In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I hate to ask for help, but I have gotten myself lost.
I recently bought (land contract) 2, 9-family buildings near cincinnati, ohio and have been trying to figure out which way to go to try and save money and to be ready for the future. Right now the heating bills for the building are $1k in Dec & Jan. The past peaks have been near $2k in the same months. I'm trying to get on the correct path for when this boiler craps out.
Boiler: Bryant cast iron from early 70s. 425k output (nice to see a temp gage showing 350f+ going up the 10" flue)
Sits in center of building. 2" copper off the unit T's to 1 1/2" copper that runs to ends of building and drops to 1 1/4 across floor, it then drops to 1" going up the the units. t's off the 1" to 3/4 baseboard in the units and returns to boiler same size as supply. Each 2 units makes a loop into the main 1 1/2 runs. Total of 4 loops.
This building is all brick, no insulation and has new windows with about 600sf per unit. Each unit has 2 doors and 5 windows. A rough calc heat loss on end units put it close to 40k. (less on center units) On a typical day I figure the units are getting just over 20k in heat. This would be why my end units are about 6f+ colder than the center units.
I don't have any room left to add more baseboard in the rooms.
I also need another water Heater soon. So now I'm trying to think ahead for what I should plan.
I thought about installing zone valves on the center units to lower the temps (75+ on cold days). It wont help with heat to the end units unless I turn up the boiler which in turn wont save any money. This boiler does use an outdoor reset.
Thinking of a new boiler with an indirect. If I add zone valves I need to cut and connect the baseboard since they supply from 1" copper with 1/2 unit fed to right and other 1/2 left.(3/4 fin) If what I understand I wont be using a condensing boiler? I normally have been pushing 140f water.
If I'm going to be doing remodel/replacement, Do I think about using a manifold to feed each apartment ?
Zone valves or the smaller pumps (pricing about the same?) each unit has about 60-65' of 3/4" fin tube.
The more I read, the more I'm losing myself.