47
8.7 Indirect Storage Tank
Boiler GMHB125 can be electrically connected to indirect
storage tank as follows:
• Connect DHW priority sensor
10k Ω
NTC to terminals
9-10
on terminal block
M2
.
• Insert
10k Ω
NTC sensor element in the sensor well of
indirect storage tank.
• Verify exchange capacity of the storage boiler coil is
appropriate for boiler power.
• Adjust DHW tempe95 °F to +140 °F (+35 °C to
+60 °C) by rotating left knob on boiler Control.
IMPORTANT: set parameter P03 as described in:
"PARAMETER SETTINGS".
8 - ELECTRICAL CONNECTIONS
Note
Sensors supplied for this boiler are
proprietary to the manufacturer. Use of
alternate sensors
WILL
diminish boiler
performance.
SUPPLY Cord
120V/60HZ
BOILER CONTROL
10k Ω
DHW
Indirect Tank
Sensor
or
DHW Indirect
Tank Aquastat
(Heating Only
Boilers
DO NOT
USE
1K
Ω
Outdoor Reset Sensor
Zone Control
T-Stat
Use of Indirect Storage Tank (DHW):
☐
Use either
10k Ω
DHW sensor or Indirect Tank Thermostat
to interface with boiler. Wire to M2 terminals #9 and #10.
☐
Use of booster pump to increase flow rate to indirect tank
is not recommended by manufacturer. (Model 125 only).
See Figure 8-9.
☐
Locate tank as close to boiler as possible (within 5 ft.).
☐
Size DHW tank, piping, and system to use only internal
boiler pump.
☐
Change P03 on boiler for application as specified on the
wire diagram and Boiler Control section of Installation,
Operation & Maintenance Manual supplied with the boiler.
FIGURE 8-9 KT INDIRECT STORAGE TANK (MODEL
GMHB125)
A
Heating system
B
Three way diverter valve
C
Heating water flow
D
Heating supply to DHW indirect storage tank coil
E
Heating water return
F
Tank
G
Optional DHW priority sensor tank
*GMHB125 Model shown -
10K
Ω
Sensor
A
G
PN 240012363 REV. B [03/29/2019]
