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To adjust the defrost timer:
1. Unplug the unit.
2. Remove the top panel and the front cover (6 screws).
3. The timer is fastened to the base at the front of the
unit. Every third peg around the dial is pushed out
from the dial center except one section with 4 pegs
out in a row. The grain control (8 holes at the intake
of the unit below the filter) should be open. Refer to
Figures 3 and 4.
4. To improve performance below 50°F, the compressor
“off” time must be increased to allow the frost to
completely melt. To do this, push the pegs out from
the dial center so that the pegs alternate with 2
toward the center, then 2 out from the center, all the
way around the dial except for the section now with 6
pegs out in a row. Refer to Figure 4.
5. Replace the cover and top panel.
2.10 Low Pressure Control
If the low side refrigerant pressure drops to 15 PSIG, the
low pressure control opens and shuts off the compressor
and blower. It is an automatically reset control. Its primary
function is to prevent damage to the compressor if a leak
develops in the refrigeration system. It may also open if
the unit is A) used in a cool area (below 50°F) and the
defrost timer is not adjusted or B) stored where it is below
40°F and then started. Under these conditions, the unit
will restart within several minutes; it may cycle several
times until the unit warms up.
3 Maintenance
3.1 Air Filter
The Phoenix Arctic Max is equipped with 2 pleated fabric
air filters that must be checked regularly. The cooling air
flow filter is a MERV-11 high efficiency filter. The condener
exhaust filter is a MERV-7. Operating the unit with a dirty
filter will reduce the dehumidifier’s capacity and efficiency
and may cause the compressor to cycle off and on
unnecessarily on the defrost control.
The filter can generally be vacuumed clean several times
before needing replacement. Replacement filters can be
ordered from the factory or purchased locally if available.
WARNING: DO NOT operate the unit without the filter or
with a less effective filter as the heat exchange coils inside
the unit could become clogged and require disassembly to
clean.
3.2 Storage
There are two issues to consider when the Phoenix Arctic
Max is stored between uses and both pertain to the
water trapped in the unit: damage caused by freezing or
biological growth.
The effect of the trapped water can be greatly reduced
if precautions are taken to remove as much as possible
before storage.
1. Use the pump purge switch to reduce the water level
in the reservoir.
2. Stretch the hose flat to drain it completely.
If the unit will not be exposed to freezing temperatures, an
alternative to reduce biological growth is to flush the unit
with a bio-fungicide that is approved for use with copper,
aluminum and polyethylene. To flush:
1. Run the hose to a drain.
2. Remove the air filter. Remove top and front cover.
Slowly pour a quart of the chemical through the
evaporator coil fins and drain into the drain pan.
3. Flush coil with water.
4. Hold in the pump purge switch to reduce the water
level in the reservoir.
4 Service
WARNING: Servicing the Phoenix Arctic Max with its high
pressure refrigerant system and high voltage circuitry
presents a health hazard which could result in death,
serious bodily injury, and/or property damage. Only
qualified service people should service this unit.
Do not operate unit without the front panel in place.
4.1 Technical Description
The Phoenix Arctic Max uses a refrigeration system similar
to an air conditioner’s to remove heat and moisture from
incoming air and to add heat to the air that is discharged.
Hot, high pressure refrigerant gas is routed from the
compressor to the condenser coil. The refrigerant is cooled
and condensed by giving up its heat to the air that is about
to be discharged from the unit. The refrigerant liquid then
passes through a filter/drier and capillary tubing which
Figure 4: Defrost timer
for operating in tempera-
tures below 50°F.
Figure 3: Defrost timer
for operating in tem-
peratures above 50°F.
