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13
Override Test
To use override test function, a thermistor must be connected to the
control board. Unit must not be in defrost mode during an override
test.
HIGH SPEED
1. Disconnect HRV from 115VAC.
1. Unplug wall control wires at control module terminal block
inside HRV.
2. Plug HRV back to 115VAC.
3. Attach a wire across J3--8 and J3--9 (B and G) on control
module terminal block.
4. Push in door switch, this will initiate a high--speed ex-
change.
LOW SPEED
1. Unplug HRV from 115VAC.
2. Disconnect wall control wires at control module terminal
block inside HRV.
3. Plug HRV back to 115VAC.
4. Connect a 3.0 K ohm resistor between J3--8 and J3--9 (B
and G) on control module terminal block.
5. Push in door switch, this will initiate a low--speed exchange.
Blower Speed Selection
Three--speed blowers are factory connected to electronic control
board on HIGH-- and LOW--speed taps of blowers. Installer can
easily change low--speed tap to medium--speed tap so electronic
control will select between high and medium speed. Connections
can be changed at motor location (see Table 8 and Table 9).
To change low speed to medium speed, proceed as follows:
1. Unplug unit from 115VAC.
2. Locate blower assembly.
3. Locate red wire and blue wire coming from blower as-
sembly.
4. Unplug red wire from quick connect.
5. Unplug protecting cap quick connection from blue wire and
put on red wire coming from blower. The cap is a safety
insulator.
6. Connect red wire of main harness to blue wire.
7. Replace wires.
Table 8 – Factory Set Blower Connection High or Low Speed
CONTROL
MODULE
MAIN
ELECTRICAL
HARNESS
CABLE
BLOWER
WIRE
SPEED
J1---6
Orange
Orange
High
No Connection
No Connection
Blue + Cap
Medium
J1---4
Red
Red
Low
Table 9 – Modify Blower Connection High or Medium Speed
CONTROL
MODULE
MAIN
ELECTRICAL
HARNESS
CABLE
BLOWER
WIRE
SPEED
J1---6
Orange
Orange
High
J1---4
Red
Blue
Medium
No Connection
No Connection
Red + Cap
Low
Table 10 – Temperature and Voltage
VOLTAGE DC VOLTS (J4)
TEMP
°
F (
°
C)
3.5
---22 (---30)
2.7
---4 (---20)
2.3
4 (---15)
2.0
14 (---10)
1.4
32 (0)
1.1
41 (5)
0.9
50 (10)
0.6
68 (20)
Defrost Cycle
Defrost cycle is controlled by a thermistor which is located in the
fresh--air intake passage (the thermistor unit is connected to J4 of
control module (see Fig. 14). When defrost temperature sensor
detects the need for defrost, K5 relay will close for 6 minutes while
K1 and K2 remain energized.
This closes the outdoor air damper while running HRV blower on
high--speed. This process recirculates warm indoor air through heat
recovery core which melts any frost that has formed. Water created
in this process is collected by HRV and drained away. Frequency
of the defrost cycle depends on outdoor temperature (see Table 11).
Table 11 – Defrost Cycle
OUTSIDE TEMPERATURE
STANDARD DEFROST (AS SHIPPED)
EXTENDED DEFROST
(JUMPER JU1---F REMOVED)
Above 23
°
F/---5
°
C
No Defrost
No Defrost
23
°
F to 5
°
F/---5
°
C to ---15
°
C
6 Minute Defrost/32 Minute Exchange
10 Minute Defrost/30 Minute Exchange
4
°
F to ---17
°
F/---16
°
C to ---27
°
C
6 Minute Defrost/32 Minute Exchange
10 Minute Defrost/20 Minute Exchange
Below ---18
°
F/---28
°
C
6 Minute Defrost/20 Minute Exchange
10 Minute Defrost/15 Minute Exchange
Table 12 – JU1 Jumper Definition
JU1A
JU1B
JU1C
JU1D
JU1E
JU1F
JU1G
UNIT IDENTIFICATION
Reverse Damper Operation
In=Normal
OUt=Inverse
Factory Set
Always In
Factory Set
Always In
Table 13 – Jumper Locations
MODEL
JUMPER TABLE
JU1A
JU1B
JU1C
JU1D
JU1E
JU1F
JU1G
HRVXXLVU1330
OUT
OUT
OUT
OUT
IN
IN
IN