Munters DEW-150, Operating And Maintenance Manual

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5–3
temperature to drop to 120
°
F. This is the correct setting for the process damper.
7. If you close the process damper completely, or almost completely, and the reactiva-
tion outlet temperature is still low, one of the heating elements may have stopped
working. See section 5.7, Checking the Heating Elements.
8. A low outlet temperature can also be caused by a problem with the reactivation
blower. Turn off the HC-150 and try to spin the blower by hand. It should turn freely.
9. Model HC-150I only – There may be a problem with the overheat anticipator sensor
(TS03).
10. Model HC-150I only – This condition can also be caused by a faulty solid state
power control (SSP1).
11. Model HC-150R only - This condition may be caused by an open temperature
switch (TS04).
5.5 POOR DEHUMIDIFYING PERFORMANCE
1. Check the two intake filters, shown in Fig. 1–4. If these filters are dirty, clean them
as described in section 4.1, Cleaning the Air Filters.
2. If you have installed bird screens on the intake and outlet for the reactivation air,
check these.
3. Has something changed in the process space which could increase the moisture
load on the unit? Check all openings into the process space to be sure all doors
and windows are closed. Check for leaks in the ductwork.
4. The volume of process air may be too great. You can reduce the volume of process
air by closing the process damper.
5. Check the air temperature at the outlet for the reactivation air. It should be 120
°
F,
±
5
°
. If it is not, see section 5.4, Reactivation Outlet Temperature is Too Low.
6. One or more of the heating elements may not be working. See section 5.7, Check-
ing the Heating Elements.
7. If the process blower is overloaded, it will shut down automatically. This will prevent
the unit from drying the process air. The motor will restart automatically, once it has
cooled.
8. The HoneyCombe
®
wheel may be stopped. See the next section.
9. Model HC-150I only – There may be a problem with the overheat anticipator sensor
(TS03).
5.6 HONEYCOMBE
®
WHEEL IS STOPPED, RUNNING LIGHT IS ON
1. Check the drive system. See Fig. 1–4. Pull back on the tensioner to loosen the
belt. Remove the belt from the drive wheel on the motor. Set the Manual/Off/Auto
switch to the Manual position to turn on the unit. The drive motor should turn slowly.
See section 5.10, Checking the Drive Motor, Wheel and Seals.