We have similar construction and vintage of the house. This one is a 1900 square foot colonial with typical foyer, living room, dining room, sunroom, and kitchen on the 1st. Four bedrooms and bath on the second. Built in 1921 with 2x4 construction. Updated periodically with R-11 insulation in the walls and about R-19 in the attic floor above the second floor ceiling.

The house started with an old cast iron, American Standard Boiler, with a giant firebox and large, cavernous heat transfer fins. This boiler remains to this day, however, improved with a Beckett, flame retention head.

It also had 2" supply lines covered in asbestos, running through the basement to the 3/4" risers to the individual radiators (9 of them). Naturally, it was only one zone. You would typically wait two hours for any serious temperature increase, because the system held 125 gallons of water (I measured it).

Fuel consumption was typically 1400 gallons per year, with the temperature kept conservative.............68 degrees during the day and 62 degrees at night. No clock thermostat.

The consumption included the hot water requirements via a tankless coil within the furnace.

After about 5 years of this BS, I finally had enough. Naturally the asbestos and the 2" pipes had to go. So, I carefully planned a project that included removal of all the pipes in the basement, including the asbestos. It was to be done in two stages............one-half the house at a time. Since each radiator in the house was fed directly from the basement (parallel system), it made sense to put a zone valve in the feed to each radiator and control the valve with a thermostat in the room. Maybe a bit of an overkill, but, the difficulty of obtaining two zones (double pipes in the basement, and an additional circulator) was about as costly as adding nine zone valves.

So, after about three years (on and off), I finally got it all finished. The furnace feeds 9 zone valves via 1" copper pipe, fully insulated. The risers in the walls remain at 3/4". Four of the nine zones have clock thermostats. I keep my office at 70°F. during the day and all other rooms remain at 60°F. In the evening, the living room is heated to 70°F for the evening hours. All rooms, other than my bedroom are reduced to 55°F. at night. The bedroom is reduced to 61°F.

The other significant change was a reduction in boiler temperature from the typical 180 degrees to 155 degrees. The cast iron radiators have tremendous radiating capability and the cooler water has posed no issues. The only time that hotter water is preferred is when the ambient temps drop down to below 20°F. If that happens, I simply go down and raise the boiler temp up slightly. I can manage the hot water with 155 deg. boiler water because the unit has a 10 gallon coil. It provides all the hot water desired at a temp of approx 120 degrees. If I need to do a hot wash, or a diswasher load, I have installed a switch, at the top of the basement stairs, that will send the boiler up to high limit (185 deg.) I do the required wash and then drop it back to 155 deg.

The consumption varies between 650 and 800 gallons per heating season. Last year was brutal and it used 800 gallons. This year, knock on wood, is running warmer than usual, so I'm hoping for 700 gallons. It all depends on the Jan-Feb. temps. If we remain close to 30 degrees, I'm fine. But, if we get several weeks of 25 deg. days and 10 deg. nights, then I won't make it.

So, fuel oil is currently at $2.159 per gallon (as of two weeks ago). My cost for a 12 month period will be approx. $1500.

The house remains with the original cast iron, American Standard boiler.


Hopefully, the above can give you some tidbits for improvement. PM me for any additional details needed.