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HRV3−095 Port Configuration & Airflow
THREADED INSERTS
(4) at corners
FILTER
(in back
chamber)
18−1/2" (470 mm)
FRESH AIR
TO INSIDE
(Supply) 6"
(178 mm)
round
(converted to
oval collar)
STALE AIR TO OUT-
SIDE (Exhaust) 5" (127
mm) round collar
STALE AIR FROM IN-
SIDE (Exhaust) 6" (178
mm) round (converted
to oval) collar supplied
FRESH AIR
FROM
OUTSIDE
(Supply) 5"
(127 mm)
round collar
ADJUSTABLE HANGING
STRAPS WITH S HOOK (4)
DRAIN
SPOUT
DRAIN
PAN
CORE
24−1/2"
(622 mm)
16"
(406 mm)
18−1/2"
(470 mm)
18 inches (457
mm) (min.) required
for service access
TOP VIEW
HRV3−095
ÎÎÎ
ÎÎÎ
ÎÎÎ
ÎÎÎ
ÏÏÏ
ÏÏÏ
ÏÏÏ
FRESH
AIR
FROM
OUT-
SIDE
FRESH
AIR TO
INSIDE
STALE
AIR TO
OUT-
SIDE
STALE AIR FROM INSIDE
DIVIDER PANEL
(each side)
FILTER
(in front
chamber)
A
B
A
B
D
D
C
A
B
D
C
C
HRV3−095 Air Flow Direction
The top half of the unit is divided front to back. This unique configuration allows the air to actually travel through the core
twice, making the HRV3−095 unit almost as efficient as a double core unit.
Stale air enters the front right side port. The air will pass down the front half of the core, then up the back half of the core
and out the right rear port.
Fresh outdoor air will enter the left rear port and pass down the back half of the core. It will then pass up the front half of the
core, and out the left front port.
Defrost Cycle (HRV)
The HRV has an electronically controlled defrost system.
The defrost cycle is activated when the outdoor tempera-
ture drops below 27ºF (−3ºC). There are three levels of de-
frost mode based on the outdoor temperature. Incoming
fresh air is measured to set the defrost times and the run
times while in the defrost mode. The three defrost settings
are:
S
At 27ºF (−3ºC) HRV runs in defrost for 3 minutes and
runs in ventilation for 25 minutes
S
At −4ºF (−20ºC) HRV runs in defrost for 4.5 minutes and
runs in ventilation for 17 minutes
S
At −31ºF (−35ºC) HRV runs in defrost for 7 minutes and
runs in ventilation for 15 minutes
No remote device can override this defrost mode or se-
lected speed until the cycle is complete. After the cycle is
completed the HRV defaults to previous settings. If the
cycle is completed and the thermistor continues to mea-
sure defrost temperature the defrost cycle is repeated.
ERV’s have no defrost cycle and are not recommended
where outdoor temperatures fall below 25ºF (−4ºC) contin-
uously for more than 5 days.
Recirculating Damper Defrost (HRV3−095,
HRV3−150−TPD, HRV4−150, HRV4−200)
During defrost a motor driven damper door mechanism
closes off the supply air from outside allowing exhaust air
to recirculate through the unit’s core. During defrost cycle
no ventilation is occurring. After the defrost period, the
damper operates in the opposite direction to reopen the
fresh air port. Defrost cycle repeats until the temperature
rises above 27ºF (−3ºC).
Damper Defrost − 5 port Models (HRV3−195/300)
During defrost a motor driven damper door mechanism
closes off the supply air from outside allowing a fifth port to
open enabling warm air to be drawn in from around the
unit. During defrost cycle stale air exhaust is still occurring.
After the defrost period, the damper operates in the oppo-
site direction to reopen the fresh air port. Defrost cycle re-
peats until the temperature rises above 27ºF (−3ºC). (The
defrost port can also be ducted to another location.)
Fan Defrost (HRV3−150−TPF)
During defrost cycle, the Fresh Air supply motor will shut
off and the Stale Air exhaust motor will continue to run.
After the defrost period, the Fresh Air supply motor will re-
sume. Defrost cycle repeats until the temperature rises
above 27ºF (−3ºC).
6" Diameter
SAME CIRCUMFERENCE
In order to make the HRV3−095 unit as space efficient as possible, the
indoor supply and return ports are converted from round to oval
shape. Circumference of the port remains the same. Simply bend a
standard duct fitting to the correct shape, and attach to the oval port
using the same method as for a round port.
Figure 1. Shaping Ducting to fit Oval Indoor
Supply Port
