American Aldes Heat Recovery Ventilator HRV 120SRD, Operation And Installation Manual

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AIR FLOW MEASURING KIT
The American ALDES air
fl
ow measuring kit is designed to measure
air
fl
ow accurately in ducting. Utilizing the Ampli
fl
ow sensor by Nailor-
Hart Industries, it is three times as sensitive as a Pitot tube, allowing
the measurement of very low velocities. The design also averages the
variations in velocity pressure across the diameter of the duct, to provide
a mean air
fl
ow reading.
The Air
fl
ow Measuring
Kit is comprised of the
following items:
Ampli
fl
ow sensors for 6”
•
and 8” ducting.
Dwyer Magnehelic
•
pressure gauge, 0-0.25 in.
w.g. range.
Flexible tubing to connect
•
pressure gauge to sensors
Air
fl
ow Table to convert
•
pressure readings to
air
fl
ow in cfm.
FEATURES:
Ampli
fl
ow
®
sensor*:
Multi-point readings eliminate need for pitot tube traverses.
•
Adaptable to round, oval or rectangular duct.
•
Accurate low velocity readings—provides 3 times the pressure reading
•
of a Pitot tube at the same velocity.
Dwyer Magnehelic
®
—an industry standard in differential pressure
measurement.
Accuracy of measurement: Plus or minus 4% of full scale at 70 F.
•
Can accept overpressure up to 15 PSI.
•
Comes with mounting stand, 1/8 tubing connectors, probe for static
•
pressure measurements, plastic storage case.
Dual scale readings for pressure (in. w.g.) and velocity (FPM) when
•
used with a Pitot tube.
BALANCING PROCEDURE
Prior to balancing, make sure that:
All sealing of the ductwork system
•
has been completed.
All of the HRV’s components are in
•
place and functioning properly.
Balancing dampers are fully open.
•
Adjustment of air
fl
ows at the
•
individual grilles should be done
prior to balancing the total supply
and exhaust air
fl
ows. A smoke
pencil maybe used to indicate
relative air
fl
ows at the supply or
exhaust grilles.
Set the pressure gauge on a level
1.
surface, near the duct location where
the air
fl
ow is to be measured. Check
to see it reads zero, with no air
fl
ow
across the sensor. If not, use a small
screwdriver to adjust the meter. See
the Dwyer instructions packaged
with the Magnehelic gauge.
Insert the Ampli
fl
ow sensor into 2.
a straight section of duct, with the
arrow pointing in the direction
of the air
fl
ow. To avoid air
fl
ow
turbulence and incorrect readings,
the
fl
ow sensor should be located
at least three (3) diameters
downstream from elbow, balancing damper, etc. If
fl
exible ducting
is used, it may be advisable to insert the Ampli
fl
ow sensor into a
short collar of metal duct.
Be sure to connect the low and high pressure taps on the gauge to the
3.
corresponding taps on the Ampli
fl
ow sensors.
Turn the unit to HIGH speed. (Note: it may be necessary to reduce 4.
the speed if the pressure gauge is driven off scale. No damage
will result, the gauge is capable of 15 PSI, much higher than the
maximum scale reading.)
Find the air
fl
ow from the column matching the duct diameter and the 5.
pressure reading on the upper scale of the gauge.
After taking readings of both the stale air to the HRV/ERV duct and
6.
the fresh air to the house duct, the duct with the lower cfm should
be left alone, while the duct with the higher reading should be
dampered back to match the lower reading.
Remove the
fl
ow sensor from the duct and seal the holes with 7.
approved duct tape. The sensor may be left in place to check air
fl
ows
later.
Return the unit to appropriate fan speed for normal operation. Note:
8.
Air
fl
ows may be measured in smaller diameter ducts by taping over
the sensor holes on the tubing that are exposed outside the duct.
Failure to close them will result in low readings.
*Ampli ow
®
is a Registered Trademark of Nailor-Hart Industries.
Magnehelic
®
is a Registered Trademark of Dwyer Instruments,
Inc.
Place sensing probe a minimum of 3
diameters downstream from blower, elbows,
or dampers.
NOTE: Duct connections may vary,
depending on model.
AIRFLOW TABLE FOR AMPLIFLOW SENSOR
Delta
P In.
W.G.
Velocity
FPM
CFM 4”
Diam.
CFM 5”
Diam.
CFM 6”
Diam.
CFM 7”
Diam.
0.005 150 13 20 29 40
0.010 212 19 29 42 57
0.015 260 23 35 51 69
0.020 300 26 41 59 80
0.025 335 29 46 66 90
0.030 367 32 50 72 98
0.035 397 35 54 78 106
0.040 424 37 58 83 113
0.045 450 39 61 88 120
0.050 474 41 65 93 127
0.055 497 43 68 98 133
0.060 520 45 71 102 139
0.065 541 47 74 106 145
0.070 561 49 77 110 150
0.075 581 51 79 114 155
0.080 600 52 82 118 160
0.085 618 54 84 121 165
0.090 636 56 87 125 170
0.095 654 57 89 128 175
0.100 671 59 91 132 179
0.105 687 60 94 135 184
0.110 704 61 96 138 188
0.115 719 63 98 141 192
0.120 735 64 100 144 196
0.125 750 65 102 147 200
0.130 765 67 104 150 204
Delta
P In.
W.G.
Velocity
FPM
CFM 4”
Diam.
CFM 5”
Diam.
CFM 6”
Diam.
CFM 7”
Diam.
0.135 779 68 106 153 208
0.140 794 69 108 156 212
0.145 808 70 110 159 216
0.150 822 72 112 161 220
0.155 835 73 114 164 223
0.160 849 74 116 167 227
0.165 862 75 117 169 230
0.170 875 76 119 172 234
0.175 887 77 121 174 237
0.180 900 79 123 177 241
0.185 912 80 124 179 244
0.190 925 81 126 182 247
0.195 937 82 128 184 250
0.200 949 83 129 186 254
0.205 960 84 131 189 257
0.210 972 85 133 191 260
0.215 984 86 134 193 263
0.220 995 87 136 195 266
0.225 1006 88 137 198 269
0.230 1017 89 139 200 272
0.235 1028 90 140 202 275
0.240 1039 91 142 204 278
0.245 1050 92 143 206 281
0.250 1061 93 145 208 283
Ampli
fl
ow
Sensor
Ampli
fl
ow
Sensor
28