MasterTemp Pool and Spa Heater P/N 474131 Rev. M 8/2020
34
Figure 31.
REMOTE CONTROL CONNECTIONS
1. Switch off power to heater at main circuit breaker panel.
2. Unbolt and remove the access door panels.
3. Open control box cover (see Figure 31).
4a.
To connect a 2-Wire Control (such as IntelliTouch
™
or EasyTouch
™
control systems)
or a timer:
- Remove the factory installed jumper from the Fireman’s Switch terminals.
- Connect wires between the Fireman’s Switch terminals on the heater and the relay.
Connect wires from the controller or timer to the Fireman’s Switch. Controller,
timer or relay should be sized to handle 24VAC at 0.5 Amp (because it will be
completing the 24VAC control board circuit on the heater as shown in Figure 24).
DO NOT apply line voltage to the Fireman’s Switch terminals. Use 18 gauge wire
with a minimum 1.2 mm (3/64 in.) thick insulation rated for a temperature rise of
at least 105° C.
- Knock-outs are provided to route the wires through the bottom of the control box and past the junction box.
4b.
To connect a 3-Wire Control:
- Connect wires between the control board terminals on the heater and the external relays, as shown in Figure 32
below. Use at least 2 relays per heater, to allow for
an “OFF setting” on each heater mode. Select relays
that can handle logic level switching. DO NOT apply
line voltage to control board terminals.
- Move jumper (as shown on page 38) to enable external
control and to disable the heater membrane pad’s
“Pool ON” and “Spa ON” buttons (the “OFF” key
on the membrane pad remains functional).
- Knock-outs are provided to route the wires through
the bottom and the top of the control box and past
the junction box.
5. Close control box cover.
6. Re-install the access door panels.
To control heaters that are operated in parallel, connect
wiring at same locations on heater as 2-Wire or 3-Wire
Control. It is imperative that each control circuit is isolated
from the other control circuits, to avoid that current will
flow from one heater to another through the control circuits.
NOTICE: The fuse for the Fireman’s Switch is a 1.25 Amp
31.75 mm x 6.35 mm fast blow fuse, which is commonly
available.
GND
L1
GR
OUND (GND
)
L2
JUNCTION
BO
X
L1
L2
BM
FL
F1
L1
TRAN S
F
I
R
E
M
A
N
S
S
W
I
T
C
H
Fireman's Switch
Completes the heater
24 Volt AC Control
Board Circuit.
DO NOT connect this
circuit to Line Voltage!
Y Y
R
W
G/
Y
Y
Y
TERMINAL BOARD
TRANS
TRANS
FUS
E
FUS
E
L2
Time Clock or Remote
(Purchase Separately –
Supplies Power to
Circulator Pump)
24VAC
24 VAC
BK
O
O
BK
W
R
BR
BL
W
12 Pin Receptacle
VA
L
TH IN
D
GND
24
VA
C
24
VA
C
FS
THERMIS
TO
R
OPERATING CONTROL
DISABLE TOGGLE
ENABLE TOGGLE
MEMBRANE PAD
CONNECTION
9
1
J6
Figure 32.
Section 1. Installation
