Flow Switch Adjustment; Circulator Sizing; Near Boiler Piping Connections - Lochinvar KNIGHT 399 Installation & Operation Manual

6
Hydronic piping

Flow switch adjustment

Refer to Table 6A for the proper setting of the sensitivity
screw. For reference, the position of the screw prior to setting
should be turned clockwise with a Phillips driver until it stops
(FIG. 6-3). Proceed to turn the screw counterclockwise the
amount of turns listed in Table 6A based on the model.
Consult the manufacturer's instructions for wiring the flow
switch to your system.
Table 6A Paddle Size / Sensitivity Screw Adjustment
MODEL PADDLE SIZE
Note: Paddles are included with the flow switch.
399 #3
500 #3
600 #3
700 #3
800 #3
Turn the sensitivity screw clockwise to
NOTICE
increase the flow rate required to activate
the switch. Turn the sensitivity screw
counterclockwise to decrease the flow rate
required to activate the switch.
Figure 6-3 Flow Switch Adjustment
GROUND
COMMON

Circulator sizing

The Knight XL heat exchanger does have a pressure drop,
which must be considered in your system design. Refer to the
graphs in FIG's 6-5 and 6-6 for pressure drop through the
Knight XL heat exchanger.
36
SENSITIVITY SCREW
ADJUSTMENT
7½ turns
5½ turns
7¼ turns
5¼ turns
3¼ turns
NORMALLY
OPEN
SENSITIVITY
ADJUSTMENT
NORMALLY
CLOSED
Installation & Operation Manual

Near boiler piping connections

Figure 6-4A Near Boiler Piping w/Y-Strainer
SYSTEM PUMP
BOILER PUMP
Y-STRAINER
(RECOMMENDED)
Figure 6-4B Near Boiler Piping w/Low Loss Header
SYSTEM PUMP
SYSTEM SENSOR
AIR SEPARATOR
DRAIN
(TYPICAL)
AIR VENT VALVE
LOW LOSS HEADER
(TYPICAL)
Y-STRAINER
(RECOMMENDED)
DOMESTIC HOT
WATER PUMP
INDIRECT
DOMESTIC
HOT WATER
TANK
TO FLOOR
DRAIN
EXPANSION TANK
FAST FILL VALVE
INDIRECT
DOMESTIC
DRAIN VALVE
HOT WATER
TANK
TO FLOOR
DRAIN