Is zoning possible on old hydronic boiler system?

jac34

I'm looking to replace my oil fired boiler serving cast iron radiators to a propane boiler in the spring; there are 24 total rads in the house. Currently, one thermostat runs all 3 floors and I would love to put 2nd and 3rd floor on one zone and have the 1st floor on its own zone.

Not knowing much about boilers, I'm following the pipes and it looks like 2" cast iron pipes coming off then branching into the risers which look like 3/4". Each rad has its own supply and return that seem to be accessible in the basement.

My kitchen/breakfast room were remodeled by previous owner in 2009 and put on its own thermostat. They installed an air handler in the crawl space that the boiler serves and then blows hot air over the heated coil through vents. When they did this, it looks like they capped some of the old radiator spots and ran new 3/4" copper pipe from boiler to air handler.

So, it seems it can be done but how costly would it be to zone out those rads? Seems labor intensive but what do I know?? Figure now is the time to do it when new boiler goes in. Unless it's a ton of dough, then I will just live with it.

Steamhead

Instead of changing all the piping around, consider using thermostatic radiator valves on the upper floors. These act as limiters so you can keep these rooms cooler if you wish.

I wouldn't install these in the bathrooms though. No one likes a cold seat.

newagedawn

is it one pipe or two pipe, steam, hydronic, sounds hydronic

j a_2

Post some pictures

STEVEusaPA

@Steamhead has the answer. Most likely you can zone separately without major repiping/remodeling.

Paul48

Either way.....Have someone standing by, with smelling salts.

jac34

2 pipe hydronic. See some pics

STEVEusaPA

Looks like it's already has some zoning. Also, how close are the oil tanks to the boiler?

jac34

They are right next to the boiler.

The only zoning is to the indirect DHW tank and then over to the air handler that serves the kitchen/breakfast room on its own stat.