DEC PHOENIX 300 Operation manual

Lit. No. TS-218B-0499
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
Therma-Stor Products
A Division of DEC International
Box 8050 Madison, WI 53708
Toll Free 1-800-533-7533
Local 1-608-222-5301 
PHOENIX 300 Operation & Service Instructions
Table of Contents
1. Specifications................................................... 1
2. Operation .......................................................... 1
2.1 Transporting the Phoenix 300 ...................... 1
2.2 Location ........................................................ 1
2.3 Electrical Requirements ............................... 2
2.4 Condensate Removal ................................... 2
2.5 Ducting ......................................................... 2
2.6 Power Switch................................................ 2
2.7 Pump Purge Switch ...................................... 2
2.8 Pump Fail Light............................................. 2
2.9 Hour Meter.................................................... 2
2.10 Defrost Control Adjustment ......................... 2
2.11 Low Pressure Control .................................. 3
3. Maintenance ..................................................... 3
3.1 Air Filter ........................................................ 3
3.2 Blower Oiling ................................................ 3
3.3 Storage ......................................................... 3
4. Service .............................................................. 4
4.1 Warranty....................................................... 4
4.2 Technical description.................................... 4
4.3 Troubleshooting............................................ 4
4.4 Refrigerant Charging .................................... 5
4.5 Blower Replacement .................................... 5
4.6 Compressor/Capacitor Replacement ........... 5
4.6A Checking Compressor Motor Circuits ..... 5
4.6B Replacing a Burned Out Compressor .....6
4.6C Replacing a Compressor- Non-Burn Out ... 7
4.7 Defrost Thermostat & Timer......................... 7
4.8 Condensate Pump........................................ 7
4.9 Relay............................................................. 7
4.10 Time Delay .................................................. 7
5. Wiring Diagram................................................. 8
6. Service Parts List ............................................. 9
Serial No. ________________________________
Purchase Date ____________________________
Dealer's Name ____________________________
Read the operation and maintenance instructions
carefully before using this unit. Proper adherence to
these instructions is essential to obtain maximum
benefit from your Phoenix 300 dehumidifier.
1 Specifications
Model: PHOENIX 300 Dehumidifier
Electrical: 110-120 Vac, 12 Amps, grounded
Capacity: 176 pints per day @ 80°F, 60% RH
Operating Temp. Range: 33°F min., 105°F max.
Air Flow: 540 CFM without external ducting
Refrigerant Charge: 2 lbs., 5 oz. R-22
Optional Duct connection: 10" round outlet
Size: 45" high x 24" wide x 20" deep cabinet
46" high x 29" wide x 25" deep overall
Weight: 175 lbs.
2 Operation
2.1 Transporting the Phoenix
The Phoenix 300 must always be upright when
transported by vehicle. It may be tipped on to its handle
and back for loading and moving by hand.
2.2 Location
Note the following precautions when locating the
Phoenix 300:
•It is designed to be used INDOORS ONLY.
•If used in a wet area, plug it into a GROUND FAULT
INTERRUPTER.
•
••
•DO NOT use the Phoenix 300 as a bench or table.
•It must always be used in the upright position.
•The air inlet on top & the side outlet must be at least
1 foot from walls and other obstructions to air flow.
•If the humid area is very large, dehumidification can
be improved by adding an outlet duct to circulate air
to stagnant areas (see Sec. 2.5).

2
2.3 Electrical Requirements
The Phoenix 300 can be plugged into a grounded 15
Amp circuit. At 80°F, 60% RH, it draws 11.4 Amps. Due
to the high percentage of a 15 Amp circuit’s capacity
that the unit uses, the circuit should be dedicated to
running it only. Amp draw decreases at lower loads and
increases at higher loads. At extremely high loads, a 20
Amp circuit may be required.
The unit briefly draws more amps to start if it has been
stored in a cold area. This may cause a 15 Amp circuit
breaker to trip. A 20 Amp circuit is recommended in
such situations. Some models have a time delay to
delay the compressor start about 2 minutes after the
power switch is turned on. This reduces the unit’s
starting amp draw by starting the blower and
compressor at different times.
If an extension cord is required, it must have a
minimum of 12 gauge conductors if 25 feet long or less
and 10 gauge conductors if greater than 25 feet long.
2.4 Condensate Removal
The Phoenix 300 is equipped with an internal
condensate pump to remove the water that is
condensed during dehumidification. This allows the
condensate to be pumped 30' with the attached hose. If
the condensate must be pumped more than 20 feet
above the unit, a second pump must be added to relay
the condensate.
2.5 Ducting
A detachable 10" round exhaust collar is supplied that
will allow a 10” round flexible duct to be attached to the
Phoenix 300 outlet. The duct and collar may be quickly
attached to the Phoenix 300 by sliding the 4 collar tabs
into the slots around the blower outlet and rotating the
collar clockwise. It may be quickly removed to transport
the unit more easily.
2.6 Power Switch
The power switch (on left side of hour meter) lights up
when the unit is turned on. The unit will continue to run
in all conditions until the switch is turned off; there is no
dehumidistat.
2.7 Pump Purge Switch
This switch (on right side of hour meter) minimizes the
water left in the condensate pump reservoir for moving
or storage. Pressing and holding the pump purge
switch will cause the condensate pump to run. Hold the
switch in until the flow from the condensate hose stops.
2.8 Pump Fail Light
If the condensate pump fails, water draining into the
pump reservoir will fill above its normal level. A safety
float switch will then turn on the pump fail light (located
next to the pump purge switch) and stop the
compressor. This prevents water from overflowing and
wetting the floor. The safety switch will not allow the
compressor to restart until water has been removed
from the pump reservoir.
2.9 Hour Meter
The digital hour meter measures the cumulative time
that the unit is turned on to tenths of an hour. It stores
its total when the unit is unplugged; the previous total
will be displayed when the unit is next turned on. It
resets to zero after 99,999.9 hours of operation.
2.10 Defrost Control Adjustment
When the Phoenix 300 is used in a cool area, frost will
form on the cooling coil as it dehumidifies. When
enough frost forms, the defrost thermostat will initiate
the timed defrost cycle. The cycle periodically turns off
the compressor while allowing the blower to run. The
frost is melted by the air that the blower draws through
the cooling coil.
The defrost cycle is automatic and designed for
optimum performance above 50°F. If the unit is used in
an area that is below 50°F for more than 2 hours,
adjustment of the defrost timer is recommended to
improve performance (see Sec. 2.10).
DRYING TIP: Air’s ability to absorb moisture from wet
surroundings and the Phoenix 300’s ability to remove
moisture from that air is greatly improved at higher
temperatures. We recommend that the area to be dried
be heated to over 70°F if possible. Less drying time will
be required and efficiency will improve.
To adjust the defrost timer:
1. Unplug the unit.
2. Remove the front cover (6 screws).
3. The timer is fastened to the right inside panel.
Every fourth peg around the dial is pushed out
from the dial center except one section with 5
pegs out in a row. See figure 1. Each fourth “out”
peg represents 15 minutes of compressor "off"
time during every hour that the unit is in the
defrost cycle.
4. To improve performance below 50°F, the
compressor "off" time must be increased to 30
minutes per hour to allow the frost to completely
melt. To do this, push the pegs out from the dial

3
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 (see Fig. 1).
5. Replace the cover.
Change the timer pegs back to the original pattern for
use above 50°F.
Figure 1: Defrost Control Timer
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
(see Sec. 2.10) or B) stored where it is below 40°F and
then started. Under these conditions, the unit will
restart within several minutes. Until the unit warms up,
it may cycle several times.

4
3 Maintenance
3.1 Air Filter
The Phoenix 300 is equipped with a 4” thick, 35%
efficient pleated fabric air filter that must be checked
regularly. 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.
Two optional filters are available: A) a 2” pleated filter
that has the same efficiency as the 4” standard filter,
but less surface area. This filter would need to be
changed more often than the 2” version. B) a 95%
efficient 4” filter that acts as an air scrubber to catch
mold and mildew spores.
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. 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 Blower Oiling
The blower motor is lubricated for life from the factory
and does not require oiling by the owner.
3.3 Storage
There are two issues to consider when the Phoenix
300 is stored between uses and both pertain to the
water trapped in the unit: damage caused by freezing
and 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 (see Sec. 2.7 & Fig. 4)
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 way 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. Plug in the unit but do not turn it on.
3. Remove the air filter. Slowly pour a quart of the
chemical through the top grille so that it drains into
the white plastic slots.
4. Hold in the pump purge switch to reduce the water
level in the reservoir.
4 Service
CAUTION: Servicing the Phoenix 300 with its high
pressure refrigerant system and high voltage circuitry
presents a health hazard that could result in death,
serious bodily injury, and/or property damage. Only
qualified service people should service this unit.
4.1 Warranty
A warranty certificate has been enclosed with this unit;
read it before any repair is initiated.
If a warranty repair is required, call the factory first at 1-
800-533-7533 for warranty claim authorization and
technical assistance.
4.2 Technical Description
The PHOENIX 300 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 (see Fig. 2).
Hot, high pressure refrigerant gas is routed from the
compressor to the condenser coil (see Figure 2). 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 cause the
refrigerant pressure and temperature to drop. It next
enters the evaporator coil where it absorbs heat from
the incoming air and evaporates.
The evaporator operates in a flooded condition, which
means that all the evaporator tubes contain liquid
refrigerant during normal operation. A flooded
evaporator should maintain constant pressure and
temperature across the entire coil, from inlet to outlet.
The mixture of gas and liquid refrigerant enter the
accumulator after leaving the evaporator coil. The
accumulator prevents any liquid refrigerant from
reaching the compressor. The compressor evacuates
the cool refrigerant gas from the accumulator and
compresses it to a high pressure and temperature to
repeat the process.

5
Figure 2: Refrigeration system of Phoenix
4.3 Troubleshooting
No dehumidification. Neither blower or compressor
run. Power switch does not light when ON.
1. Unit unplugged or no power to outlet.
2. Power switch defective (Sec. 2.6).
3. Loose connection in internal wiring (Fig. 3).
No dehumidification. Neither blower or compressor
run. Power switch ON & lit.
1. Low pressure control open (Sec. 2.11).
2. Power switch defective (Sec. 2.6).
3. Loose connection in internal wiring (Fig. 3).
Some dehumidification, blower runs continuously
but compressor only runs sporadically.
1. Unit is in defrost cycle (Sec. 2.10 & 4.7).
2. Defrost thermostat defective or loose
(Sec. 2.10 & 4.7).
3. Loose connection in compressor circuit
(see Fig. 3).
4. Defective compressor overload (Sec. 4.6A).
5. Defective compressor (Sec. 4.6).
6. Defective relay (Sec. 4.9).
7. Defective time delay (Sec. 4.10).
No dehumidification. Blower runs but compressor
does not. Pump fail light not lit.
1. Bad connection in compressor circuit (Fig. 3).
2. Defective compressor capacitor (Sec. 4.6A).
3. Defective compressor overload (Sec. 4.6A).
4. Defective compressor (Sec. 4.6).
5. Defective relay (Sec. 4.9).
6. Defective time delay (Sec. 4.10).
No dehumidification. Pump Fail Light lit. Blower
runs but not compressor.
1. Bad connection in pump circuit (Fig. 3).
2. Pump float switch or safety switch defective
(Sec. 4.8).
3. Pump motor defective (Sec. 4.8).
Blower does not run. Compressor runs briefly but
cycles on & off.
1. Loose connection in blower circuit (Fig. 3).
2. Obstruction prevents impeller rotation.
3. Defective blower (Sec. 4.5).
Unit removes some water but not as much as
expected.
1. Air temperature and/or humidity have dropped.
2. Humidity meter and/or thermometer used are out
of calibration.
3. Unit has entered defrost cycle (Sec. 2.10 & 4.7).
4. Air filter dirty (Sec. 3.1).
5.Defrost timer incorrectly set for conditions (Sec.
2.10 & 4.7).
6.Defective defrost thermostat (Sec. 4.7)
7. Low refrigerant charge (Sec. 4.4).
8. Air leak such as loose cover.
9. Defective compressor (Sec. 4.6).
10. Restrictive exhaust ducting (Sec. 2.5)
Unit runs but does not pump water.
1. Hose kinked or plugged.
2. Pump check valve plugged (Sec. 4.8).
3. Bad connection in pump circuit (Fig. 3).
4. Hose disconnected internally.
Unit pumps water automatically but not when
purge switch is pushed.
1. Bad connection in purge switch circuit
(Fig. 3).
2. Defective purge switch (Sec. 2.7).
Evaporator coil frosted continuously, low
dehumidifying capacity.
1. Defrost thermostat loose or defective
(Sec. 2.10 & 4.7).
2. Defrost timer incorrectly set or defective
(Sec. 2.10 & 4.7).
2. Low refrigerant charge (Sec. 4.4).
3. Dirty air filter or air flow restricted. (Sec. 3.1).
Compressor runs with power switch OFF.
1. Defective relay (Sec. 4.10).
2. Defective power switch (Sec. 2.6)
4.4 Refrigerant Charging
If the refrigerant charge is lost, a new charge must be
accurately weighed in. If any of the old charge is left in
the system, it must be removed before weighing in the
new charge. Refer to the unit nameplate for the correct
charge weight and refrigerant type.

6
4.5 Blower Replacement
The centrifugal blower has a PSC motor and internal
thermal overload protection. If defective, the complete
assembly must be replaced.
1. Unplug the power cord.
2. Remove the cabinet front (6 screws).
3. Disconnect the blower leads.
4. Pull the oil tubes out of the motor.
5. Tip the unit on its back. From the bottom, remove
the 2 screws that fasten the blower housing to
the base.
6. Remove the four screws holding the blower outlet
flange to the cabinet end.
7. Remove the blower. Use care to avoid hooking
wiring, tubing or electrical components.
8. Reassembling with the new blower is the above
procedure reversed.
4.6 Compressor/Capacitor
Replacement
This compressor is equipped with a two terminal
external overload, run capacitor, but no start capacitor
or relay (see Fig. 3).
CAUTION-ELECTRICAL SHOCK HAZARD: Electrical
power must be present to perform some tests; these
tests should be performed by a qualified service
person.
4.6A Checking Compressor Motor Circuits
Perform the following tests if the blower runs but the
compressor does not with the power switch ON.
1. Turn the power switch OFF and unplug the unit,
remove the cabinet front (6 screws).
2. Plug in the unit and turn the power switch ON.
Use a voltmeter to check for 110 to 120 volts
between (a) the relay terminal that the black wire
from the compressor connects to and (b) the
capacitor terminal with the (3) white wires & (1)
red wire connected. If voltage is present, go to
step 3. If no voltage, the low pressure control, the
time delay or the relay are open or there is a
loose connection in the compressor circuit. Test
each component for continuity; see the
appropriate section if a defect is suspected.
3. Turn the power switch OFF and unplug the unit,
then disconnect the red and yellow wires from
compressor terminals R & S. Using an
ohmmeter, check continuity between the points
listed below.
4. Compressor terminals C and S: No continuity
indicates an open start winding; the compressor
must be replaced.
5. Compressor terminals C and R: No continuity
indicates an open run winding; the compressor
must be replaced.
6. Compressor terminal C and overload terminal 1:
No continuity indicates a defective overload lead.
7. Overload terminals 1 and 3: If there is no
continuity, the overload may be tripped; wait 10
minutes and try again. If there is still no
continuity, it is defective and must be replaced.
8. Compressor terminal C and compressor case:
Continuity indicates a grounded motor; the
compressor must be replaced.
9. Disconnect the wires from the capacitor. Set the
ohmmeter to the Rx1 scale; the capacitor is
shorted and must be replaced if continuity exists
across its terminals. If there is no needle
movement with the meter set on the Rx100000
scale, the capacitor is open and must be
replaced.
10. Reconnect the wires to the compressor and
capacitor; plug in and turn on the unit. If the
compressor fails to start, replace the run
capacitor.
11. If the unit still does not start, adding a hard-start
kit will provide greater starting torque. If this does
not work, the compressor has an internal
mechanical defect and must be replaced.
4.6B Replacing a Burned Out Compressor
The refrigerant and oil mixture in a compressor is
chemically very stable under normal operating
conditions. However, when an electrical short occurs in
the compressor motor, the resulting high temperature
arc causes a portion of the refrigerant oil mixture to
break down into carbonaceous sludge, a very corrosive
acid, and water. These contaminants must be carefully
removed otherwise even small residues will attack
replacement compressor motors and cause failures.
The following procedure is effective only if the system
is monitored after replacing the compressor to insure
that the clean up was complete.
1. This procedure assumes that the previously listed
compressor motor circuit tests revealed a shorted
or open winding. If so, cautiously smell the
refrigerant from the compressor service port for
the acid odor of a burn out. WARNING: The gas

7
could be toxic and highly acidic. If no acid odor is
present, skip down to the section on changing a
non-burn out compressor.
2. Remove and properly dispose of the system
charge. DO NOT vent the refrigerant or allow it to
contact your eyes or skin.
3. Remove the burned out compressor. Use rubber
gloves if there is any possibility of coming in
contact with the oil or sludge.
4. To facilitate subsequent steps, determine the type
of burn out that occurred. If the discharge line
shows no evidence of sludge and the suction line
is also clean or perhaps has some light carbon
deposits, the burn out occurred while the
compressor was not rotating. Contaminants are
therefore largely confined to the compressor
housing. A single installation of liquid and suction
line filter/driers will probably clean up the system.
If sludge is evident in the discharge line, it will
likely be found in the suction line; this indicates
the compressor burned out will running. Sludge
and acid have been pumped throughout the
system. Several changes of the liquid and suction
filter/driers will probably be necessary to cleanse
the system.
5) Correct the system fault that caused the burn out.
Consult the factory for advice.
6) Install the replacement compressor with a new
capacitor and an oversized liquid line filter.
In a running burn out, install an oversized suction
line filter/drier between the accumulator and
compressor. Thoroughly flush the accumulator
with refrigerant to remove all trapped sludge and
to prevent the oil hole from becoming plugged. A
standing burn out does not require a suction line
filter/drier.
7) Evacuate the system with a good vacuum pump
and accurate vacuum gauge. Leave the pump on
the system for at least an hour.
8) Operate the system for a short period of time,
monitoring the suction pressure to determine that
the suction filter is not becoming plugged.
Replace the suction filter/drier if pressure drop
occurs. If a severe running burn out has occurred,
several filter/driers may have to be replaced to
remove all of the acid and moisture.
NOTE: NEVER use the compressor to evacuate
the system or any part of it.
4.6C Replacing a Compressor- Non-Burn
Out
Remove the refrigerant from the system. Replace the
compressor and liquid line filter/drier. Charge the
system to 50 PSIG and check for leaks. Remove the
charge and weigh in the refrigerant quantity listed on
the nameplate. Operate the system to verify
performance.
4.7 Defrost Thermostat & Timer
The defrost thermostat is attached to the refrigerant
suction tube between the accumulator and
compressor. If the low side refrigerant temperature
drops due to excessive frost formation on the
evaporator coil, the thermostat opens. The
compressor is then cycled off and on by the defrost
timer. The blower will continue to run, causing air to
flow through the evaporator coil and melt the ice when
the compressor is off. When the air temperature and/or
humidity increase, the evaporator temperature will rise
and the thermostat will close to end the defrost cycle.
To improve performance in low temperatures, see Sec.
2.9 for defrost timer adjustment.
4.8 Condensate Pump
Condensate is automatically pumped when the water
level in the pump's reservoir rises to close the float
switch or if the pump purge switch is held in.
If the pump is unable to empty its reservoir due to a
pump failure or blocked condensate hose, a pump
safety float switch is triggered before the reservoir
overflows. The switch turns on the pump fail light &
turns off the compressor via its relay.
To replace the condensate pump:
1. Unplug the unit & remove the front cover.
2. Disconnect the 2 hoses from the pump.
3. Cut the pump lead wires near the old pump.
4. Remove the 4 screws from the unit bottom that
hold the pump to the base.
5. Attach the new pump with 4 screws.
6. Connect the new pump wiring. It may be easier
to splice the new & old gray leads together with a
wire nut, and splice the new & old yellow leads
together, rather than route the new ones to the
pump purge switch & pump fail light.
7. Connect the hoses to the new pump. Carefully
route the hoses so they do not contact the
copper refrigerant lines or the compressor shell.

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4.9 Relay
The contacts of the single pole, single throw relay
complete the power circuit to the compressor. The
contacts are closed when power is provided to the relay
coil via the control circuit. The control circuit includes
the power switch, low pressure control, time delay (HP
model), defrost thermostat and timer.
4.10 Time Delay (HP model only)
The HP model has a time delay relay in the
compressor control circuit. This relay delays the
compressor start about 2 minutes after the power
switch is turned on. This reduces the unit’s starting
amp draw by starting the blower and compressor at
different times. This reduces the chance of tripping a
circuit breaker during hard start situations, such as
when the unit has been stored in a cold place. It also
reduces compressor short cycling after the compressor
has stopped.

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Figure 3: Electrical Schematic of Phoenix 300

10
SERVICE PARTS LIST: Phoenix 300 Dehumidifier
ITEM PART NO. QTY. DESCRIPTION
1 4021818 1 Accumulator
2 4022636 1 Air Filter, Pleated, 2” x 20” x 20” (Grainger P/N 6B937)
4022614 1 Air Filter, Pleated, 4” x 20” x 20” (Grainger P/N 2W236)
4022624 1 Air Filter, Pleated, 4” x 20” x 20” (90-95% EFFICIENT)
3 4021083 1 Blower w/ Capacitor (Fasco 7074-2778)
4 4022622 2 Bumper, Foot, 1.50 Dia. x .75 High
5 4017777 2 Capillary Tubes, .059" ID x .124” OD x 32" long
6 4022563 1 Coil, Condenser
7 4022557 1 Coil, Evaporator
8 4022600 1 Compressor, Carlyle (P/N EBA135111A)(HP Model)
4023645 1 Compressor, Carlyle (P/N EBA120111A)
9 4022595 1 Compressor Overload, Carlyle (included with compressor)
10 4022635 1 Condensate Pump
11 4022615 1 Cord & Wire Harness
12 4021908 1 Drain Hose (.38 ID x .56 OD x 33' long)
13 4022611 1 Outlet Collar (for Ducting Outlet)
14 4022593 1 Filter/Drier (not shown)
15 4021597 1 Hour Meter
16 4021089 1 Indicator Light, Red, 125V
17 4022616 1 Instruction Label (not shown)
18 4022219 1 Low Pressure Control (Ranco P/N 070-127000-D01)
19 1970010 1 Relay (Grainger P/N 4A711)
20 4022740 1 Run Capacitor, 30 MFD, 370V
21 4021997 6 Spring
22 4021796 1 Switch, Pump Purge
23 4021822 1 Switch, Power
24 4021470 1 Thermostat, Defrost
4021648 1 Thermostat, Defrost, Mounting Clip
25 4021823 1 Timer, Defrost
26 4022878 1 Time Delay (HP Model)
27 4022613 2 Wheel, 12", Plastic
28 4022597 1 Wiring Diagram (on Cover)(not shown)
29 4021950 1 Ground Fault Interrupter (optional) (not shown)
30 4023079 1 Coupling, Body, Quick Connect, .38 Tube (not shown)
31 4023080 1 Coupling, Insert, Quick Connect, .38 Tube (not shown)
Figure 4