Pump Connection - Takagi T-M50 ASME Installation Manual And Owner's Manual

The T-M50 can be used to control a recirculation pump. Proper pump control helps to preserve
the life of the system and saves energy as well. The T-M50 pump control port is a "normally-
open" dry contact, and therefore needs additional components to properly control a recirculation
pump. To control the recirculation pump, connect the pump to the pump terminal in the T-M50
as shown in the diagram below. (In a multi-unit system, connect the pump ONLY to the
MASTER unit.) The pump is to be connected using suitable relays shown in the diagram below
(the pump terminal is essentially only a dry contact. An external power supply and relays
are required to operate the pump). Please make sure the relays are properly rated for the
recirculation pump.
Using the T-M50's internal thermistors as a temperature control, the recirculation pump will only
turn on when recirculation is needed.
CAUTION
In a multi-unit system, the pump must be connected to the pump terminal in the MASTER
unit only. If the pump is connected to any of the SLAVE units, the pump will not work.
These components are not included
with Takagi water heaters and are
external to the unit. They must be
acquired separately.
Connect to this terminal.
This is the pump terminal.
PUMP CONNNECTION
Power supply for relay
- 22 -
Power supply for pump
AC120V
AC220V etc
AC120V
AC220V etc
for relay
Thermal relay
Recirculation
pump