Bell & Gossett P86272B VS Variable Speed Pump Control - Manual

Model VS Variable Speed Pump Control
SAFETY
INSTRUCTION
This safety alert symbol will be used in this manual to draw
attention to safety related instructions. When used, the safety
alert symbol means
ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED! FAILURE TO FOLLOW THESE
INSTRUCTIONS MAY RESULT IN A SAFETY HAZARD.
INSTALLER: PLEASE LEAVE THIS MANUAL FOR THE OWNER’S USE.
DESCRIPTION
The VS is a hydronic heating control. The temperature of the
heating water is controlled by regulating the speed of a pump
which injects water from a hot boiler loop (Primary loop) into a
cooler heating loop (Secondary loop). As the speed of the
pump increases, more hot water is sent into the Secondary
loop, and the temperature of the heating water increases.
The VS can be used as an outdoor reset control. When the
outdoor temperature falls below an adjustable start point, the
heating system is activated. The temperature of the Secon-
dary loop water is then automatically regulated based on
outdoor temperature. The outdoor reset function maintains
constant and comfortable ambient building temperature in all
weather conditions.
The VS can also be used as a set point control. In this mode of
operation, the VS will control the pump speed to hold a con-
stant temperature (determined by the user) in the Secondary
loop. The outdoor start temperature can be set to ON so the
set point will be held regardless of outside temperature.
The VS is equipped with a Primary loop sensor. This sensor
monitors the temperature of the boiler return water. If the
boiler return water falls below an adjustable temperature, the
VS can be configured to slow down the speed of the injection
pump to help the boiler return water temperatures recover.
The VS can be enabled or disabled from a standard thermostat
or switch, or the VS can reduce the temperature of the heating
loop water when the building is not occupied or when
occupants are sleeping.
INSTRUCTION MANUAL
P86272B