Gas Appliances Jim Lambesis Recently I have come across some important safety information concerning the use of gas refrigerators. Since many alternate energy folks use gas refrigerators, the possible hazards associated with these units should be known. Below is a warning quoted directly from a poster distributed by Servel. "The U.S. Consumer Product Safety Commission (CPSC) says that old model Servel refrigerators have caused at least 14 deaths nationwide as the result of carbon monoxide poisoning. These refrigerators continue to be used in hunting cabins, vacation cottages and remote areas of the nation where there is no electricity, or where gas is a preferred energy source. To protect yourself and your family from potential hazard, stop using your old Servel gas refrigerator immediately. Over a period of time, especially if the refrigerator has not been used recently, the gas burner can be fouled by dust, dirt, rust, spider webs or other obstructions. This can cause improper combustion of the fuel, leading to the production of carbon monoxide, a colorless, odorless and deadly gas. Any gas refrigerator with an improperly adjusted or partially plugged burner can produce enough carbon monoxide to kill the occupants of a cottage or house in one night. Symptoms of carbon monoxide poisoning include nausea, headaches and dizziness. RECEIVE CASH FOR YOUR SERVEL REFRIGERATOR. The CPSC has arranged for you to receive $100.00 in exchange for your old Servel refrigerator. Call the Servel Hotline toll-free at 1-800-782- 7431. Operators are standing by 24 hours a day to answer your questions and make arrangements for a qualified propane dealer to remove the refrigerator from your home or cottage at no cost to you. REPRESENTATIVES ARE STANDING BY. If you have a Servel gas fueled refrigerator, call the toll-free number, 1- 800-782-7431, or write to: Servel Rebate, P.O. BOX 14874,Cleveland, OH, 44114." I would like to expand on this notice and briefly talk about carbon monoxide and the proper use of gas appliances. Carbon Monoxide The above mentions of the dangers of carbon monoxide poisoning which is easily misunderstood. Carbon monoxide is colorless, odorless and non-irritating gas. It is formed during incomplete combustion of carbon or carbon containing substances. Carbon monoxide is an insidious poison. It produces only mild symptoms of headache, nausea and can cause unconsciousness before the person can prevent it or knows what is happening. Irregular breathing, ringing in ears, seeing spots and dizziness are some of the other symptoms. Only 1000 parts per million of carbon monoxide or 0.10 percent in air can be fatal. 4000 parts per million (0.4 % in air) are fatal in exposures of less than an hour. Sometimes the above symptoms can be miss diagnosed as the flu. Continued low exposure over a period of time will cause an accumulation of carbon monoxide poisoning. Cases do occur where a person would stay home because of illness only to become progressively worse because of the additional exposure time to low levels of carbon monoxide. First Aid If a person shows evidence of carbon monoxide poisoning, immediately get that person into fresh air. Next lay the person down and give artificial respiration if necessary. Call the fire department and doctor for oxygen and treat for shock. Gas Appliances Many alternate energy folks are quite creative in the use of gas appliances. Since many of these folks are curious and challenged by do it yourself home brew concepts, a better understanding of gas equipment is called for. As with any tool, electrical device or gas appliance, improper use and operation will cause a safety hazard. Sometimes a person will service gas appliances themselves thinking that it is a simple device that can be easily fixed and checked. A little knowledge of gas appliances can be very dangerous when someone tries to service them or worse yet, perform modifications for greater efficiency. Gas Appliances are complex devices that appear to be very simple. Commonly, the operating principles of a gas appliance are not completely understood. Consult with a gas appliance professional or the appliance's manufacturer before servicing or adjusting gas appliances. There are specific safety devices in gas appliances that must not be modified. I have seen some home-made devices and ill-qualified repairs that are dangerous. Modifications of gas equipment should be approved by the manufacturer and meet the American Gas Association testing lab standards. If a hazardous condition is suspected with a gas appliance, the local gas utility in most cases, will come out free of charge for a safety check. Gas appliances should be cleaned, adjusted and safety checked at least once a year. Proper Venting The proper venting of gas appliances is very important. If a gas appliance is not vented properly, carbon monoxide can be easily produced. I have seen makeshift venting arrangements that are very dangerous and have refused to stay at that household. The flue system must vent to the outside in a proper manor and must meet code. Flue pipes are not to vent outside through a wall unless it is designed to do so by the manufacturer. A simple test can be utilized to determine if a gas appliance is venting properly. It is performed by placing a lighted match at the draft diverter when the appliance has been operating for a few minutes. If the draft diverter is spilling products of combustion, the match will blow out or the flame will be pushed downward and away from the draft diverter. This indicates a serious venting problem that must be corrected immediately. This test is not intended as a substitute for a complete chimney inspection, but will identify an immediate venting problem. Knowing the condition, proper design and operating characteristics of a chimney is always required for utilization of gas equipment. Wood Stoves And Chimneys Adding a wood stove to an existing flue pipe that is connected to a gas appliance is against the National Fuel Gas Code and other regulatory agencies. A wood stove or fireplace must have its own flue pipe. All flue pipes must be clean and in good repair without any restrictions. Chimneys must be of the proper height in relation to the roof of the house. If a liner is not present or the existing one is broken or over sized for the application, it must be repaired, relined or replaced. Medium Efficiency Gas Equipment In most cases, medium efficiency gas equipment requires the existing chimney to be relined with a stainless steel liner to prevent excess condensation. Excess condensation will lead to the premature deterioration of a chimney. Check with the local gas utility and manufacture when medium efficiency gas equipment is used. Flame Characteristics The flame characteristics of a gas appliance is very important. It must have a blue color without lifting off the burners and be of a size that does not impinge on the heat exchanger. A yellow flame indicates a serious problem that requires immediate attention because it will cause the formation of black soot in the gas appliance and chimney. Black soot must be cleaned out before the repaired appliance is put back in operation. Lines of soot on the exterior surfaces of an appliance is a clue that indicates a serious problem. All of the above conditions usually prevent the completion of the combustion process and will produce carbon monoxide. Conclusion The performance, maintenance, repair, installation and theory of operation of gas appliances are rather complex and should be performed by a professional or under the direction of a professional. If you do it yourself have it checked by a professional before the appliance is put in operation. At least once a year every gas appliance and chimney must be inspected, cleaned and adjusted if necessary. Any modification must be have the approval from the manufacturer and the American Gas Association. If you have a Servel gas refrigerator, call the hot line. Access Jim Lambesis, Middle Fork Engineering, 621 Dalton, Northbrook, IL 60062