1. The part against the defendant in the judgment of the first instance is revoked.

2. The plaintiff's claim against the defendant is dismissed.

3...

1. Basic facts

A. The Plaintiff is a company that sells and manufactures air conditioners, and the Defendant is a company that conducts civil engineering works, and D (hereinafter “D”) is a company that conducts construction works.

B. D was awarded a contract from E on January 24, 2017 for the Glateral Work on the 2nd floor F in Daegu-gu, Daegu-gu (hereinafter “instant interior Works”).

C. The Plaintiff: (a) performed the installation of cooling and heating equipment (hereinafter “instant construction”); (b) the Plaintiff’s employee H as a party to the instant construction work with I, the actual representative of the Defendant, who was in charge of the said construction site, entered into a goods additional contract (hereinafter “instant contract”) on January 3, 2017, stating that the construction cost shall be KRW 13,200,000 (including value-added tax) with respect to the said construction work; and (c) on March 2017, the Plaintiff completed the installation of cooling and cooling equipment at the instant construction site.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1, 3, 9, Eul evidence Nos. 2 and 7, the purport of the whole pleadings

2. The Plaintiff’s assertion concluded a contract with the Defendant for the installation of air conditioners and received KRW 6,00,000 among the construction cost.

Therefore, the defendant is jointly and severally liable with the co-defendant C of the first instance trial to pay the construction cost of KRW 7,200,000 to the plaintiff and the delay damages therefor.

3. The fact that the plaintiff prepared the contract of this case with I, who is the actual representative of the defendant, is as mentioned above. However, the following circumstances are as follows: Gap evidence Nos. 4, 6, 7, and 10, Eul evidence Nos. 3 through 8 (including the serial numbers), Eul's testimony and the whole purport of oral argument, and Eul's testimony and oral argument as to the witness of the trial of the case. ① The installation of the heating and cooling machine, which is part of the tesen Corporation of this case, shall be carried out by Eul who has been awarded a contract for the tesen work, and the defendant or I shall run the tesen work of this case with D and the tesen work of this case. The only statement of evidence No. 10 as to Gap evidence No. 10 alone.