Gas fired boiler not heating one sector.

[jolleyi]

I had a leak in the sector that services the master master bedroom and sitting room of my house. (3rd and 2nd floor).
I replaced the failed joints at the end of the baseboard unit and turned the water back on. I can get 2 other zones to heat up but cannot get water into the zone i repaired.
I have bled the system at the highest point, (in the bedroom) and water is coming out there. however hot water seems not to want to flow past the zone regulator, making me think i may have an airlock somewhere else in the zone as it does operate on 2 floors.
i manually opened the zone regulator (honeywell) but still no water would flow into it.
Any ideas how to clear it?
thanks
Ian

 

[johnjh2o]

What type radiation do you have? It sounds like you have air in the system. Just bleeding the highest point in the system doesn't remove all the air.

John

 

[jolleyi]

I have baseboard registers in most rooms with a few areas of the same type of copper pipes with aluminum fins under some floor areas, particularly the kitchen. The furnace is gas fueled.
The zone giving the problem is split between the 2nd and 3rd floor (mbed and sitting room as mentioned) I have another 2 sectors one of which feeds the bedrooms (one on the 2nd floor and 2 on the 3rd floor) this sector is working fine, but there again I did not drain this sector to repair the leak.
The copper pipe in the region of the repair seems cool and also sounds as though there is water in it so i'm assuming I have an airlock somewhere else.
Thanks
Ian

 

[LiQuId]

you should be able to bleed from the baseboards, Sometimes you need to shut the system down to allow the air to move to the high points in the system. if the pump or zone valve is pumping against an air pocket it will continue to do so untill the air is bled out.

Isolate the systems and work on bleeding one zone at a time.

 

[jolleyi]

The problem zone does have a bleed valve and I let all the air out, (not a whole lot, but hard to say) now only water. However still no hot water is getting through. Other zones are fine, (heating up)
The problem zone does not let hot water get anywhere much past the honeywell valve, have operated it by both using the thermostat and by sliding the lever at the back which opens it up, but no significant flow of hot water, (some does get through the valve into the copper pipe beyond but stops at about 1 foot or so beyond the valve. I'm guessing this means I have an airlock somewhere in the zone where it cannot be bled by the bleed valve at the top.
Any ideas?

Many thanks for the replies so far
Ian

 

[johnjh2o]

You may have to purge the zone. Need a picture of the boiler and piping to instruct you how this should be done.

John

 

[jolleyi]

I took a look on the web at purging a zone and armed with that info I waited until the furnace was cool, made sure all the zone controllers were shut except the one to purge, (opened it manually, and as a precaution i switched off the gas supply to the furnace). I closed all the water returns from the zones to the furnace. Then by pressing the top of the Taco 3350 pressure reducing valve, I pushed water thru the furnace, thru the honeywell zone controller, up and around the system and then vented the return to atmospheric pressure. Evidently the Taco puts out more than 30psi when depressed as the pressure reducing valve on the furnace was firing off and is is set to 30psi. I did this until i could hear a constant flow of water, without bubbles, and after returning all valves etc to their original positions, I fired up the furnace and the zone was back in business again.
Appreciate your help in suggesting I purge the zone.
We will have heat this winter!
Ian

 

[johnjh2o]

Good job glad to here your back in business.

John

 

[havasu]

It is hard to even think about heat for me since it was 106 today. Thanks for the follow up!

 

[LiQuId]

thank YOU for posting that you eventually fixed the problem, you have no idea how often we dont hear the end results here.

glad the forum was able to help you.