Laars Pennant PNCH Installation And Operation Instructions Manual page 16

Page 16
SYSTEM
RETURN
PUMP LOCATION FOR
NON-PUMP-MOUNTED UNITS
CAUTION: THIS DRAWING SHOWS SUGGESTED
PIPING CONFIGURATION AND VALVING, CHECK
WITH LOCAL CODES AND ORDINANCES FOR
ADDITIONAL REQUIREMENTS.
LEGEND
THERMOMETER
PURGE
TEMPERATURE
VALVE
SENSOR
GLOBE VALVE
CHECK VALVE
PRESSURE REDUCING VALVE
W/ FAST FILL BYPASS
Figure 5. Hydronic Piping — Multiple Boilers, Low Temperature System.
C
B
A
T1
PUMP LOCATION FOR PUMP-MOUNTED UNITS
PRIMARY/SECONDARY MANDITORY FOR ALL
VARIABLE FLOW SYSTEMS
INSTALL AIR VENTS AT HIGH POINTS IN SYSTEM
PIPING & SIZING OF EXPANSION TANK
PER TANK MANUFACTURER'S INSTRUCTIONS
EXPANSION TANK
DIMENSION "C" (COMMON PIPING) TO BE FOUR
WITH AIR SCOOP AND
PIPE DIAMETERS, MAX. (NO ELBOWS OR VALVES)
AUTO AIR VENT
BOILER CIRCUIT PIPING MUST BE EQUAL
TO BOILER WATER CONNECTION SIZE
3-WAY VALVE
BOILER CIRC. PUMP SIZED FOR FLOW THROUGH BOILER
DOTTED DEVICES INDICATE ALTERNATE LOCATIONS
VALVE
PUT BOILER CONTROL SENSOR IN THE SYSTEM
SUPPLY WHEN USING THIS PIPING STYLE.
PUMP
MINIMUM BOILER INLET WATER TEMPERATURE
MUST BE AT LEAST 120°F.
LAARS Heating Systems
COLD WATER
MAKE-UP
C
SYSTEM PUMP
B
A
ADJUSTMENT PROCEDURE TO MAINTAIN
120°F INLET TEMP:
1. Turn on boiler and open valves A & B.
2. After steady-state operation, if T1 is less than
120°F, slowly close valve B until T1 climbs to
120°F.
3. If T1 is greater than 120°F, slowly close
valve A until T1 drops to 120°F.
4. Check after system operating temperature
has stabilized. Make final adjustments.
T1
SYSTEM
SUPPLY