Alancing The Nit; What You Need To Balance The Unit; Hat You Eed To Alance The Nit; Preliminary Stages To Balance The Unit - Broan ERV70S Guia De Instalacion

8. B U
ALANCING THE NIT
8.1 W N
HAT YOU EED TO
• A magnehelic gauge capable of measuring 0 to 0.5 inch of water (0 to 125 Pa) and
2 plastic tubes.
• The balancing chart of the unit, located on the unit door.
8.2 P S
RELIMINARY TAGES TO
• Seal all the unit ductwork with tape. Close all windows and doors.
• Turn off all exhaust devices such as range hood, dryer and bathroom fans.
• Make sure the balancing dampers are fully open (their adjusment pin (A) must be set
vertical, see illustration at right).
• Make sure all filters are clean (if it is not the first time the unit is balanced).
8.3 B P
ALANCING ROCEDURE
1. Set the unit to high speed.
NOTE: Make sure that the furnace/air handler blower is ON if the installation is in any way connected to the ductwork of the
cold air return. If not, leave furnace/air handler blower OFF. If the outdoor temperature is below 32°F, make sure the unit
is not running in defrost while balancing. (By waiting 10 minutes after plugging the unit in, you are assured that the unit
is not in a defrost cycle.)
2. Place the magnehelic gauge on a level surface and adjust it to zero.
3. Connect tubing from gauge to EXHAUST air flow pressure taps (see diagram on unit
door).
Be sure to connect the tubes to their appropriate high/low fittings. If the gauge drops
below zero, reverse the tubing connections.
4. Note the CFM value from balancing chart on unit.
5. Repeat steps 3 and 4, but to FRESH air flow pressure taps.
6. Match highest CFM value to lowest by adjusting the balancing damper corresponding
to the highest value. To do so, rotate the adjusment pin.
See example below:
P
RESSURE
. . .
IN W G
0.16
0.18
0.2
0.22
0.24
0.26
0.28
0.3
In that case, there is 78 CFM in FRESH air and 61 CFM in EXHAUST air. Then, using the adjusment pin, adjust (close) the
FRESH air balancing damper until the FRESH air flow matchs the EXHAUST air flow: 60 CFM (0.2 in. w.g.) with magnehelic
gauge connected to FRESH air flow pressure taps).
7. Secure both dampers in place with a fastening screw (included in the hardware kit).
8. Write the required air flow information on a label and stick it near the unit for future
reference (date, maximum speed air flows, your name, phone number and business
address).
NOTES: 1. Use conversion chart provided with the unit to convert magnehelic gauge
readings to equivalent cfm values.
2. The unit is considered balanced even if there is a difference of ±10 cfm
(or ± 5 l/s or 17 m³/h) between the two air flows.
B U
ALANCE THE NIT
B U
ALANCE THE NIT
F
RESH
CFM
47
54
60
66
72
78
84
90
E
XHAUST
CFM
42
48 E
XHAUST
READING
55
VALUES
61
68
74
F
RESH
81
READING
88
VALUES
17
VP0009
VJ0033
VP0019
E
VJ0031
VJ0031
A
F A
RESH IR
F
LOW
A F
XHAUST IR LOW
S
CREW