13
Dirty filters are the most common cause of inadequate
heating or cooling performance. Filter inspection should be
made at least every two months; more often if necessary
because of local conditions and usage.
Dirty throwaway filters should be discarded and replaced
with a new, clean filter.
Disposable return air filters are supplied with this unit. See
the unit Specification Sheet or Technical Manual for the
correct size and part number. To remove the filters, remove
the filter access panel on return side of the unit.
Clean Outside Coil (Qualified Servicer Only)
The coil with the outside air flowing over it should be
inspected annually and cleaned as frequently as necessary
to keep the finned areas free of lint, hair and debris.
Lubrication
The supply fan motors, the condenser fan motors and
compressors are permanently lubricated.
Functional Parts
Refer to the unit Parts Catalog for a list of functional parts.
Parts are available from your distributor.
Cabinet Finish Maintenance
Use a fine grade automotive wax on the cabinet finish to
maintain the finish’s original high luster. This is especially
important in installations with extended periods of direct
sunlight.
Maintenance of MicroChannel
Heat Exchangers (MCHE)
Frequent servicing is essential to maintaining the required
MCHE performance. For every installed Danfoss MCHE,
service records must be documented.
CAUTION
Prior to servicing MCHE, be sure to disconnect the power
supply and use lock-out methods to prevent the power from
accidentally being turned on.
Shut Down Periods
During periods when the MCHE is not operated for longer
than a week, the MCHE must be completely cleaned
following the cleaning procedure. This practice must
also be performed during short shut-down periods where
corrosive deposits accumulate on the MCHE.
Cleaning Procedure
Relative to tube & fin heat exchangers, MicroChannel
heat exchanger coils tend to accumulate more dirt on the
surface of the coil and less dirt inside the coil, making them
easier to clean. Follow the steps below for proper cleaning:
STEP 1: Remove Surface Debris
Remove surface dirt, leaves, fibers, etc. with a vacuum
cleaner (preferably with a brush or other soft attachment
rather than a metal tube), compressed air blown from the
inside out, and/or a soft bristle (not wire!) brush. Do not
impact or scrape the coil with the vacuum tube, air nozzle,
etc.
STEP 2: Rinse
Rinse the coil by following procedure:
1. Rinse the coil by approved MCHE cleaner first, or
rinsing by water directly;
2. Waiting for 5 minutes;
3. Wash the coil by water;
Adjust the angle of gimbaled nozzle and insert it
through fans. Using an extension rod if the nozzle
cannot reach the bottom side. Preferably cleaning
the coils from the inside-out and top to bottom
(see figure 1), running the water through every
fin passage until it comes out clean. The fins of
MicroChannel coils are stronger than traditional tube
& fin coil fins but still need t
o be handled with care.
Do not hit the coil with the hose. We recommend
placing your thumb over the end of the hose to
obtain a gentler spray and reduce the possibility of
impact damage. Please PAY MORE ATTENTION
when using a pressure cleaning equipment to
prevent damage.
Figure 1
Highest pressure of cleaning equipment shall not exceed
15 bar, and tentatively move the cleaning equipment from
far to near to prevent damage.
•
KEEP the outlet of washer away from coil for at least
4in (see figure 2);
•
KEEP the water gun perpendicular to the coil
surface and the angle error shall less than 20°, or
±40° if the distance from washer to coil is more than
12in (see figure 2);
•
Water outlet angle for high pressure cleaning
equipment shall over 15° (see figure 3).
