CGA-25 - 27,000 BTU Output Boiler, Spark Ignition - Series 3 (Nat Gas)

My 1948 3-family originally had a single 1-pipe steam system with cast iron radiators. While I prefer steam heat with cast-iron rads in a single-family home, the need to sub-meter was important. Separate gas meters and these little boilers really did the trick. Each tenant has their own heating control. Each apartment is roughly 1,000 square feet, and these boilers, along with new Slant-Fin baseboard and runs of Wirsbo hePEX made the job a possibility. The boilers are quiet, dependable, and efficient. I've had no problems at with them, and they look great in the basement, everything standardized.

I thought this boiler would be undersized for my common areas of the apartment building. The building total sq. ft. is about 5,000 and I am located in Minnesota. However, after a energy audit for BTU use we found this boiler to be the perfect size. (I must note the dept of energy complete BTU size based on the unit being placed indoors did help) I had originally considered a high efficiency boiler. However, these boilers require special PVC piping for an inlet and exhaust. I am always concerned about simple mistakes a tenant could make. Thus for an input to be accessible to tenants are their kids was a no no. If the inlet becomes plugged, it will burn out or at least make no heat, which would be very very bad in Minnesota. Nonetheless, a properly sized boiler will save you mountains of money compared to over-sizing and upping efficiency. Take my word for it, or talk to any experience HVAC/Plumber. Size does Matter! By the way, you can under size by around 10-15% according to the HVAC/Plumbing company I hired.