Navien NHB H Series, Инструкция по установке и эксплуатации

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22 Installing the System Piping
Pump Sizing for Use with Glycol
The use of glycol results in a greater head loss due to its higher viscosity compared to water. Heat transfer is
also reduced as the glycol concentration increases. The corrected flow rate and head loss values below must be
used when sizing the boiler pump in order to maintain similar performance as using 100% water for the heating
system. Refer to the chart below.
Model
20°F ΔT @ 30% Glycol 25°F ΔT @ 30% Glycol 35°F ΔT @ 30% Glycol
Flow Rate
(GPM)
Head
(Ft)
Flow Rate
(GPM)
Head
(Ft)
Flow Rate
(GPM)
Head
(Ft)
NHB-055H 5.4 10.0 4.3 6.5 3.1 3.5
NHB-080H 7.8 20.2 6.3 13.4 4.5 7.0
NHB-110H 10.8 15.2 8.6 9.6 6.1 4.8
NHB-150H 14.5 27.4 11.6 17.5 8.3 9.0
Note Do not exceed a maximum concentration of 35% glycol.
Minimum Flow Rates through the Boiler for Use with Glycol
Model
Minimum Flow (GPM)
For use With 30% Glycol
NHB-055H 2.3
NHB-080H 3.4
NHB-110H 4.6
NHB-150H 6.2
Note
If the flow rate is below the required value for the specific boiler model as shown on the chart, it may
result in noise and/or potential damage to the boiler.