Section 658-110-21 - Welding of non-residential warm air Heat exchangers1. The manufacturer shall be consulted to determine whether the welding of a heat exchanger is sound engineering practice. The manufacturer shall provide a written statement as to the feasibility of its heat exchanger being welded. If the heat exchanger is no longer in production, a master licensee shall make a written request to the Board and obtain written approval from the Board before the repair is undertaken.2. The repair of a heat exchanger by welding shall be performed by a welder in a procedure suitable for the material. A master licensee shall oversee such repairs.3. The master licensee shall receive guidance from the welder as to the feasibility and acceptability of performing the welding procedure of the metals prior to the repair of any heat exchanger.4. After completion of said repairs or welding, the master licensee shall obtain a written statement from the welder documenting that the heat exchanger has been welded, tested and is acceptable for use without leakage of after-products.5. Written documentation of said repairs or welding shall be provided to the owner. The original documentation shall be kept on file by the master licensee who requested the welding. A copy of all the repair documents containing, at a minimum, the following information shall be sent to the Board: A. The name of the owner and location where the repairs were completed;B. The name and address of the welder;C. Specific area(s) or location(s) where the repair(s) or welding was performed;D. Written approval of the repair from the manufacturer where applicable;E. Equipment identification information, i.e., name, model number, serial number and gross Btu. rating; andF. The name, address, and license number of the master licensee who requested the repair.6. Welding repair of a heat exchanger may be performedonly once. A subsequent welding repair may not be made to a heat exchanger unless a master licensee makes written request to the Board and obtains written approval from the Board before the repair is undertaken.02-658 C.M.R. ch. 110, § 21