PeerlessBoilers PF-110, Инструкция по установке, эксплуатации и обслуживанию

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f. Table 4.5 provides the flow rate and pressure drop
information that corresponds to various system
temperature rise values (
D
T). 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 circulators.
g. Table 4.6 provides a list of recommended
circulators for boilers on a secondary loop of a
primary/secondary system which uses water as a
heating medium.
h. Special consideration must be given if a glycol
based anti-freeze solution is used as a heating
medium. Propylene glycol has a higher viscosity
than water, therefore the system pressure drop will
be higher.
10. Indirect Water Heater: An indirect water heater should
be piped to a dedicated zone. The P
URE
F
IRE
boiler
provides electrical terminals for connecting a domestic
hot water (DHW) circulator. Examples of piping for
the indirect water heater are shown under subsection
“E”, System Piping of this section.
D. SYSTEM PIPING
1. Figure 4.4 shows a single boiler with multiple heating
zones. In this case, the DHW zone is piped in parallel
to the heating zones on the primary loop.
2. For a single boiler with one heating zone and one
DHW zone which utilizes an indirect water heater like
the Peerless Partner, pipe the boiler as shown in
Figure 4.5. In systems like this, the DHW circulator
must be sized to provide the minimum flow rate
through the boiler.
3. In Figure 4.6 an additional boiler is added and more
heating zones are shown. Notice that the two boilers
are piped in parallel on the secondary loop. This
maximizes the efficiency of the boilers since the lowest
temperature system water is returning to both boilers.
4. Figure 4.7 shows a multiple boiler system with several
different types of heat distribution units. This system
illustrates how different temperature zones can be
supplied from the same source by blending supply
and return water to the zone.
5. In Figure 4.8 zone valves are used instead of zone
circulators. Notice that the system is piped using
reverse return piping to help balance the flow through
the zones. If the zone lengths vary balancing valves
are required on each loop.
E. FREEZE PROTECTION
1. Glycol for hydronic applications is specially
formulated for heating systems. It includes inhibitors
which prevent the glycol from attacking metallic
system components. Make sure that the system fluid is
checked for correct glycol concentration and inhibitor
level.
2. Use only inhibited polypropylene glycol solutions of
up to 50% by volume. Ethylene glycol is toxic and
can chemically attack gaskets and seals used in
hydronic system.
3. The anti-freeze solution should be tested at least once
per year and as recommended by the manufacturer of
the product.
4. Anti-freeze solutions expand more than water. For
example, a 50% by volume solution expands 4.8%
with a 148°F temperature rise while water expands
about 3% for the same temperature increase.
Allowance for this expansion must be considered in
sizing expansion tanks and related components.
5. The flow rate in systems utilizing glycol solutions
should be higher than in a water system to
compensate for decreased heating capacity of the fluid.
13
WATER PIPING AND CONTROLS
Table 4.5: Boiler Pressure Drop and Flow Rates for
Various System Temperature Rise Values
D
T
(°F)
Flow Rate & Pressure Drop
PF-50 PF-80 PF-110 PF-140
GPM FT GPM FT GPM FT GPM FT
40 n/a 3.20 3.2 4.40 3.1 5.65 2.3
35 2.28 2.3 3.65 4.0 5.02 3.8 6.45 2.9
30 2.66 2.9 4.26 5.1 5.86 5.0 7.53 3.7
25 3.20 3.7 5.12 7.0 7.03 6.8 9.03 5.2
20 4.00 5.4 6.39 10.4 8.79 10.0 11.29 8.0
15 5.33 8.8 8.53 17.5 11.72 17.0 15.05 14.0
10 7.99 18.5 n/a n/a n/a
The circulator sizing given is for primary/secondary
installations only. The system circulators must be
sized based on the flow and pressure drop
requirements of the system.
NOTICE
Table 4.6: Circulator Selection Chart
Circulator selections are based on boiler net output which
includes a 1.15 pick-up factor for piping losses.
Pump
Manufacturer
Temp
Difference PF-50 PF-80 PF-110 PF-140
Taco
10
0014 N/A N/A N/A
Grundfos UPS 26-99 N/A N/A N/A
Taco
15
007 0014 0014 0014
Grundfos UPS 15-58 UPS 26-99 UPS 26-99 UPS 26-99
Taco
20
006 008 008 007
Grundfos UPS 15-58 UPS 15-58 UPS 26-99 UPS 26-99
Taco
25
003 007 007 007
Grundfos UPS 15-58 UPS 15-58 UPS 15-58 UPS 15-58
Taco
30
003 006 007 007
Grundfos UPS 15-58 UPS 15-58 UPS 15-58 UPS 15-58
Taco
35
003 006 006 006
Grundfos UPS 15-58 UPS 15-58 UPS 15-58 UPS 15-58
Taco
40
N/A 003 006 006
Grundfos N/A UPS 15-58 UPS 15-58 UPS 15-58