Comfort Line - Questions and Answers

In this quarter's Questions & Answers segment, we are trying something a little different. In 1984, the United States Environment Protection Agency issued a publication titled, "Get the Most from Your Heating Oil Dollar." In it, the EPA concluded that properly serviced equipment cuts operating costs and pollution. While the publication is old, it contains much useful information that is still largely relevant today. Below (with minor spelling and grammatical corrections) is a reproduction of the 1984 EPA brochure. If you would like a copy of the original, give us a call and we will be glad to send you one.

In several studies of residential heating equipment (warm air furnaces and boilers) sponsored by government and industry, it has been found that homeowners can save money and reduce pollution by having their oil burners serviced annually. The following questions and answers provide useful information to homeowners who heat with oil:

How much money can I save by having my oil burning equipment serviced annually?

The amount a homeowner could save will vary depending on the geographical location, present condition of the heating equipment, the price of fuel and other factors. For example, a homeowner burning 1,300 gallons of oil per year in a very inefficient heating system could save $190 in fuel costs at a price of $l.15 per gallon with proper servicing. This is a 13% savings in the total fuel bill as the efficiency of the oil burner is increased from 65% to 75%.

How much pollution reduction will result from proper maintenance of oil burning equipment?

In a recent study, it was found that by identifying and replacing non-tuneable units, carbon monoxide (CO) was reduced by more than 65%, gaseous hydrocarbons (HC) were reduced by 87% and filterable particulate was reduced by 17%. By tuning the remaining burners, in addition to replacing non-tuneable units, the total reductions were as follows: smoke was reduced by 59%, CO was reduced by more than 81%, HC was reduced by 90% and filterable particulate was reduced by 24%.

Why should I have my oil burning equipment serviced annually?

Many people don't call for service until the heating equipment fails. Unless this occurs during normal working hours, the homeowner will usually have to pay for the service at higher hourly rates. By having annual maintenance during the summer months, unexpected equipment failures are less likely to occur. Also, burner performance can deteriorate over a period of time. Nozzles and oil filters should be replaced annually to assure proper burning performance.

Can I service the equipment myself?

It is recommended that a qualified oil burner service technician perform the work. When nozzles are changed, the excess air level normally needs to be adjusted. To do this properly, special instruments are used to measure the following:
· Carbon dioxide (CO2)
· Flue gas temperature in the stack
· Smoke Number
· Stack Draft

Most homeowners do not have access to the equipment needed to make these measurements and do not know how to use the equipment properly. Also, the service technician has a better understanding of how to diagnose problems that may be encountered, and should be familiar with any safety codes or standards that apply to the heating equipment. The furnace owner should inspect air filters monthly during the heating season and change them as necessary. Air filters should be replaced at least twice during the heating season and more often in some cases. Dirty filters reduce furnace efficiency.

Should I have my furnace vacuumed periodically?

Yes. Soot serves as an insulator and significantly reduces the amount of heat transferred to the house. Therefore, when needed, vacuuming can save the homeowner in fuel costs. Depending on the smoke level, a furnace may need vacuuming yearly or as infrequently as once every five years. Ask the service technician for a furnace inspection to determine whether vacuuming is needed. If the burner is properly maintained by keeping the smoke number below No. 2, the furnace should not require vacuuming very often.

What should the values of CO2, net stack temperature, smoke number and stack draft be?

A new oil burner with a properly matched furnace or boiler should operate with a minimum of 10% CO2 at a maximum smoke No. of 1. The following table provides a general range for a typical (gun-type) oil burner.

CO2%	11	Excellent
	9	Average
	6	Poor
Smoke Spot Number	0	Excellent
	1	Excellent
	2	Good
	3	Average for Untuned Burner
	4	Poor
	5 or higher	Unacceptable
Net Stack* Temperature(F)	400 to 600	Average for Original Equipment*
	600 to 700	Average for Replacement Burner**
Stack Draft (a measure of inches of water on gauge)	0.04 to 0.06	Average for non-forced draft units. For draft units and other types, follow the recommendations of manufacturer.
*Net Stack Temperature is actual stack temperature minus furnace room temperature. **Higher temperature require adjustment

How much combustion efficiency should I expect?

An efficiency of 80% or above is excellent. This means 80% of the heat received from the oil goes into the house, while only 20% is lost to the atmosphere. 75% to 79% is good, 70% to 74% is fair and below 70% is poor. If the efficiency is below 70%, the burner should be readjusted. If an efficiency of 70% or better cannot be achieved, or if adjustment increases the smoke number significantly, the burner should be replaced. The savings in fuel cost will offset the cost of the burner over a period of time.

If my service technician does not measure C02, smoke number, stack number, stack temperature and draft, what should I do?

Request the company to send another technician who can and will make the measurements. If the company cannot provide proper service, it is recommended that you find a company that can. These measurements are essential for proper burner servicing.