User Guide

40
Design Guide - HZH/HZV Series
EWT
ºF
GPM
WPD Cooling - EAT 80/67ºF Heating - EAT 70ºF
PSI FT
Airow
CFM
TC SC
Sens/
Total
Ratio
kW HR EER
Airow
CFM
HC kW HE LAT COP
70
4.5 1.1 2.5 1080 37.8 25.7 0.68 2.22 45.3 17.0 1080 44.0 2.71 34.8 107.7 4.75
4.5 1.1 2.5 1250 38.7 28.2 0.73 2.32 46.6 16.7 1250 44.8 2.60 36.0 103.2 5.05
6.8 2.9 6.7 1080 39.1 26.2 0.67 2.08 46.1 18.8 1080 46.4 2.79 36.9 109.8 4.88
6.8 2.9 6.7 1250 40.0 28.8 0.72 2.17 47.4 18.4 1250 47.3 2.67 38.2 105.0 5.19
80
4.5 1.0 2.3 1080 35.8 24.8 0.69 2.44 44.2 14.7 1080 48.3 2.84 38.6 111.4 4.98
4.5 1.0 2.3 1250 36.7 27.2 0.74 2.55 45.4 14.4 1250 49.2 2.73 39.9 106.5 5.29
6.8 2.8 6.6 1080 37.2 25.4 0.68 2.29 45.0 16.3 1080 51.1 2.93 41.1 113.8 5.10
6.8 2.8 6.6 1250 38.0 27.9 0.73 2.39 46.2 15.9 1250 52.1 2.81 42.5 108.6 5.43
85
4.5 1.0 2.2 1080 34.8 24.3 0.70 2.57 43.6 13.6 1080 50.5 2.92 40.6 113.3 5.08
4.5 1.0 2.2 1250 35.6 26.7 0.75 2.68 44.8 13.3 1250 51.5 2.80 41.9 108.1 5.40
6.8 2.8 6.4 1080 36.2 25.0 0.69 2.40 44.4 15.0 1080 53.5 3.02 43.2 115.9 5.20
6.8 2.8 6.4 1250 37.0 27.4 0.74 2.51 45.6 14.7 1250 54.5 2.89 44.7 110.4 5.53
90
4.5 0.9 2.1 1080 33.8 23.9 0.71 2.70 43.0 12.5 1080 52.7 2.99 42.5 115.2 5.17
4.5 0.9 2.1 1250 34.6 26.2 0.76 2.81 44.2 12.3 1250 53.7 2.86 44.0 109.8 5.50
6.8 2.7 6.2 1080 35.1 24.5 0.70 2.52 43.8 13.9 1080 55.9 3.10 45.3 117.9 5.29
6.8 2.7 6.2 1250 36.0 26.9 0.75 2.63 45.0 13.7 1250 57.0 2.97 46.9 112.2 5.62
With the ClimaDry
®
II, return air from the space is cooled by
the air-to-refrigerant (evaporator) coil, and then reheated
by the water-to-air (reheat) coil to dehumidify the air, but
maintain the same space temperature (thus operating as a
dehumidier).
The moisture removal capability of the heat pump is
determined by the unit’s latent capacity rating. Latent
capacity equals Total capacity minus Sensible capacity.
Using unit performance data from submittals select
the correct model, use your maximum entering water
temperature (EWT) and ow rate to select TC and SC. For
example, at 80°F [26.7°C] EWT and 6.8 GPM, the moisture
removal capability (latent capacity) of a Comfort-Aire/
Century unit is 11.8 Mbtuh [3.5kW] as shown below.
Dividing the latent capacity by 1,069 BTU/LB of water vapor
at 80°F DB and 67°F WB [26.7°C DB and 19.4°C WB] moist
air enthalpy, converts the amount of moisture removal to
pounds per hour (multiply pounds per hour by 0.4536 to
obtain kg/hr). Calculations are shown below.
Most Comfort-Aire/Century heat pumps have a
sensible-to-total (S/T) ratio of 0.72 to 0.82. Therefore,
approximately, 25% of the cooling capacity is dedicated
to latent cooling capacity (moisture removal). When
selecting a unit with ClimaDry
®
II, the space sensible and
latent loads should be calculated. If the unit will be used
for space cooling, a unit with at least enough capacity to
satisfy the building sensible load should be selected. If
the latent cooling load is not satised by the selection, a
larger unit with enough latent capacity will be required. If
the unit will be used for dehumidication purposes only,
the latent capacity is the only consideration necessary. In
this case, sensible load is immaterial.
ClimaDry
®
II - Benets and Application
Example Performance
Dividing the latent
capacity by 1,069 BTU/
LB of water vapor at
80°F DB and 67°F
WB [26.7°C DB and
19.4°C WB] moist air
enthalpy, converts the
amount of moisture
removal to pounds per
hour (multiply pounds
per hour by 0.4536 to
obtain kg/hr).
LC = TC - SC = 37.2 - 25.4 = 11.8 Mbtuh
11,800 Btuh ÷ 1069 = 11.0 lbs/hr