15
MB Pool & spa heater
GAS SUPPLY CONNECTIONS
Gas piping must have a manual shut-off valve located
outside the heater jacket. All gas piping should be
tested after installation in accordance with local
codes.
CAUTION: The heater and its manual shut off valve
must be disconnected from the gas supply during
any pressure testing of that system at test pressures
in excess of 150mbar (2.2psi). Dissipate test pres-
sure in the gas supply line before reconnecting the
heater and its manual shut off valve to gas supply
line. FAILURE TO FOLLOW THIS PROCEDURE
MAY DAMAGE THE GAS VALVE. OVER PRES-
SURED GAS VALVES ARE NOT COVERED BY
WARRANTY. The heater and its gas connections
shall be leak tested before placing the appliance in
operation. Use soapy water for leak test. DO NOT
use open fl ame.
NOTE:
Do not use PTFE tape on the gas line pipe
thread. A fl exible sealant is recommended.
Models 055 and 105 are fi ttef with a ½" BSP gascock,
all others have a ¾" gascock.
A minimum of 20 mbar (8”) WG and a maximum of
22 mbar (8¾”) W.G.upstream pressure under load,
and no load conditions are provided for natural gas or
a minimum of 37mbar (14¾”) W.G.and a maximum
of 45 mbar (18”) W.G for propane gas.
GAS PRESSURE
For LPG Heaters the gas pressure is regulated
by the injectors fi tted in the factory. There is no
adjustment.
For NG Heaters the regulator on the gas valve is
factory set. If adjustment is required, remove the
cap and turn the adjustment screw clockwise to
increase and counter-clockwiese to decrease the
burner pressure.
Honeywell Gas Valve
Burner Pressure
adjustment
PIPE SIZING FOR GAS CONNECTIONS
MAXIMUM EQUIVALENT PIPE LENGTH METRES
N - NATURAL GAS @ 1.0 mbar PRESSURE DROP
P
- L.P.G. @ 2.5 mbar
PRESSURE DROP
10mm 15mm
22mm
28mm
MODEL
N
P
N
P
N
P N
055
6
12
15
105
3
5
20
155
10.5 >24 36
185
8
>24
29
265
4.5
18 14.5
a
405
8.5
7