Raypak B0507 - Page 16

CONNECTIONS – PLUMBING
16
PIPE SIZES
The pipe sizing for water heating and mechanical heating systems should be carried out by persons competent to
do so, choosing the most suitable pipe size for each individual application. Reference to the technical specifications
of the water heater and local regulatory authority requirements must be made.
The table below provides indicative pipe and pump sizes between Raypak unit/s and storage tank/s for typical
water heating installations using storage tanks (DHW).
PUMP SELECTION AND PIPE SIZE
Model
Pump
Branch Size
Minimum Manifold Header
Size Required (mm)
UPS
Series
Speed
TP Series
inches
mm
1
Unit
2
Units
3
Units
4
Units
507
32-80N
3
1¼
32
50
65
65
65
538
32-80N
3
1¼
32
50
65
80
80
658
32-80N
3
1½
40
50
65
80
80
768
32-80N
3
50-30/4FB
2
50
80
100
100
100
40-60/2B
2
1½
40
50
80
80
80
868
32-80N
3
2½
65
100
125
150
150
40-60/2B
1
50-30/4FB
2
50
65
80
100
100
972/992
40-60/2B
3
50-60/FB
2
50
65
80
100
100
1142/1182
40-60/2B
3
50-60/FB
2½
65
80
100
100
100
1242/1292
40-60/2B
3
50-60/FB
2½
65
80
100
100
100
1362/1412
50-120FB
1
50-60/FB
2½
65
80
100
100
100
1662/1722
50-120FB
3
80-120FB
2½
65
80
100
125
125
1852/1922
50-120FB
3
80-120FB
2½
65
80
100
125
125
2004/2214
50-120FB
3
80-120FB
3
80
100
125
125
125
2404/2634
80-120FB
2
80-120FB
3
80
100
125
150
150
2804/3164
80-120FB
3
80-120FB
3
80
100
150
150
150
3304/3694
80-120FB
3
80-120FB
4
100
125
150
150
150
3804/4224
80-120FB
3
80-120FB
4
100
125
150
150
150
PUMP SELECTION
For the most efficient operation of the water heating system the
circulating pump must be sized correctly.
The pump should be installed on the inlet to the water heater especially
where the system water pressure is low.
Refer to the “Water Flow Rate and Pressure Drop” table on page 17 for
the minimum and maximum flow rates for each model to determine the
pressure loss through the water heater for the required temperature rise
and add this to the other system pressure losses when sizing the pump.
Note: The flow rate must never be below the minimum stated in the
“Water Flow Rate and Pressure Drop” table.
Where the water flow rate exceeds the maximum shown in the “Water
Flow Rate and Pressure Drop” table, a bypass with a balancing valve must be installed to reduce the water flow
through the water heater (refer to diagram above).
For pump sizing where the water heating system incorporates Rheem storage tanks, refer to the “Pump Selection
and Pipe Size” table on page 16.