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MASTERTEMP
™
Pool and Spa Heater Installation and User’s Guide P/N 475106 Rev. D 1/2016
26
| Section
Heater Will Not Fire - A
Start
GO TO
“HEATER WILL NOT FIRE - B”
Page 27
Heater should fire on demand
for heat.
Check Fireman’s Switch circuit
connections (time clock, wiring,
external controller relay).
Remove jumper. Check wiring
between Transformer and J7
terminals on Control Board
and between J7 and
Fireman’s Switch on Terminal
Board, check fuse, and
restore continuity.
Restore power to heater.
Replace Transformer.
Heater should fire on
demand for heat.
Replace Control Board.
Replace Membrane Pad.
Check wiring connections
between power supply and
Junction Box and between
Junction Box and Terminal
Board; restore continuity.
Check wiring connections
between Terminal Board and
Transformer primary and
restore continuity.
Is green “SPA” or
“POOL” LED “on”
YES
NO
NO
YES
YES
YES
NO
NO
Depress “POOL” or “SPA” ON
button on Membrane Pad.
Does “POOL” or “SPA” LED
come on?
Check for line voltage to
heater.
Check for 24 VAC at sec-
ondary of Transformer.
Check for Line Voltage at
Transformer primary pins.
White connects to Pin 3 on
Transformer, Black to Pin 2,
Orange to Pin 1.
240V: check Pin1 to Pin 3.
Jumper Fireman’s Switch at
Terminal Board and depress
“POOL” or “SPA” ON button on
membrane pad. Does “SPA” or
“POOL” LED come “on”?
Leaving jumper in place,
check for 24 VAC between
Fireman’s Switch terminals
and ground.
Jumper pins 6 and 5 on J6 of
Control Board. Does “SPA”
LED come on?
Jumper pins 6 and 4 on J6 of
Control Board. Does “POOL”
LED come on?
Check for Line Voltage
between L1 and L2 terminals
on Terminal Board.
NO
YES
NO
NO
YES
YES
YES
YES
YES
NO
NO
YES
NO
Check that the 12-pin
plug is installed (red
240V)
If plug is not installed:
Install the 240V plug in
120V circuit:
Replace
transformer, control
board and ignition control
module (see "HEATER
WILL NOT FIRE-C and
-D", Pages 37 and 38).
Check fuse and all
other 24V components
for damage.
Remove jumper. Check ribbon
cable connection between
Membrane Pad and J6 on
Control Board. Depress
“POOL” or “SPA” On pad
again. Does “POOL” or “SPA”
LED come on?
NO
Section 3. Troubleshooting