Not exactly radiant, but I'm trying to set up a 9 zone system with a TT 175 boiler feeding 17 cast iron radiators (3 rad per zone).   This system is a central heating system for 5 apartments in north jersey.


I believe the boiler out piping is 1-1/2".  The lines are 3/4 pex.  I'm looking for advice on these questions:

Go with zone valves or pumps?

Is there a prebuilt maninfold set up that would work for me?

Is there any boiler area set up idea that would make the install simpler?  :()


And if anyone knows..is it best to feed old "American Radiator Company" rads from the top?


thanks much.

The first question that I have is what is the heating design load required from each zone and each radiator. This will then determine water temperature and flow rate. What is a TT boiler.

apt 1 - 2 zones load 7500 each
apt 2 - 2 zones load 9000 each
apt 3 - 2 zones load 14000 each
apt 4 - 2 zones load 16000 each

The rads I have are between 10 and 18 columns, 5 sections, 24" high cast iron.  A ten column has an puts out about 2750 btu an hour at 150 degrees.  two rads each zone.

The TT 175 is a triangle tube solo 175 boiler.

I'm running a 60 gallon heat transfer products indirect off the boiler.

On old cast iron boiler conversions, I start with a heat load analysis, followed by sizing the radiation. Zone valves are more efficient in most gravity boiler conversions but flow control has to be attended to and primary/secondary is rarely needed if you do the math and the condensing boiler manufacturer allows it.

http://www.badgerboilerservice.com/boilerchoice.html