Aprilaire 1700 - Manual (Page 15)

15
TROUBLESHOOTING GUIDE
(CONTINUED)
SYMPTOM TROUBLESHOOTING PROCEDURE / POSSIBLE REASON
The ventilation damper
does not open when the
HVAC fan is active. • The damper will not open if the cycle time within the current period has already
been met. For instance if the cycle time is set to 5 minutes and the control has
already ventilated for 5 minutes in that interval, the damper will remain closed.
• If using the Outdoor Temperature Sensor, check
that it is installed in the Outdoor Air Intake a
maximum of 3 feet from the outside, or on the
North, East or West side of the house.
(Not in direct sunlight.)
• If the outdoor temperature is below 0°F or above
100°F, the damper will remain closed.
• Verify that the Outdoor Temperature Sensor
is reporting an accurate resistance. Remove the
Outdoor Temperature Sensor leads from ODT
Sensor terminals and check the resistance.
Compare the reading with the resistance shown
in Table 2.
The fan turns on unexpectedly. • The control will turn on the fan as needed to meet the air cycling requirements
determined by the cycle time and cycle period settings.
The dehumidifier does not run. • Follow all of the system checkout procedures.
• Check that the power switch on the dehumidifier is on.
• Check that the circuit breaker is not tripped. The dehumidifier requires a
minimum of 8 amps. The dehumidifier should be placed on its own dedicated
15 amp circuit.
The compressor never runs. • If a float switch is not installed, confirm that the jumper is installed at the
float switch terminals on the control board.
• If a float switch is installed, confirm that the float switch is not open.
Outdoor
Temperature
-30˚F
-20˚F
-10˚F
0˚F
10˚F
20˚F
30˚F
40˚F
50˚F
60˚F
70˚F
80˚F
90˚F
100˚F
Resistance
229,500 OHMS
162,500 OHMS
116,500 OHMS
84,500 OHMS
62,000 OHMS
46,000 OHMS
34,500 OHMS
26,000 OHMS
20,000 OHMS
15,500 OHMS
12,000 OHMS
9,500 OHMS
7,500 OHMS
6,000 OHMS
TABLE 2