8
COOLING LOAD BTU
Outside
Cooling Load (BTUh) @ Inside Design
Temp 75
°
F and 50% Relative Humidity
Outside
Enthalpy
Btu/lb
HRVCCLHA1150
HRVCCLHA1250
30
670
1,071
31
1,090
1,741
32
1,509
2,411
33
1,928
3,080
34
2,347
3,750
35
2,766
4,419
36
3,185
5,089
37
3,604
5,759
38
4,023
6,428
39
4,442
7,098
40
4,861
7,767
41
5,280
8,437
42
5,699
9,107
The cooling load chart shows the loads in BTUh also. To use the
cooling load chart, first find the design enthalpy from a
psychrometric chart using the design dry bulb and wet bulb
temperatures. (See following psychrometric chart.) The cooling
load can then be found for a range of enthalpies for each
ventilator.
EXAMPLE:
The cooling design dry bulb temperature for
Milwaukee, WI, is 87
_
F and the average wet bulb at that
temperature is 73
_
F. On the psychrometric chart the enthalpy is
about 37.7 BTU/lb of dry air which will round up to 38 BTU/lb
of dry air. In the left column, at 38 BTU/lb the HRVCCLHA1250
would have an additional cooling load of 6428 BTUh. This
additional load should be taken into account when sizing the air
cooling equipment.
HR
V
