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The dark squares indicate the direction
the dipswitches should be set to.
PUMP CONTROL MODE
The T-M50 provides the four types of the pump control modes. The pump control modes are
selected by changing dipswitch settings. The dipswitches are located in the
upper bank
of
dipswitches in the lower-left quadrant of the central computer board in the T-M50. (See picture
below)
A) No. 4 ON: Recirculation Control
This mode is for providing hot water as soon as possible like a recirculation usage. The pump
is only made to run while the temperature of the water in the re-circulation loop is not close to
the set temperature of the T-M50. The pump will run for about 1 minute every 30 minutes to
determine whether or not the water temperature in the whole recirculation loop is lower than
9°F from the set temperature. If the water temperature is lower than 9°F from the set
temperature, the pump will remain running until the water in the loop gets up to the set
temperature. If not, the pump will stop for another 30 minutes. If the inlet thermistor senses
that the water temperature is lower than 9°F from the set temperature before those 30 minutes
have elapsed, the pump will activate immediately and remain running until the water in the
loop gets up to the set temperature.
B) No.5 ON: Storage Tank Circulation Control
The T-M50 will heat the water 5.4°F higher than its set temperature (unless the T-M50 is
already set at its maximum temperature of 185°F). This is to ensure a higher rate of recovery
for storage tank applications. The circulation pump (from storage tank to T-M50) will always
remain on.
C) No.4 and No.5 ON: Energy Conserving Recirculation
This pump control mode is similar to the “Recirculation Control mode”. However, once the heat
requirement is less than 7,440 BTU/h, the pump will turn off. The pump will activate again
when the temperature of the system is less than 95°F or after 20 minutes have elapsed from
its previous operation.
*If operating the pump in this mode, insulation is recommended on the water piping.
D)
No.4 and No.5 OFF: Normal Control (Default setting)
This provides no ON/OFF control for the pump. If a pump is connected to the pump control
terminal and both No.4 and No.5 are OFF, the pump will be made to run all the time as long as
there is a power supply to the T-M50 (If the temperature remote controller, the TM-RE30, is
installed, the pump will stop when the remote is turned off). Water in the loop will be
maintained at set temperature.
O
N
1 2 3 4 5 6 7 8
RE
-CIR
STOR
AGE
P-RE
LP
D-PRT
B) Storage Tank
Circulation Control
A) Recirculation
Control
C) Energy Conserving
Recirculation
D) Normal Control
Pump control modes
(Default)
O
N
1 2 3 4 5 6 7 8
RE
-CIR
STOR
AGE
P-RE
LP
D-PRT
O
N
1 2 3 4 5 6 7 8
RE
-CIR
STOR
AGE
P-RE
LP
D-PRT
O
N
1 2 3 4 5 6 7 8
RE
-CIR
STOR
AGE
P-RE
LP
D-PRT
Upper bank of
dipswitches