve on system, you can adjust it
to 24 psi, but i would replace the relief valve (<-your release valve)
first..