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HydroBank MS Installation and Operation Manual MAMM-WSHP-IOM-1MSA (October 2014)
Motorized Shutoff Valve Option
Motorized Shutoff Valve Option
The motorized valve option is typically used in systems
that employ VFDs on the condenser water pumps.
When the space temperature set point is satisfied, the
unit shuts down and the valve closes. Pump power is
thus greatly reduced at reduced flows, resulting in sig-
nificant energy savings.
The motorized valve shuts off the water flow through the
unit when the compressor is off. The valve is a normally
open, power-close type and will open in the event of
power loss.
Figure 18: Motorized Valve Option
HP-5 Microprocessor Control
Features
•
Low and high voltage protection.
•
Check microprocessor at startup – self-diagnostic
•
Random start time delay from 5 to 35 seconds
•
Compressor anti-short cycle protection for 300 sec-
onds (5 minutes)
•
Compressor, fan and reversing valve control
•
Condensate overflow protection
•
Compressor lockout with selectable intelligent/
manual reset
•
LED status on the board
•
Lockout alarm signal to an LED in the wall thermo-
stat in the event of a safety circuit fault
•
Fan interlock to automatically energize the fan
whenever the compressor is on
•
Board operable on 50 and 60 cycle power
•
Emergency shutdown from a field-supplied signal
•
Unoccupied (night setback and night setup) mode
from a field-supplied signal.
•
Dry contact alarm signal for connection of a fault
signal to a DDC controller.
•
Auxiliary dry contact for tie-in of a motorized valve
when the compressor is on (or optional compressor
status)
•
Night heating or cooling operation from the wall
thermostat (compatible Mammoth thermostat
required)
•
Override of the unoccupied mode from the thermo-
stat for 2 hours (compatible Mammoth thermostat
required)
•
Low and high pressure compressor protection
•
Low pressure bypass with 0, 1, 2 and 3 minute
selections.
Operation
INITIAL POWER-UP: When power is applied to the con-
troller from unit’s 24-volt transformer, a “green” LED will
be illuminated and a 120 second time delay will occur
before the fan, reversing valve and compressor are able
to operate. The controller will perform a self-diagnostic
and voltage check.
Figure 19: HP-5 Microprocessor Board
LOSS OF POWER: On a loss of 24-volt power to the
board, all the outputs are de-activated. On return of
power, a 120 second time delay will occur before the
fan, reversing valve and compressor are able to oper-
ate. After 120 seconds, the fan, reversing valve and
compressor are able to operate after a short time delay.
