New baseboard ragiators not working

[tripod]

I bumped out my kitchen and replaced old baseboard radiators with new ones (increasing the loop distance) and now there seems to be no flow through the new loops and no heat. I'm re-using the old check valves, maybe they are causing the problem? What makes the water flow through a loop when it could continue straight through the main 1" dia. pipe? the check valve?

[KField]

What creates flow in the system you describe is a venturi tee. It has a venturi in it that creates a pressure imbalance and causes water to go through it. You may have added enough friction to balance the imbalance. Your only solution if, in fact, that is what is happening, would be to add a ball valve on the 1" pipe to create even more pressure imbalance. It is not the preferred method but it beats re-doing everything. What size pipe is your new longer loop?

Ken

[tripod]

thanks for responding Ken, there are two new loops, one is 3/4"(baseboard radiators) and one is 1/2" (kickspace heaters). In the past few days the radiators have begun to heat up while the kickspace heaters are still cold. Neither loop has a bleeder valve, I think this is probably the root cause of my problem, do you agree? Should I add one to both loops?

[KField]

I think you should add an air vent to both and each should have one venturi tee too. That should make it work correctly.

Ken