Dump Zone

[Bullet]

My home has cast iron baseboard heaters with a mono tee system for the water flow . The house was built in the 60's with only 2 zone valves which are in the return side . One for the basement and the other for the upper floor . I have a dump zone hooked up but for some reason it doesn't work . The temperature in the wood boiler didn't drop when I cut power to test it . The dump zone valve is opening and closing as it should . My question is shouldn't the water flow back to my wood boiler and back up through the supply to the rads ? My dump zone valve is piped in parallel with my zone valve to let the water flow past the zone valve and back down to the wood boiler . Would the fact that it uses a mono tee setup or the zone valves being on the return side have anything to do with why my dump zone doesn't work ? I have just installed a New yorker MF100 next to my oil boiler . I bought it used and am trying to get it working for this winter .

 

[Nofossil]

My home has cast iron baseboard heaters with a mono tee system for the water flow . The house was built in the 60's with only 2 zone valves which are in the return side . One for the basement and the other for the upper floor . I have a dump zone hooked up but for some reason it doesn't work . The temperature in the wood boiler didn't drop when I cut power to test it . The dump zone valve is opening and closing as it should . My question is shouldn't the water flow back to my wood boiler and back up through the supply to the rads ? My dump zone valve is piped in parallel with my zone valve to let the water flow past the zone valve and back down to the wood boiler . Would the fact that it uses a mono tee setup or the zone valves being on the return side have anything to do with why my dump zone doesn't work ? I have just installed a New yorker MF100 next to my oil boiler . I bought it used and am trying to get it working for this winter .

I think the monoflow tees are the culprit. They require flow to work.

 

[waynecub]

Hi Bullet
Make sure your circulator is not a IFC circulator. A check valve in the circulator will not work the way you have it hooked-up.
My old heating system I used mono T's with old cast iron baseboard and I had a auto dump zone that worked great. It wont work good if its on the same floor as the boiler, if it works at all. But if the zone is on the second floor then it should work. Check the circulator
Marcus

 

[Bullet]

Hi Bullet
Make sure your circulator is not a IFC circulator. A check valve in the circulator will not work the way you have it hooked-up.
My old heating system I used mono T's with old cast iron baseboard and I had a auto dump zone that worked great. It wont work good if its on the same floor as the boiler, if it works at all. But if the zone is on the second floor then it should work. Check the circulator
Marcus

The circulator on the wood boiler is a Bell & Gossett NRF-22 and the one on my oil boiler is a Bell & Gossett SLC-25 with 4 speed RPM . I don't think either of those have a check valve . We didn't have a plumbing or wiring diagram for the New Yorker MF100 when hooking it up so maybe that might be some of the problem . Thanks .

 

[Tarmsolo60]

I'm with Nofossil, you need flow for the monoflow tee's to work properly.

 

[Bullet]

I'm with Nofossil, you need flow for the monoflow tee's to work properly.

Thanks . I am not a plumber and have little understanding of how a dump zone is supposed to work . Am I wrong in thinking that for every amount of water that returns to the boiler an equal amount is pushed back up the supply side . Is it the water temperature that causes it to flow ? If someone can give me some description of how it works it might help .

 

[Tarmsolo60]

I'm with Nofossil, you need flow for the monoflow tee's to work properly.

Thanks . I am not a plumber and have little understanding of how a dump zone is supposed to work . Am I wrong in thinking that for every amount of water that returns to the boiler an equal amount is pushed back up the supply side . Is it the water temperature that causes it to flow ? If someone can give me some description of how it works it might help .

For a non powered dump zone to work the dump valve will open on loss of power, If the dump zone run leaving the boiler goes up in elevation the heat in the boiler will thermosiphon, letting the heat leave the boiler and pulling in cooler water into the return of the boiler and the cycle will continue getting rid of the excess heat.

However, monoflow tees operate by having water rush through the return monoflow tee creating a venturi effect and pulling the water through the baseboard. without a decent flow through the monoflow tee I doubt the heat will move through the baseboard.

the main loop might get hot by thermosiphon, but i doubt the baseboards will.

EDIT:
I just reread the replys and see marcuswayne says he had a similar setup working. If your circ has no check valve in it look for a flow control valve that might be stopping the flow.

http://www.bellgossett.com/productP...Flow-Control-Valves.asp?Part=BG_107037&Page;=

http://www.bellgossett.com/productPages/Parts-Flo-Control-Valves.asp?Part=BG_107018&Page;=

 

[Bullet]

I'm with Nofossil, you need flow for the monoflow tee's to work properly.

Thanks . I am not a plumber and have little understanding of how a dump zone is supposed to work . Am I wrong in thinking that for every amount of water that returns to the boiler an equal amount is pushed back up the supply side . Is it the water temperature that causes it to flow ? If someone can give me some description of how it works it might help .

For a non powered dump zone to work the dump valve will open on loss of power, If the dump zone run leaving the boiler goes up in elevation the heat in the boiler will thermosiphon, letting the heat leave the boiler and pulling in cooler water into the return of the boiler and the cycle will continue getting rid of the excess heat.

However, monoflow tees operate by having water rush through the return monoflow tee creating a venturi effect and pulling the water through the baseboard. without a decent flow through the monoflow tee I doubt the heat will move through the baseboard.

the main loop might get hot by thermosiphon, but i doubt the baseboards will.

EDIT:
I just reread the replies and see marcus wayne says he had a similar setup working. If your circ has no check valve in it look for a flow control valve that might be stopping the flow.

http://www.bellgossett.com/productP...Flow-Control-Valves.asp?Part=BG_107037&Page;=

http://www.bellgossett.com/productPages/Parts-Flo-Control-Valves.asp?Part=BG_107018&Page;=

Thanks again . I have gone over the piping layout and there is a flo-control valve in the supply side . It was put there in the 60's when the system was installed . There is a similar one in the website you posted . I don't know if removing it would be an option or if it might cause me other problems . There must be a reason for it being there in the first place . Do you have any idea what I might be able to do in this case ? Another thing that I noticed is the dump zone valve has what looks to be around 1/2 inch input and output piping where as the main zone valves are 1 inch piping . Would it being reduced from 1 inch to 1/2 inch have any effect on the dump zone operation ?

 

[Bullet]

Could someone tell me what the purpose of the flo-control valve is and what could happen if I removed it ? My zone valves are on the return side and the flo-control valve is on the supply side . If they were all on the supply side I could plumb in my normaly open dump valve to bypass both . Would it be ok to move the flo-control valve to the return side ?