hot water baseboard, lost one zone

srmaietta

Hey all, I'm in a new house, moved from Steam to hot water baseboard.. Went from a 100 year old system to a 40 year old system.

House is a split level, bottom floor has the boiler room and lower zone. Upstairs has the living room and bedroom zones. Heat has been fine up until a week or so ago.
Issues:
--Basement zone (at/below boiler level) will not get any heat into the baseboard.
--Bedroom zone is very uneven. one side of the house (two bedrooms) sit at 75 when the thermostat side (master bedroom) is at 67.

The boiler is a HydroTherm HC145, Zone valves are Erie "hotlines". The boiler room is very cramped. Circulator is an old taco 007.



Thermostats all drive the motors and open the zone valves as far as I can tell.
I took the back flow and regulator out and cleaned them up so they function again -no water was passing through either of them, they were completely blocked with rust and sediment. I flushed out the three zones with the regulator toggle up and out through the spigot on each zone, one at a time. System is sitting steady at 15 lbs pressure.
Even after flushing, still no heat in the basement zone. New regulator, and back flow preventer, expansion tank and air vent coming tomorrow.

--Could the circulator pump have gone, thus leaving the basement zone helpless? while gravity brings heat to the upstairs zones (unevenly) ?
--Could be the basement zone valve?
--Shouldn't there be some valves near the zone valves to facilitate getting a good purge of the system?
--Are the screwdriver valves below the spigot valves (on the zone returns) some sort of flow regulators?

thanks for any thoughts.

EdTheHeaterMan

The screwdriver valves are used to flush the water thru the system and out the flush valve opening. if you flushed the zones with that valve open (screwdriver slot parallel with pipe) then the flow was short circuited and did not push the air out of the loop.

after you replace the

New regulator, and back flow preventer, expansion tank and air vent coming tomorrow.

and it does the same thing, what will you check next?

EdTheHeaterMan

Here is an illustration that may help. If the zone valve is open and the purge valve screwdriver slot is parallel with the pipe, the water pressure flow will take the path of least resistance. See the purple water pressure line in the first illustration:This path of least resistance will not push water thru the baseboard loop to force the air out of the system.


In this second illustration the screwdriver slot valve is perpendicular to the pipe. This closes off the path to the purge valve, making the long loop around the path of least resistance, and will push the air out with the water flow. See the purple water pressure going the long way around.
You need to build up at least 20 to 25 PSI pressure for the best results. Look on YouTube for better instructions on how to build up more pressure without going over 30 PSI because that will open the relief valve and make a mess.

Big Ed_4

The third purge valve with the slot looks closed

EdTheHeaterMan

Big Ed_4 said:

The third purge valve with the slot looks closed

That could cause you to have no flow thru a zone!

EdTheHeaterMan

This picture is showing the purge/balance valve with the screw driver slot in the open position

This one is in the closed position.

srmaietta

Thank you Ed for the info on the purge-balance valve.  Will straighten that out tomorrow and purge the zones again.  Hopefully get a good purge and flow.

if still nothing through the basement loop, then I will check if the circulator pump is actually pumping, and check if the zone valve is actually opening/closing. (Tips on checking an Erie type zone valve in a setup as you see here would be appreciated)

thanks again.
steve

EdTheHeaterMan

The Erie Zone valve that I am familiar with was called a Pop Top® valve because the actuator head actually popped off the valve by pressing a black button on the side. This was for easy access to replace the actuator. Those valves were introduced over 20 years ago. If your Erie valves are older than 25 years you may not have the Pop Top® valve. However, the actuator on the older valve operates the same way. There is a small metal tab that protrudes from one end of the actuator housing that is used to manually open the valve. See yellow arrow: You can move that tab to manually open the valve. The spring will automatically close the valve when you release the tab. There is a notch in the slot where you can rest the tab to keep the valve open. See this illustration

srmaietta

Okay gents… replaced regulator and backflow valve that were completely inoperable and leaking.  Replaced 25 yr old expansion tank and moved it to the other side of boiler so accessing the back of the boiler is even possible.  New blow off valve, air vent, and zone purge hand valves.  

Filled system (no leaks! Stays at pressure!)
 Closed the zone screwdriver valves as was mentioned  and purged all 3 loops of nasty water and air..  kept the pressure at 20-25 psi to make sure I was getting all the air.

Dialed the zone screwdriver valves back to “on” (up and down).

system heats up and air valve is doing its thing and all seems well, stable at 15 psi.

BUT still no heat in the first floor (boiler level) loop! Even with the zone valve manually opened.  And still what seems like very slow heat flow through the upper two zones.

—circulator pump is bad?  Can hot water /cold water differential be enough to cause the water to circulate through the upstairs zones?  Can I check its operation by listening using a stethoscope?  

— Bad zone valve in basement.?  How to definitively check this?  Is this old old Erie worth rebuilding or should I just put a new one in?

thanks for further thoughts!!

EdTheHeaterMan

During the purging process, was the water flow (after the muck and air was gone) strong and steady like the garden hose could operate a lawn sprinkler?

If the water flow from purging is weak, there is a blockage somewhere. If the flow was strong, then you may have a defective or gummed up with smutch circulator pump. (Gummed up with Smutch are technical terms used in the field by us professionals)

hot_rod

Those Erie zone valves have a removable bottom plug. So with a mirror you could look inside see if the flapper moves.

If it does and you are purged, you are down to the circ not working properly. Could be the impeller plugged with smutch, a broken shaft, bad/ open motor

Usually you can hear water flow as you slowly, manually open a zone valve

Big Ed_4

Sounds like a bad pump. Are the upstair returns hot or warm ? Warm check the circulator .

Robert_25

It sounds like a dead circulator to me, but usually those 007's make noise to warn you. Considering how tough yours is to access, if you have to drain the boiler down and squeeze yourself in there to inspect the circulator, I would replace it.

mattmia2

Robert_25 said:

It sounds like a dead circulator to me, but usually those 007's make noise to warn you. Considering how tough yours is to access, if you have to drain the boiler down and squeeze yourself in there to inspect the circulator, I would replace it.

I would make a straight pipe with 2 flanges and a piece of pipe and put that in place of the circulator and move the circulator to the supply after the air scoop and expansion tank where it belongs.

HomerJSmith

If you are going to replace the circulator, I recommend a Grundfos ups15-58fc because they can be taken apart and cleaned and a Taco cartridge pump can not, beside which Grundfos pumps have 3 speeds. One would have to replace the cartridge in the Taco which is almost the price of a new pump.

srmaietta

when I purged it using the screwdriver shutoffs, I got lots of brown water and air for a minute or so..  then had a solid stream for another 2 or three minutes then shut it down and moved to the next one.  Confident it’s purged thoroughly.

I have felt temperature gradient flow through the dead zones valve so I'm leaning towards the circulator.. 

…And I’m going in.

—anyone know if the drain valve on this boiler (hydrotherm HC-145) is 1/2” or 3/4”?  I’m assuming it’s going to leak and want to have a new one here for that…

Would love to repipe this and add zone controller, multi speed pumps, the whole 9, but really just trying to get her going.  I’ve had a brand new Taco 007 here for a few days now.

thanks again!
~Steve 

EdTheHeaterMan

That valve actually has a Hydrotherm part number 51-1201.
That is a 3/4" male pipe thread by garden hose thread valve.

mattmia2

i'd use one of these and a nipple. with the cap it prevents accidents with the handle and in a pinch you can use the cap if the valve won't hold:
https://www.supplyhouse.com/Webstone-40313W-3-4-Female-x-Hose-Full-Port-Ball-Valve-Lead-Free

srmaietta

Thank you Ed!  I saw the part number but not a picture and thread size.

Mattmia, that looks like a nice setup.  .

hot_rod

Another option, a bit cheaper

srmaietta

Out with the old!!!

blown capacitor! ??   The motor seemed to spin fine, so hopefully that blown capacitor was keeping us from operating. Any thoughts if this could’ve hurt the relay or anything like that?

mattmia2

Nahh, new cap and it should be fine. I would still move it to the supply so you don't have to climb in behind the boiler again.

Big Ed_4

At this stage replace the whole pump for a shot gun repair.

srmaietta

She kicked on and is pumping like crazy and we’ve got heat !!!  All zones just as she used to do.
Just in time for this weeks upcoming cold spell..

Plus I’ve got a backflow preventer and regulator that work, a new blowoff valve and a new expansion tank that is now routed out of the way for future repairs.  Win win win…. 

Had to grab new bolts and I filed and cleaned the flange mating surfaces.. all sealed well.

Found “just tight enough” to keep the boiler drain valve from dripping.  That thing did not want to come out and I didn’t want to break anything.

Thanks guys!! 
Steve

mattmia2

You can always throw a hose cap on a drain that won't hold in a pinch.