cold radiator

vince_3

thanks so much for the ideas. i did install key vents on both the supply and return high points upon building the branch. I also installed a vent on the supply inlet on the radiator. I thought I had all of the bases covered. you could onlly imagine my frustration upon fireup. i am sure there is an easy solution somewhere in the works. I am in the St.Louis metro area and trying to find a residential hvac contractor with hot h2o knowledge has been next to impossible. THe norm here is forced air. I purchased Dans book several years ago after realizing that i may be betteroff tackling my my own heating problems myself. I have enjoyed working through the challenges posed by a system of this nature. Woould a b+g air vent be better than a manually operated key vent on the supply and return branches?

vince_3

cold radiator

maybe someone can help me, i have retrofitted a 60's era shaw perkins radiator into my homes split diverter tee heating system. my home is a one story frame 20's era that is heated with radiators on the living floor. the main runs in the basement, it flows oout of the boiler splits at the front of the house and follows the perimeter of the home. all of the radiators are upfeed withe B+G monoflow iron tee's, there is a tee on both the feed and return side of all of the radiators. the retrofit is in a newly finished room in the basement , i have read dan's book "how come", i have fed the basement unit off of the main as nearly as close to the configuration as shown in the book, upon refilling and bleeding and fire up the basement unit failed to heat up. due to some limited space and framing obstructions the supply and return tees on the basement unit
are barely wider than the radiator. this presents a problem because of the drywall has already been applied. also the unit has the feed and return taps on the same side of the radiator , one high , one low, i have the supply in the high side and the return in the low side, this makes this branch somewhat long and the nessesary turns in the piping to complete this may have increased the resistance to the point that nothing will flow throough the unit.although the unit is a down feed the supply and return piping comes off of the top of the main and travels in the joist space to maximize headroom. CAN I PUT A MANUALLY OPERATED VALVE IN THE MAIN AND CLOSE IT TO THE POINT THAT ALLOWS FLOW TO BE ESTABLISHED IN THE UNIT WITHOUT CREATING OTHER PROBLEMS DOWNSTREAM? ANY ADVICE WILL BE GREATLY APPRECIATED, THANKS , VINCE

[Deleted User]

may work.

but i think the valve would need to be between the two tees to the downfeed radiator..are you tees installed opposing each other? this may be a question to pose to ''ask red'' at B&G's web site.

Mike T., Swampeast MO

So the piping looks...

...something like this?

Are you ABSOLUTELY certain that you have ALL of the air out of the lines? It is entirely possible that you can bleed and bleed and never get air but still have air trapped in one of those lines.

Hopefully this is the first or last rad on that loop as a placement in the middle may well upset the temperature to those after.

I'm not a diverter-tee expert but I see no reason why you cannot install a valve between the tees to try to get flow through that radiator. A straight globe valve is probably the best choice as neither ball nor gate valves are really meant for throttling flow.

Were it me, I would install the valve and put a radiator key vent just on either side of the valve. Fill the system with that valve closed, vent the air on either side, run just the circulator for a while, re-vent and then open the valve and adjust flow as necessary. (But then maybe I'm weird about air and Murphy.) Globe valves themselves introduce quite a bit of restriction so just the valve might do the trick. Then again an air bubble may be the whole problem to begin with, but I do believe the valve/vent arrangement I mentioned would eliminate this as a problem.

joe_14

circ



you could add a circ to the supply line feeding that radiator just where the 1/2 inch supply leaves the tee wire so the circ to comes on the same the main circ comes on. this will overcome the high pres. drop.


joe. g.

dave_21

cold radiator/vince

regarding your connection to the main, you should have taken your connections off the bottom of the main not the top for a basement fed rad.The way you have done it causes air to lock up in the high point and it has nowhere to go.I understand you did this for the headroom , the only way to alleviate this now is to try and install air vents on the supply and return high points or to do the job over with the monoflow tees facing down.

joe_22

RE: cold radiator

Read heating q & a's, diverter tee section and Dan will explain how to use two mono-flow tees. You always use two mono-flow tees when you are below the heating main.