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HWM-407CH-IOM (09/13)
Page 24
7. Heat Exchanger Maintenance
A compact brazed heat exchanger is utilized in the Hydronic Water Module.
The water flow rate designed into each of these heat exchangers is 2 or more gallons per
minute per ton of nominal system capacity.
The acceptable water flow rate range for each system is shown in Figure 12. While it is
important for the proper performance of the heat exchanger to maintain water flow rate
between the minimum and maximum shown,
it is CRITICAL that the flow rate
not drop
below the minimum.
COMPRESSOR UNIT SIZE
& CAPACITY, BTUH
HWM
MODELS
MIN. WATER
FLOW RATE,
GPM
-018 (18,000)
-18B
3.0
-024 (24,000)
-24B
4.0
-030 (30,000)
-30B
5.0
-036 (36,000)
-36B
6.0
-042 (42,000)
-42B
7.0
-048 (48,000)
-48B
8.0
-060 (60,000)
-60B
10.0
-072 (72,000)
-72B
12.0
Figure 12. Minimum Heat Exchanger Water Flow Rates
Figure 13 shows minimum antifreeze solution flow rates for various mixtures of propylene
glycol and water
.