N.M. Admin. Code § 14.12.5.18

Current through Register Vol. 35, No. 21, November 5, 2024

Section 14.12.5.18 - MANUFACTURED HOME CONNECTED TO NATURAL GAS (NEW OR USED; PRE-OWNED OR RESOLD)

The following requirements apply to the installation of new, used, pre-owned or resold manufactured homes, unless otherwise indicated.

A. General requirements. The fuel supply system installation and connection for a manufactured home produced under the Federal Manufactured Home Construction and Safety Standards Act shall comply with the manufacturer's installation instructions.

B. Testing procedures. The gas system must be tested for leaks after completion at the site. The fuel supply system testing shall be completed in accordance with the manufactures testing instructions.

C. Used, pre-owned and resales. If the manufacturer's installation instructions are not available for a used or pre-owned or resold manufactured home, the following requirements apply:

(1) Gas connections.

(a) No riser, inlet or gas connection or inlet gas connection shall be located beneath any manufactured home or any exit. No manufactured home shall be installed over a gas yardline.

(b) The gas inlet on the manufactured home shall protrude no more than six (6) inches from the manufactured home. The inlet shall be rigidly anchored or strapped to a structural member within six (6) inches of the point where it enters beneath the manufactured home.

(c) The gas riser shall be located within twenty-four (24) inches of the manufactured home.

(d) The size of the gas connections shall not be less than three-quarters (3/4) inch I.D. standard iron pipe size; or the connector shall be the same size as the inlet.

(e) The main gas connection shall be doped and shall be an approved flexible-type connection. Approved connectors are:

(i) flex connectors: the maximum length for flex connectors is thirty-six (36) inches; a list of approved flex connectors is maintained by the division;

(ii) black or galvanized malleable iron pipe and fittings may be used to construct a double- swing joint; this connection requires the use of elbows, unions and nipples constructed in such a manner as to allow the connection to give without breaking in all of the three (3) dimensions that a shifting unit might move; no elbows that are used in the double- swing joint shall be beneath the manufactured home;

(iii) all fittings and nipples except unions used in the gas piping system of a manufactured home must have tapered threads.

(f) Any copper tubing used for natural gas must be annealed type grade K or L, internally tinned.

(g) Gas shut off valves shall be installed on each natural gas riser at a height at not less than four (4) inches above grade. The shut-off valve shall be located between the on-site utility terminal and the outside flexible connector of the manufactured home.

(h) All materials used for the installation, extension, alteration or repair of any gas piping system shall be new and free from defects or internal obstruction. Inferior or defective materials shall be removed and replaced with acceptable materials.

(i) Ratings of gas appliances are based on sea level operations. Appliance ratings shall be reduced at the rate of four percent (4%) for every one thousand (1,000) feet above sea level for appliances above two thousand (2,000) feet.

(2) Exterior gas piping. All gas piping beneath a manufactured home shall be adequately supported by galvanized, or equivalently protective metal straps or hangers at least every four (4) feet, except, where adequate support and protection is provided by structural members.

(a) Gas shut-off valves shall not be placed beneath a manufactured home.

(b) Any extensions or alterations made to the gas piping system for the purpose of establishing the supply inlet for connection to the riser may not reduce or restrict the gas piping size from that of the original inlet.

(c) There shall be only one point of crossover between the sections of a multi-wide manufactured home which must be readily accessible from the outside.

(d) The connector used for the crossover on multi-wide manufactured homes when gas is supplied to more than one (1) section, must be made by a listed "quick disconnect" device, which shall be designed to provide a positive seal of the supply side of the gas system when such device is separated.

(e) The crossover connection shall be of the same size as the piping with which it directly connects.

(f) When the gas riser is located on the opposite side of the manufactured home from the supply inlet, the gas piping may be run under the home in compliance with Paragraph (2) of Subsection C of 14.12.5.18 NMAC.

(g) All exterior openings shall be sealed to resist the entrance of rodents.

(3) Interior gas piping. Each gas-fired appliance must have a listed shut-off valve located within three (3) feet of the appliance and located in the same room as the gas appliance. Appliance connectors shall not exceed three (3) feet in length, except for range connectors, which shall not exceed six (6) feet in length.

(4) Bond of gas piping.

(a) Gas piping shall not be used as an electrical ground.

(b) Gas piping shall be bonded. Metallic gas piping shall be considered bonded if it is connected to the terminal on the chassis of the manufactured home by clamps, solderless connectors or by suitable ground-type straps.

(5) Pressure tests.

(a) Before the gas supply may be turned on, each manufactured home must pass a pressure test at the installation site.

(b) Before appliances are connected, the piping shall withstand a pressure test of at least six (6) inches mercury or three (3) PSI Gauge for a period of not less than ten (10) minutes without showing a drop in pressure. Pressure shall be measured with a mercury manometer, slope gauge or equivalent device calibrated to read in increments of not greater than 1/10 pound. The source of normal operating pressure shall be isolated before pressure tests are made. The temperature of the ambient air on the piping must remain constant throughout the test.

(c) After the appliances are connected, the piping system must be pressurized to not less than the pressure the supplier furnishes to the manufactured home's piping. All appliance connections shall be checked for leakage.

N.M. Admin. Code § 14.12.5.18

14.12.5.18 NMAC - Rp, 14.12.2.47 NMAC, 14.12.2.48 NMAC, 14.12.2.49 NMAC, 14.12.2.50 NMAC & 14.12.2.52 NMAC, 12-01-10