Nevertheless, there must exist in the first place a fire, which is the effect of combustion, and is equivalent to ignition or burning. See id; see also Spare v. Glens Falls Ins. Co. 137 Conn. 105, 110 (1950) ("the results of smoke and heat, where there is no ignition outside the agencies employed, are not covered by the policy, nor is damage by any degree of heat alone without flame or glow covered."). Although the Supreme Court of Connecticut in Spare focused on the issue of a "friendly fire," that is, one intentionally built, discussion of the flame or glow requirement aligns with consensus across jurisdictions.

The only case which considered excessive heat constituted a hostile fire is O'Connor v. Queen Insurance Co., 140 Wis. 388, and recent decisions have not followed it. Only last year the whole problem of overheated oil burners causing damage by excessive heat was reconsidered in Connecticut and Massachusetts and it was held that they were friendly fires not covered by the fire insurance policies. Spare v. Glens Falls Ins. Co., 137 Conn. 105; Wasserman v. Caledonian-American Ins. Co., (Mass.), 95 N.E.2d 547. These cases state the rule as it exists today and as it has been in the United States for more than a half century. Way v. Abington Mutual Ins. Co., 166 Mass. 67; Patterson, Insurance Law During the War Years, 46 Col. L. Rev. 345, 362.

It is recognized, however, that there are several decisions in other jurisdictions holding that although a fire contained in a furnace becomes excessively hot due to the malfunctioning of a thermostat or other cause, it continues to be a friendly fire until it breaks from the container and damages adjacent property. ( First Christian Church v. Hartford Mut. Ins. Co., 38 Tenn. App. 482; Consoli v. Commonwealth Ins. Co., 97 N.H. 224; Mitchell v. Globe Republic Ins. Co., 150 Pa. Super. 531; Spare v. Glens Falls Ins. Co., 137 Conn. 105.) The rationale of these cases has been described as the "spatial relationship" (3 B.C. Ind. Comm. L.R., 15, 23) in that "the insured expects that the process of combustion will take place within certain limits.

" The case of Spare v. Glens Falls Ins. Co., 137 Conn. 105, 75 A.2d 64, 65, involved a situation similar to that presented by the instant record. Said the Court: