The house is currently set up with 6 zones. It has a huge Buderus boiler with 3 pumps - one for the radiant heat in kitchen, one for 2 zones on the far side of the house, and one for 3 bedroom zones. All piping is 3/4 copper. The boiler is set at about 180 degrees, but i'm not sure of the pump speeds. The boiler and pumps are in the finished basement
The question is about the master BR and small bath (5X8) on the first floor, nearly directly above the boiler room. Together these 2 rooms are their own zone (one of the 3 br zones), and the only rooms with old fashioned radiators - one in the BR and one in the bath. The thermostat for this loop is in the bedroom. They are currently set up with a single loop with monofow tees off the 3/4" main loop down to 1/2" to each radiator inlet and outlet (4 total). I assume the monoflow tees were in place not only to make sure enough flow got to the individual radiators, but also to prevent a block in the flow should either radiator be closed off by the occupant using the handle on the radiator itself.
I want to replace the radiators with baseboard in the bedroom and a kickspace in the bathroom. I'll also be replacing the copper currently under the room (but not in the boileroom) with 3/4" Oxygen Barrier PEX. Now the question:
Since there are only 2 units, can I run with a single loop, bedroom baseboard first (3/4" slantfin), bathroom kickspace second, and forgo the monoflow tees completely? Most of the kickspace installation guides recommend at least one monoflow Tee, but I think that's for situations where there are more (particularly downstream) heat exchangers in the loop.
My gut is that with only 2 heat exchanger units on the loop, and the smaller diameter unit on the return side, it should work OK. I should even be able to control the heating in the bathroom to modulate the two rooms in the same zone by setting the kickspace fan on either high or low. My biggest real concern is that the 1/2" piping in the kickspace will restrict the flow too much and possbly strain the pump unit back at the boileroom. Am I leaning in the right direction on this?
Last edited by tacampbell; 10-12-2008 at 10:40 PM.