Benchmark Pump Relay - Watts Aerco BENCHMARK 750 User Manual

Benchmark 750 – 1000 Boiler User Manual - INTERNATIONAL
Installing Sequencing Isolation Valve – Continued
2. The Heating Boiler's shell harness has one unused cable. One end of this cable is
connected to the DELAYED INTERLOCK IN terminals in the I/O board (see Figure 2-14)
while the other end contains a Molex connector with a jumper wire inserted in it (this
jumper wire allows units that do not have a sequencing isolation valve to operate
normally). Find the free end of this cable inside the unit's enclosure.
Figure 2-14: Sequencing Isolation Valve Installed
3. Remove the jumper wire from the Molex connector and then plug it into the sequencing
isolation valve's connector.

2.15 BENCHMARK PUMP RELAY

Benchmark 750 and 1000 models ship with a pump relay (P/N 69102-3) as standard equipment.
The pump relay allows the user to turn a pump on/off and open/close a motorized valve as the
boiler cycles on and off on demand. The Pump Delay Timer feature allows the user to keep the
pump running and keep the motorized valve open for up to 30 minutes after the boiler has shut
down and the demand is satisfied. See Figure 2-15 and 2-16 for wiring details.
The pump relay is attached to the outside of the power box. Older units may or may not include
the pump relay. Boilers equipped with the pump relay have a label on the power box cover
adjacent to the relay.
PUMP RELAY
Page 32 of 170
11/03/2016
CHAPTER 2 – INSTALLATION
Figure 2-15: Pump Relay Location
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Ph.: 800-526-0288
POWER BOX
OMM-0119_0A
GF-130-I