Kirk, J.
In this action of tort the plaintiff alleges that the defendant, its agents or employees negligently “serviced” an air conditioner in the plaintiff’s premises, and as a result of the defendant’s negligence the air conditioner burst into flames, causing damage to the plaintiff’s property from fire and smoke. The case comes to us on the defendant’s exception to the denial of its motion for a directed verdict at the close of the plaintiff’s, evidence.
The only witnesses for the plaintiff were two of its employees. Their testimony is summarized as follows. The plaintiff corporation operates a wholesale dress business catering to small retailers. There were two afr conditioners in its showrooms located on the fifth floor of a building owned by the plaintiff at 75 Kneeland Street, Boston. On August 2, 1965, one of the witnesses, a sales employee of the plaintiff, noticed that one of the air conditioners was not functioning properly. She notified her superior, the other witness for the plaintiff, ■ who called the defendant, with whom the plaintiff had a service and maintenance contract covering the air conditioners. A repairman from the defendant arrived at the plaintiff’s showrooms about 9:30 a.m. Both witnesses observed the repairman take the grill from the bottom of the unit. The sales employee remained in the showrooms while the repairman worked on the air conditioner, but “did not pay any particular attention to what he was doing,” other than to notice that he removed the grill and did not work on any other section of the unit. The repairman left about 10:30 a.m. Two hours later the employee smelled smoke and then saw flames shooting forth from the bottom of the air conditioner that the repairman had been working on. She immediately called the fire department.
Following the denial of the defendant’s motion for a directed verdict the jury returned a verdict for the plaintiff in an amount which the parties agreed represented the damage sustained by the plaintiff.
The defendant contends that the evidence of the plaintiff was insufficient to warrant submission of the case tp the jury. We must agree. The only evidence linking the defendant with the fire was the testimony by the plaintiff’s employees that one of the defendant’s employees was working on the air conditioner and that it burst into flames two hours after he had left the premises. No evidence of what the repairman did to the air conditioner was introduced, nor was there any indication of what had originally caused the machine to malfunction. There was no direct evidence of the cause of the flames. There was not only a complete absence of expert opinion testimony but it seems to us a lack of evidence establishing facts upon which an expert opinion could be predicated. The jury were thus left “to conjecture and surmise” about the cause of the fire, “with out adequately founded . . . essential, expert guidance.” Stewart v. Worcester Gas Light Co. 341 Mass. 425, 435. Kenney v. Sears, Roebuck & Co. 355 Mass. 604, 608. Dolan v. Suffolk Franklin Sav. Bank, 355 Mass. 665, 669-670. The cause of the fire was not susceptible of determination by the jury’s “general knowledge of practical affairs.” Cf.
Toppin v. .Buzzards Bay Gas Co. 348 Mass. 397, 401. It follows that the defendant’s motion for a directed verdict should have been allowed.
Exceptions sustained.
Judgment for the defendant. ■
A count in contract was waived by the plaintiff.