System Piping - RBI IEW-199 Installation And Operation Instructions Manual

WATER PIPING AND CONTROLS
d. Table 4.4 provides the flow rate and pressure drop
information that corresponds to various system
temperature rise values (DT). The pressure drop
shown is for the boiler only. If there is significant
system pressure drop in the system, this should be
included when specifying pumps.
Table 4.4: Flow Rate and Pressure Drop for Various
System Temperature Rise Values
Temperature Rise / Pressure Drop
DT
IEW-199
(°F) (°C) GPM LPM Ft
11
20 18.2 68.9 17.12 5.22
e. Table 4.5 provides a list of recommended pumps
for hot water supply boilers.
Table 4.5: Pump Selection Chart (General Pump –
Primary/Secondary)
Pump Temperature
Manufacturer Difference
Taco
20°F
Bell & Gossett
* An isolation relay must be used for these circulators and any circulator
with a FLA rating above 4.5 Amps.
16
IEW-399
m GPM LPM Ft m
37.3 141.2 18.08 5.51
IEW-199 IEW-399
1400-20* 1400-50*
PL-36* PL-55*
D. SYSTEM PIPING
1. Figure 4.3 shows piping for a single boiler with a
single storage tank. When using the factory specified
pump, the maximum total pipe length is 30 feet (10
meters) with 6 90° elbows all at the full pipe diameter
of the pump connections.
2. In Figure 4.4, a single boiler is used with multiple
water storage tanks. The pumps are piped in parallel
with reverse return piping.
3. Figure 4.5 shows two boilers piped into a single
storage tank.
4. Figure 4.6 shows piping for two boilers and two water
storage tanks.
5. In Figure 4.7, we show a single boiler with a single
tank using a patented anti-scale principle. In this
configuration, the boiler control switches the 3-way
valve to bypass when the call for heat ends. The
pump is then operated to draw cool water from the
anti-scale buffer tank until the supply and return
temperatures equalize.