Anchorage, Alaska 2011

 

Synopsis

The below Homart Sears and Roebuck oil fired cast iron boiler (before demolition in 2011) was installed in a 1,430 square foot Ranch Style home the year the building was built, 1958; making the boiler over 50 years old. The Boiler rating is about 140,000 btu which is oversized for this application (A Heat Loss Calculation was performed during this survey). Cast Iron boilers have a normal life of 20-30 years if preventative maintenance procedures have been followed through its lifetime. The boiler has exceeded its lifespan.

SURVEY: OBSERVATION & COMMENT

(1) Efficiency: The cast iron boiler was originally oil fired and than converted to gas fired. Oil fired boilers not cleaned properly of soot and slag deposits around the flues and mineral deposits in the waterways have a tremendous amount of efficiency loss. Due to the age of the boiler 50+ years it can be only assumed that efficiency of the boiler is in the 60 percent range or less.

(2) Boiler operating 24/7: The boiler operating on old antiquated controls maintains a boiler temperature of 140F 24/7 year round even when the thermostat is not calling for heat. This wastes natural gas especially during warm periods when the boiler is not needed.

(3) Gas Utilization Equipment in Garages per Uniform Plumbing Code adopted by the Municipality of Anchorage: "Gas utilization equipment in residential garages and in adjacent spaces that open to the garage and are not part of the living space of a dwelling unit shall be installed so that all burners and burner-ignition devices are located not less than 18 inches above the floor."

A. It was observed the hot water heater meets code requirements

B. It was observed that the Boiler did not meet code requirements.

(4) Garage Appliance Protection: It was observed that the hot water and boiler are not in compliant with the Municipality of Anchorage code requirements.

RECOMMENDATION

(1) Replace boiler due to it has exceeded its life expectancy, and is oversized with a new 80 percent plus efficiency boiler that is sized correctly for this application. The boiler shall shut down completely on no call for heat from the thermostat.

 

 

In discussions with the owner many months after the new boiler was installed 50% reduction in gas bills was achieved.