Current through Register Vol. 35, No. 18, September 24, 2024
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.