Amtrol OWB Series - Manual (Page 30)

8. COMBINATION HEATING/COOLING SYSTEM WITH CHILLED WATER
The chiller must be piped in parallel with the boiler and isolation valves installed to
prevent the chilled water from circulating through the boiler and heated water from
circulating through the chiller. See Figure 25.
S
Insulation
Valve # 4
Chiller
Circulating Pumps
Flow Check
Return from System
Insulation Valve # 3
Insulation Valve # 4
Supply to System
R Cold Water Feed
Drain Cock
Note:
1.
When in cooling mode isolation valves 1 and 2 must be closed and valves 3 and 4 open.
2. When in heating mode isolation valves 1 and 2 must be open and valves 3 and 4 closed.
Figure 25.
9.
SINGLE BOILER PIPING WITH BLEND PUMP
When burner is operating the water flow throughout the boiler shall be not less than
1.8 GPM for each 100,000 BTU/HR of gross boiler output. Size blend pump
accordingly. See Table 3
Blend Pump Primary/Secondary
Pump
Boiler Model GPM GPM
OWB-9
OWB-15
OWB-25
OWB-35 16.3 78.9
OWB-50 19.6 94.9
Maximum water flow resistance for boilers is 14” w.c
Table 3.
30
Installation, Operation, And Service Instructions