Airtek 4087 Walden Avenue, Lancaster, NY 14086 TEL: (716) 685-4040 FAX: (716) 685-1010 E-MAIL: airtek@airtek.com WEB SITE: www.airtek.com
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Caution: The following procedures are developed for the
qualified Electrician or Refrigeration Technician. Only qualified
personnel should attempt these procedures.
Caution: When checking or repairing any unit, exercise all
safety and caution rules. Disconnect power and depressurize
unit when necessary.
*
Pressures referenced in this section refer to units using
R-22. For other refrigerants, please refer to service tag
for specifications.
Refrigerated Dryer Diagnostic Code
Diagnostic code “E1”
Shutdown on Open Dew Point Circuit
The dew point sensing circuit is devised of three parts.
The dew point probe, cable and digital control board. The
combination of these parts measures the air temperature
leaving the evaporator.
There are two connections in the dew point sensing
circuit, one between the probe (inserted in the right side of the
evaporator) and cable, and one between the cable and the
control board. If either of these two connections is broken a
diagnostic code of “E1” will appear on the control board
display, after 1 0 seconds the dryer will shut down. The dryer
will not be able to be restarted until the problem is corrected.
The easiest way to correct this is to check all connections
to make sure they are secure. If they are and you are still
experiencing the problem, there is a possibility there is an
internal break in the sensing circuit without the circuit shorting
out.
To locate the break, here is the sequence of steps to be taken:
1) Locate the connection between the probe and the cable
and disconnect it. Make sure it is secured above the
compression fitting. The connection hanging low could
attract condensation from the probe compression fitting.
This water could get into the connection causing an open
circuit.
2) Looking at the female end of the cable connection note
the five terminal points arranged in a clock like fashion, 9,
11, 12, 1 and 3 o’clock.
3) Taking a piece of insulated wire stripped on both ends,
place the ends into the 9 and 3 o’clock positions. If the
digital display then changes to “E2” the break is in the
probe.
4) If the display remains at “E1” disconnect power from the
unit and disconnect the cable (probe 1) from the main
dew point control board.
5) Looking at the male connection (labeled as Probe 1)
terminals on the control board, number them 1, 2, 3,
respectively from left to right facing the back of the board
with the board in an upright position the way it is mounted
in the dryer.
6) Take a jumper wire and attach the ends to terminal 1 and
2. Reapply power. If the display changes to “E2” the break
is in the cable. Replace the cable. If the display remains
“E1” the break is in the board. Replace the board.
Diagnostic code “E2”
Shutdown on Shorted Dew Point Circuit
The dew point sensing circuit is devised of three
parts, The dew point probe, cable and digital control board.
The combination of these parts measures the air tempera-
ture leaving the evaporator.
If a short should occur somewhere in the dew
point sensing circuit, a diagnostic code of “E2” will appear
on the control board. After 1 a seconds of this condition the
dryer will shut down. The dryer will not be able to be
restarted until the problem is corrected.
To determine which component is at fault, first find
the two connections in the sensing circuit, one between the
dew point probe and cable, and one between the cable and
the digital control board.
Then follow these simple steps.
1) Locate the connection between the probe and cable
and disconnect it. Make sure it is secured above the
compression fitting. The connection hanging low could
attract condensation from the probe compression
fitting. This water could get into the connection causing
an open circuit.
2) Should the display on the digital control board change
from a “E2” to a “E1”, the short is in the dew point
probe. Replace it.
3) If the display continues to show a “E2” disconnect
power to the unit and locate the connection between
the cable and the digital control board, and disconnect
it.
4) Reapply power. If the display then changes to an “E1”
the short is in the cable. Replace the cable.
5) If the display still shows a “E2” the short is in the
suction line temperature probe (E3 Probe) or the digital
control board. The process to determine to disconnect
power connection labeled “Probe 2”
1) Disconnect the cable. Reapply power. If the
display changes from “E2” to a number, the
short is in the suction temperature probe.
Replace the probe. If the “E2” remains the
short is in the control board. Replace the
control board.
Diagnostic code “E3”
Shutdown on High Super Heat
Super heat is defined by the differential temperature
between the thermal expansion valve bulb and the actual
dew point. The standard superheat setting fluctuates
between 10ºF. and 25ºF.
If the temperature at the thermal expansion valve
sensing probe is 40ºF higher than the actual dew point
readout for 40 minutes, the display will read “E3” and
automatically shut down. This shutdown eliminates a
compressor seizure. The dryer can be reset by pressing
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