TemperZone OSA 175RKTHG Maintenance and service guide

OSA 175RKTHG (Digital)
Reverse Cycle R410A
Split System Outdoor Unit Installation &
Maintenance
REFRIGERATION PIPING
General
The OSA 175 is shipped with a refrigerant
charge sufficient for a 10 m line length.
The matched indoor unit is shipped with
a holding charge of nitrogen. OSA 175
units have one flare nut and one rotolock
assembly. Two loose pipe extensions are
supplied to enable a choice of exit – side or
rear; both require brazing.
Recommended Pipe Sizes
Suction pipe : 22 mm OD
Liquid pipe : 13 mm OD
Line Lengths
The standard unit allows for a line length
up to 30 m. For line lengths between 30 m
and 60 m, refer to temperzone's
Split Systems Installation Guide (refer
www.temperzone.biz/Technical Support).
Refer also to Oil Charge overleaf.
Maximum line length when extended is 60m.
Height Separation Limits
Outdoor Unit above Indoor Unit : 20 m
Outdoor Unit below Indoor Unit : 20 m
Vertical Risers
If the outdoor unit is to be installed above
the indoor unit, then the suction riser should
be trapped at the bottom of the vertical
rise and then again at 5 m (maximum)
intervals. This is to ensure oil return to the
compressor. The trap to be a 'swan neck'
curve in the pipe, with no change in the pipe
size.
Piping
1. Use clean sealed refrigeration grade
piping and accessories designed
specifically for R410A.
2. Cut pipe with a pipe cutter ONLY.
3. Use long radius bends (2x pipe dia.).
4. Insulate the suction (gas) line and seal
all insulation joints.
5. Bi-flow type filter dryer may be fitted in
the liquid line.
6. Include a process point in the
interconnecting pipework.
7. Ensure open pipe ends are sealed until
the final connection is made.
8. Caution: To avoid damage to teflon
seals, braze suction pipework to stub
connection (supplied loose) before
connecting to unit's valve.
9. Remove valve's dust cap and lubricate
teflon seal with refrigeration oil prior to
final assembly and connection.
Free Standing :
Fasten the unit down to a firm flat horizontal
base using the four holes provided in the
mounting rails. To avoid transfer of vibration,
mount the unit on the optional rubber
mounts available from temperzone.
When the unit is being installed on a roof
it is recommended that the unit is installed
on a substantial structure with vibration
isolating springs or rubber mounts (optional
extra) beneath the unit. These items are not
supplied with the unit.
Wall Mounting Option:
Complete wall mounting instructions are
supplied with the optional wall mounting kit.
Drain
Four drain holes are provided in the base.
Three plastic bungs are supplied (loose)
should you want to direct the condensate
and/or rain water to one of the holes
provided. Drain connection adaptors (25/13)
are available as an optional extra.
GENERAL
This OSA 175RKTHG Outdoor Unit must be
installed in accordance with all national and
local safety codes.
Options
1. Vertical discharge grille (2 required).
2. Wall mounting brackets.
3. Anti-vibration mounts (rubber).
4. Drain connection adaptors - right angle.
INSTALLATION
Positioning
Refer to dimension diagram below for
minimum clearances. Position the unit so
that prevailing winds do not blow onto the
exhaust to slow the fan, and one unit does
not exhaust toward the inlet of another unit.
The optional vertical discharge grilles can be
used to deflect prevailing winds and reduce
clearances.
Mount either free standing or on a wall using
the optional mounting brackets available.
Dimensions (mm) OSA 175RKTHG
PROJECTION
Not to Scale
Net Weight 131 kg
765 MTG CTR
12 DIA. HOLE+SLOT
ACCESS
PANEL
375
MTG CTR
420
OVERALL
REFRIG.
CONN’S
25 DIA.
ELECTRICAL
CONDUIT
HOLES
1125
OVERALL
1125
OVERALL
72
150 MIN. CLEARANCE
150 MIN. CLEARANCE
2000 MIN. CLEARANCE *
750 MIN. CLEARANCE
25 DIA.
DRAIN
HOLES
200 27
25 DIA.
DRAIN
HOLES
* 600 min with optional Vertical Discharge Grille

10. Touch up any outdoor unit paintwork
damage to prevent corrosion.
OUTDOOR UNIT CONTROLLER (OUC)
The Outdoor Unit Controller (OUC)
includes a temperature sensing head
pressure control which enables the system
to compensate for outdoor ambient
temperatures below 20°C, and heating cycle
above 15°C. The OUC also has features
which protect against icing or overheating
of coils, rapid cycling of the compressor and
loss of refrigerant charge.
If the outdoor unit fans take some time
to begin rotating when the system is
powered on, or they don't appear to be
rotating appropriately while the compressor
is running, consult the OUC label on
the electrical box. If necessary, refer
to temperzone for further diagnostic
information.
MAINTENANCE
Weekly For First Four Weeks
1. Check indoor unit air filters (if fitted) and
vacuum or wash clean as necessary.
2. Check condensate drain for free
drainage.
3. Check compressor compartment for oil
stains indicating refrigerant leaks.
4. Check tightness of electrical
connections.
Six Monthly
1. Check the tightness of all fan and motor
mountings.
2. Check tightness of electrical
connections.
3. Check that fan motors are free running.
4. Check suction and discharge operating
pressures.
5. Replace indoor unit air filters (if fitted).
6. Check condensate drain for free
drainage.
Yearly
1. Check all refrigerant piping for chafing
and vibration.
2. Check the operation of electric heaters if
fitted.
3. Check air supply at all diffusers.
4. Check for excessive noise and vibration
and correct as necessary.
5. Check for insulation and duct damage
and repair as necessary.
6. Remove lint and dust accumulation from
outdoor coil fins.
7. Touch up all outdoor unit paintwork
damage to prevent corrosion.
NOTE
The manufacturer reserves the right to
change specifications at any time without
notice or obligation. Certified dimensions
available on request.
This pamphlet replaces the previous
issue no. 3327 dated 02/10.
Extra drain holes.
Standard units are suitable for use with
thermostats with either manual Heat/Cool
selection or automatic changeover subject
to the contact ratings of the thermostats.
Refer to temperzone for recommended
thermostats.
Note: The TZT-701 Controller can
automatically switch the indoor fan off during
de-ice, if selected, therefore no additional
wiring is required to achieve this result.
A 24 hour power supply is required to the
unit. Disconnect the crankcase heater if the
total line length is less than 8 m.
SYSTEM CHECK TESTS
1. Leave the remote switch in the off
position and close the mains isolating
switch.
A four hour delay period is required to
allow the crankcase heater to drive any
liquid refrigerant out of the compressor
oil.
2. Check that all fan motors are free
running.
3. Check for correct rotation of the
compressor. If rotation is incorrect
the compressor will not pump and will
draw minimal current. To correct motor
rotation, change the phasing at the main
power terminal.
4. Check that the thermostat is correctly
wired to the unit and is set at the desired
temperature.
5. Check that the air filters, if any, have
been correctly installed.
6. Check any supply air diffuser dampers
are open.
START UP PROCEDURE
Use the supplied Commissioning Sheet to
help you complete the following procedure:
1. Switch on the unit after the four hour
delay period for the crankcase heater
has expired.
2. Check the supply voltage.
3. Measure the current draw on the
compressor motor and on each fan
motor. Check all readings against the
specified values - particularly the indoor
fan amps if the unit is installed in a free
blow application.
4. Fit gauges and measure the suction and
discharge pressures.
Important: Gauges must be designed
specifically for use with R410A.
5. Test the operation of the high pressure
safety control by switching off the
outdoor unit's fan.
6. Test the operation of the reversing valve
by running the unit in both the heating
and cooling mode.
7. Check that the air flow over the outdoor
unit's coil is adequate and that the fan is
running smoothly.
8. Check the superheat - refer charging
procedure.
9. Check the supply air flow at each outlet.
Charging
The unit is supplied with 4.1 kg of refrigerant
HFC-410A (R410A) which is sufficient for
10 m of pipework when connected to the
ISD 175KG-DN indoor and outdoor units.
Add, or subtract, 60 g of HFC-410A per
metre to suit the installed line length.
Charging (cont'd)
Procedure:
1. Evacuate Indoor Unit and
interconnecting pipework to a pressure
of 500 microns and hold for 15 mins.
2. Add refrigerant, if needed, via the
Schraeder connection on the rotolock
and flare pipe assemblies.
3. Open the service valve at the Outdoor
Unit to allow refrigerant to flow
throughout the system.
4. Leak check all brazed and fitted joints.
IMPORTANT :
Step 8 of the 'Start Up Procedure' requires
you to check that the superheat on the
suction line (where it enters the Outdoor
Unit) is between 3°C – 5°C on cooling cycle
with an indoor air temperature in the range
21° – 27°C and outdoor air temperature in
the range 24° – 35°C. If the conditions of
the day do not allow this, use the heating
cycle (on a reverse cycle unit) or other heat
source to raise the indoor air temperature
to about 24°C and blank off the outdoor
coil to raise the head pressure to 400 psig
(2760 kPag). Alter charge up or down to
establish correct superheat.
WARNING:
This unit is designed for use ONLY with the
refrigerant HFC-410A (R410A). The use
of other refrigerants is NOT authorised or
approved by the manufacturer and may
cause operational problems such as poor
performance and efficiency, loss of capacity,
degradation of materials and refrigerant
leaks. The use of flammable or explosive
materials as a refrigerant creates the
additional risks of fire and explosion
which may result in property damage,
personal injury or death.
Oil Charge
For line lengths in excess of 30 m, Emkarate
RL22CF polyolester oil (or similar) should
be added to the refrigerant at the rate of
13 ml/m of suction piping. Note: Do not use
mineral oil.
ELECTRICAL REQUIREMENTS
Electrical work must be done by a qualified
electrician. The outdoor unit must be wired
directly from a distribution board by means
of a circuit breaker or H.R.C. fuse, and a
mains isolator provided - preferably close to
the Outdoor Unit.
Note: DO NOT USE REWIRABLE FUSES.
Pipe Size (mm) Equivalent Line Pipe Length (m)
Liquid
13
Pipe Length Capacity Loss
On Cooling Cycle Due to Pressure Drop
Note : Loss percentages are approximations only, due to piping variations. No allowance made for vertical piping.
Suction
22
5
0.7 %
22 mm
0.5 m
20
4.7 %
10
2.1 %
15
3.4 %
30
6.1 %
Suction Pipe Size OD
Long 90° Radius (2 x pipe dia.)
Additional Pipe Length to allow per Bend

© temperzone limited 2010 05/10 Pamphlet No. 3382