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RT-SVX50M-EN

27

Low Ambient Operation (Optional)

During low ambient operation, outside air temperature
below 50°F, the Low Ambient Controller will cycle the
outdoor fan motor "Off" and "On" based on discharge
pressure. The indoor fan motor (IDM) will continue to
operate and the outdoor fan will return to normal operation
once the ambient temperature is above 50°F.

Two-Speed Indoor Fan Control

For units equipped with two-speed indoor fan control,
standard unit operation for cooling and heating will
continue and all unit functions will operate normally, except
for the control of the indoor fan speed. All units configured
with any type of heating will heat the supply air and space
as normal utilizing full speed indoor fan by energizing the
appropriate outputs. The two-speed indoor fan unit will only
utilize two speeds during the cooling operation modes
described below.

Cooling Operation

For cooling operation, the unit will operate at Low Fan
Speed during Fan Only, Economizer Only, and the first
stage of compressor unit modes by Default. When the unit
receives a call for cooling, if the economizer is enabled, the
unit will energize the associated Low Speed output and
begin to modulate the OA Damper open above minimum
position up to 100% as necessary. By default, the supply
fan will remain at low speed for the duration of Economizer-
Only cooling. If the supply fan is on when the first stage
compressor is energized, it will remain energized or
energize at low speed for the duration of Cool 1.

When there is a call for Cool 2, the second compressor is
energized and the Supply Fan will switch to High Speed.

The unit will stage down compressors for cooling in reverse
order that they were staged and the supply fan will follow
the unit mode transitions. Once it is determined through
normal cooling control that the second compressor is no
longer necessary to meet cooling demand, the second
compressor will be staged back and the supply fan will
switch to Low Speed until the unit stages all cooling off or
receives a call for Cool 2 again. Once the Supply Fan is no
longer requested ON after a Cooling call is cleared, the
Supply Fan will remain energized at Low Speed for 60
seconds as on traditional units.

If the economizer is enabled and is being utilized as the
first stage of cooling (Y1 active), if the unit receives a Y2
request, the unit will energize the first compressor and will
switch the supply fan to high speed until the Y2 request is
cleared.

Economizer Minimum Position Handling
for 2–Speed Fan

Due to the low and high speeds of the indoor fan, when the
unit is in Fan Only, Cool 1, or Economizer Only and the
indoor fan is at low speed, the unit will not be bringing in as
much fresh air as normal. By setting a higher minimum

damper position this problem could be solved, but that
would mean more fresh air than may be desired when the
supply fan is at high speed. To overcome these situations,
the control will require the setting of two economizer
minimum positions to be used when the fan is at low and
high speed to compensate for the lower amount of fresh air
at lower fan speeds and the potential for more fresh air
than desired at higher fan speeds. These minimum
positions will be obtained from the Bldg Design Min
Position and DCV Min Position pots on the RTEM-EM. The
economizer minimum position that will be utilized while the
supply fan is at low speed will be set with the DCV Min
Position pot with a range of 0-100% and the minimum
position that will be utilized while the supply fan is at high
speed will be set with the Building Design Min Position pot
with a range of 0-50%. If the Building Design Min Position
is set to be higher than the DCV Min Position, the setpoints
will be capped at the DCV Min Position and the setpoint for
the min position at low and high fan speed will be the DCV
Min Position.

Phase Monitor

The phase monitor is a three-phase line monitor module
that protects against phase loss, phase reversal and phase
unbalance. It is intended to protect compressors from
reverse rotation. It has an operating input voltage range of
180-600 Vac, and LED indicators for ON and FAULT. There
are no field adjustments and the module will automatically
reset from a fault condition.

Low Pressure Cutout

The low pressure cutouts are wired in series with the high
pressure cutouts and the temperature discharge limits. If
this circuit is open before a compressor is started, the
compressor in that circuit will not be allowed to operate.

Anytime this circuit is opened, the compressor in that circuit
is turned off immediately.

High Pressure Cutout and Temperature
Discharge Limit

The high pressure controls and temperature discharge limit
are wired in series between the compressor outputs on the
LTB and the compressor contactors. If the high pressure
safety or temperature discharge limit opens, the
compressor on the affected circuit is turned off.

Locking Safety Device with Compressor
Anti Short Cycle Timer

This device monitors compressor safety switch trips to
prevent short cycling, protecting the compressor. A manual
reset is required after a fourth safety switch trip.

Coil Frost Protection

The Frostat™ control monitors the evaporator coil
temperature to prevent the evaporator from freezing due to
low operating temperatures whenever there is a demand
for cooling. When a open circuit has occurred, the Frostat

Start Up

Содержание Foundation ECC180-300

Страница 1: ...properly installed adjusted or altered equipment by an unqualified person could result in death or serious injury When working on the equipment observe all precautions in the literature and on the tags stickers and labels that are attached to the equipment December 2022 RT SVX50M EN Installation Operation and Maintenance Packaged Rooftop Air Conditioners Foundation Cooling Only and Electric Heat 1...

Страница 2: ...at is used in these service procedures In addition some states or municipalities may have additional requirements that must also be adhered to for responsible management of refrigerants Know the applicable laws and follow them WARNING Proper Field Wiring and Grounding Required Failure to follow code could result in death or serious injury All field wiring MUST be performed by qualified personnel I...

Страница 3: ...stems By carefully reviewing the information within this manual and following the instructions the risk of improper operation and or component damage will be minimized It is important that periodic maintenance be performed to help assure trouble free operation A maintenance schedule is provided at the end of this manual Should equipment failure occur contact a qualified service organization with q...

Страница 4: ...Belt Drive Indoor Fan 25 Electromechanical Controls Test Procedure 25 Start Up 26 Electromechanical Controls Sequence Of Operation 26 Cooling without an Economizer 26 Evaporator Fan Operation for Cooling Only Units Standard Economizer 26 Economizer Set Up Standard Economizer 26 Cooling with an Economizer Standard Economizer 26 Heating Operation Units with Electric Heat Standard Economizer 26 Drain...

Страница 5: ...8 Standard Troubleshooting 38 Failures 38 Low Leak Economizer LLE Troubleshooting 38 Resetting Cooling and Heating Lockouts 39 Method 1 39 Method 2 39 Condensate Overflow Switch 39 Unit Economizer Control ECA 39 Error Code 39 Wiring Diagrams 40 Warranty 41 For Commercial Unitary Equipment Rated 25 Tons and Under and Related Accessories 41 Basic Warranty 41 Exclusions and Limitations 41 Table of Co...

Страница 6: ...0 with Barometric Relief1 J Downflow Low Leak Economizer Dry Bulb w o Barometric Relief L Downflow Low Leak Economizer Reference Enthalpy w o Barometric Relief N Downflow Low Leak Economizer Comparative Enthalpy w o Barometric Relief Digit 15 Supply Fan Drive Type Motor 7 Multi Speed Standard Motor 9 Multi Speed Oversized Motor Digit 16 Access 0 Standard Fork Access F Third Side Condenser Fork Acc...

Страница 7: ...Do not proceed with installation of a damaged unit without sales representative approval Inspect the complete exterior for signs of shipping damages to unit or packing material Verify that the nameplate data matches the sales order and bill of lading Verify that the unit is properly equipped and there are no material shortages Verify the power supply complies with the unit nameplate specifications...

Страница 8: ...and the module will automatically reset from a fault condition Discharge Line Thermostat Control The high pressure controls and the discharge line thermostat signals are wired in series and connected to the safety input of the LSD The compressor contactor coil is connected to the CC terminal of the LSD If the high pressure control switch or the discharge line thermostat is open the 24 Vac signal t...

Страница 9: ...enu OCC INPUT Attach the occupancy sensor to the OCC SENSOR wire and R terminal at customer connections The occupancy sensor must utilize a normally open contact for proper operation If an occupancy sensor is not used another option to controlling occupied and unoccupied status is to use the G input fan is running Connect the G input to the OCC SENSOR wire at customer connections The controller wi...

Страница 10: ...zer airflows or recirculation of hot condenser air Figure 1 Typical installation clearance for single and multiple unit applications NOTES 1 FOR HORIZONTAL DISCHARGE UNIT THIS MEASUREMENT IS REDUCED TO 1 6 TO MINIMIZE DUCT EXTENSION 2 WHEN EQUIPPED WITH ECONOMIZER OR BAROMETRIC RELIEF DAMPER CLEARANCE DISTANCE IS TO BE MEASURED FROM PROTRUDING HOOD INSTEAD OF BASE 3 CLEARANCE IS THE SAME IF ANY UN...

Страница 11: ...SWITCH ACCESS CONDENSATE DRAIN CONNECTION Figure 3 Cooling with optional electrical heat front and side views electric electric NOTES 1 THROUGH THE BASE ELECTRICAL IS NOT STANDARD ON ALL UNITS 2 VERIFY WEIGHT CONNECTION AND ALL DIMENSIONS WITH INSTALLER DOCUMENTS BEFORE INSTALLATION 13 7 15 16 4 1 2 22 7 16 39 13 16 58 5 8 58 5 8 59 5 16 123 1 8 50 7 8 Dimensional Data ...

Страница 12: ...ECTION AND ALL DIMENSIONS WITH INSTALLER DOCUMENTS BEFORE INSTALLATION THROUGH THE BASE ELECTRICAL RETURN SUPPLY 64 9 16 71 15 16 14 15 16 7 7 16 7 3 8 123 1 8 36 1 16 6 15 16 6 13 16 68 9 16 Figure 5 Cooling with optional electrical heat units back view horizontal configuration RETURN SUPPLY 46 11 16 25 11 16 26 15 16 82 1 16 20 3 16 6 6 5 1 2 Dimensional Data ...

Страница 13: ...4 1 16 357 MM 2 51 MM 69 1 2 1765 MM Figure 7 Cooling with optional electrical heat downflow duct connections field fabricated 1 25 4 MM CURB FLANGE LONG SIDES 14 1 16 357 MM 7 7 16 189 MM 73 7 16 1865 MM 1 25 MM 19 5 16 491 MM 1 25 MM 26 5 16 668 MM 1 25 MM 1 1 2 38 MM CURB FLANGE SHORT SIDES 66 1 2 1689 MM RETURN SUPPLY NOTES DUCT FLANGES MOUNT 7 7 16 DOWN INSIDE THE CURB ON THE 1 1 CURB FLANGES...

Страница 14: ...ling with optional electric heat barometric relief and economizer NOTES 1 VERIFY WEIGHT CONNECTION AND ALL DIMENSIONS WITH INSTALLER DOCUMENTS BEFORE INSTALLATION 2 BAROMETRIC RELIEF IS FOR USE WITH A DOWNFLOW ECONOMIZER ONLY BACK VIEW OF UNIT ECONOMIZER LEFT VIEW OF UNIT 123 1 8 5 15 16 20 3 16 18 5 16 20 5 8 FOR LOW LEAK 58 9 3 8 5 3 8 FOR LOW LEAK BAROMETRIC RELIFE FAN 68 3 8 86 15 16 7 3 4 13 ...

Страница 15: ...al electric heat manual damper NOTE VERIFY WEIGHT CONNECTION AND ALL DIMENSIONS WITH INSTALLER DOCUMENTS BEFORE INSTALLATION BACK VIEW OF UNIT LEFT VIEW OF UNIT FAN MANUAL DAMPER HOOD 123 1 8 18 1 4 26 7 8 24 7 8 12 13 16 86 15 16 Dimensional Data ...

Страница 16: ... supported continuously by a curb or equivalent frame support Table 2 Maximum unit and corner weights lb and center of gravity dimensions in Tons Unit Model No Weights lb a b Corner Weights c Center of Gravity in Shipping Net A B C D Length Width 15 GCC180A 2339 2013 649 508 398 459 55 37 17 5 GCC210A 2353 2028 653 511 399 464 55 37 20 GCC240A 2350 2025 643 512 403 466 55 37 25 GCC300A 2386 2061 6...

Страница 17: ...unit operating weights rigging before proceeding 1 Remove the shipping crate from around the unit Once fork trucking is complete and unit is ready to place on the curb remove all fork access brackets to drop the shipping boards from underneath the unit 4 brackets standard forking 6 brackets for 3 sided forking Do not remove the crating from the top of the unit 2 Rig the unit as shown in Figure 12 ...

Страница 18: ...equired anchor the unit to the roof with hold down bolts or isolators Check with a roofing contractor for proper waterproofing procedures Ductwork Elbows with turning vanes or splitters are recommended to minimize air noise due to turbulence and to reduce static pressure When attaching the ductwork to the unit provide a watertight flexible connector at the unit to prevent operating sounds from tra...

Страница 19: ...rovided in the unit This is a slip fit joint no threads Do not use PVC glue to connect condensate drain thread sealing compound or Teflon tape may be used A condensate trap must be installed at the unit due to the drain connection being on the negative pressure side of the fan A condensate drain line must be connected to the P Trap Pitch the drain lines at least 0 5 inch for every 10 feet of horiz...

Страница 20: ...omer connection diagram that is shipped with the unit for specific termination points The termination points depending on the customer option selected would be a factory mounted nonfused disconnect switch UDC Provide proper grounding for the unit in accordance with local and national codes Figure 13 Through the base electrical option ELECTRO MECHANICAL TBU FIELD WIRING ROUTE FIELD WIRING AS SHOWN ...

Страница 21: ...rical power to the unit must meet stringent requirements for the unit to operate properly Measure each leg phase to phase of the power supply Each reading must fall within the utilization range stamped on the unit nameplate If any of the readings do not fall within the proper tolerances notify the power company to correct this situation before operating the unit Excessive three phase voltage imbal...

Страница 22: ...e Electrical Components Failure to follow all electrical safety precautions when exposed to live electrical components could result in death or serious injury When it is necessary to work with live electrical components have a qualified licensed electrician or other individual who has been properly trained in handling live electrical components perform these tasks 4 Observe the ABC and CBA phase i...

Страница 23: ...NING Proper Field Wiring and Grounding Required Failure to follow code could result in death or serious injury All field wiring MUST be performed by qualified personnel Improperly installed and grounded field wiring poses FIRE and ELECTROCUTION hazards To avoid these hazards you MUST follow requirements for field wiring installation and grounding as described in NEC and your local state national e...

Страница 24: ...24 RT SVX50M EN Figure 15 Field wiring route Installation ...

Страница 25: ...0 using the setpoint potentiometer located on the Economizer Control ECA if applicable Electromechanical Controls Test Procedure See unit schematic for correct wire numbers Fan Test and Minimum Ventilation Connect red thermostat wire R to black thermostat wire G Economizer Cooling Connect a jumper wire across OAT on Economizer Control ECA Connect red thermostat R wire to yellow thermostat wire Y1 ...

Страница 26: ...tentiometer settings Potentiometer Setting Dry Bulb Enthalpy A 27 Btu lb 63 kJ kg 73 F 22 8 C B 25 Btu lb 58 kJ kg 70 F 21 1 C Table 4 Potentiometer settings continued Potentiometer Setting Dry Bulb Enthalpy C a 23 Btu lb 53 kJ kg 67 F 19 4 C D 22 Btu lb 51 kJ kg 63 F 17 2 C E 19 Btu lb 44 kJ kg 55 F 12 8 C a Factory setting Cooling with an Economizer Standard Economizer The economizer is utilized...

Страница 27: ... Fan Only Cool 1 or Economizer Only and the indoor fan is at low speed the unit will not be bringing in as much fresh air as normal By setting a higher minimum damper position this problem could be solved but that would mean more fresh air than may be desired when the supply fan is at high speed To overcome these situations the control will require the setting of two economizer minimum positions t...

Страница 28: ...is enabled b With stage 3 delay STG3 DLY in Advanced setup menu can turn on 2nd stage of mechanical cooling Y2 O after the delay if the call for Y1 I and Y2 I have not been satisfied Table 6 Dry bulb operation with DCV CO2 sensor 2 speed fan DCV OA Good to economize Y1 I Y2 I FAN SPD Y1 O Y2 O Occupied Unoccupied Below set No Off Off Low 0 v Off 0 v Off VENTMIN L Closed On Off Low 24 v On 0 v Off ...

Страница 29: ...n 0 v Off VENTMIN L to VENTMAX Closed On On High 24 v On 24 v On VENTMIN H to VENTMAX Closed Yes Off Off Low 0 v Off 0 v Off VENTMIN L to VENTMAX Closed On Off Low 0 v Off 0 v Off VENTMIN L to Full Open Closed to Full Open On On High DELAY 24 v On b 0 v Off a VENTMIN H to Full Open Closed to Full Open a With stage 3 delay STG3 DLY in Advanced setup menu can turn on 2nd stage of mechanical cooling ...

Страница 30: ...d to protect compressors from reverse rotation It has an operating input voltage range of 180 600 Vac and LED indicators for ON and FAULT There are no field adjustments and the module will automatically reset from a fault condition Low Pressure Cutout The low pressure cutouts are wired in series with the high pressure cutouts and the temperature discharge limits If this circuit is open before a co...

Страница 31: ...oller module begins a 5 minute power up delay before enabling mechanical cooling Compressor Start Up 1 Attach a set of service gauges onto the suction and discharge gauge ports for each circuit Refer to the refrigerant circuit illustration in the Service Facts See Cooling Operation p 27 for startup instructions Scroll Compressors a Once each compressor has started verify that the rotation is corre...

Страница 32: ...utlined in the previous sections i e operating the unit in each of its modes through all available stages of cooling and heating perform these final checks before leaving the unit Program the Night Setback NSB panel if applicable for proper unoccupied operation Refer to the programming instructions for the specific panel Verify that the Remote panel System selection switch Fan selection switch and...

Страница 33: ...proper belt tension 2 Set the large O ring on the belt tension gauge at the deflection value determined in Step 1b 3 Set the small O ring at zero on the force scale of the gauge plunger 4 Place the large end of the gauge at the center of the belt span then depress the gauge plunger until the large O ring is even with the top of the next belt or even with a straightedge placed across the fan and mo...

Страница 34: ...ans to ensure free movement and check motor bearings for wear Verify that all of the fan mounting hardware is tight Inspect the F A R A damper hinges and pins to ensure that all moving parts are securely mounted Keep the blades clean as necessary WARNING Rotating Components Failure to disconnect power before servicing could result in rotating components cutting and slashing technician which could ...

Страница 35: ... cleaning agents can be either acidic or highly alkaline and can burn severely if contact with skin or eyes occurs Handle chemical carefully and avoid contact with skin ALWAYS wear Personal Protective Equipment PPE including goggles or face shield chemical resistant gloves boots apron or suit as required For personal safety refer to the cleaning agent manufacturer s Materials Safety Data Sheet and...

Страница 36: ...36 RT SVX50M EN Table 14 Unit data log continued schematic s connections Network ID Maintenance ...

Страница 37: ...Psig kPa Liquid Press Psig kPa Superheat F C Sub cool F C Compr Oil Level Suct Press Psig kPa Disch Press Psig kPa Liquid Press Psig kPa Superheat F C Sub cool F C ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low ok low Maintenance ...

Страница 38: ...g 1 The economizer controller provides alarm messages that display on the 2 line LCD If one or more alarms are present and there has been no keypad activity for at least 5 minutes the Alarms menu displays and cycles through the active alarms Note Note You can also navigate to the Alarms menu at any time 2 Once the alarm has been identified and the cause has been removed for example replaced faulty...

Страница 39: ... space turn the Mode selection switch at the thermostat to the Off position After approximately 30 seconds turn the Mode selection switch to the desired mode i e Heat Cool or Auto Method 2 To reset the system at the unit cycle the unit power by turning the disconnect switch Off and then On Condensate Overflow Switch When the condensate overflow switch is closed a drain pan overflow condition is in...

Страница 40: ...or by contacting technical support Table 17 Wiring diagrams Type of Airflow Schematic Type Voltage Diagram Number Description Multi Speed Fans Power 208 575 1213 4574 Schematic PWR EM Cooling only with VFD 15T 25T Control 208 575 1213 4571 ECC180 300 60Hz Cooling only Electric Heat w VFD All Device Location 208 575 1213 4601 ECC180 300 60Hz VFD Electric Heat ...

Страница 41: ...s and liabilities under this warranty are limited to furnishing F O B factory or warehouse at the warrantor designated shipping point freight allowed to Buyer s city or port of export for shipments outside the conterminous United States a replacement product or at the option of the warrantor parts for the repair of the product not conforming to this warranty and which have been returned to the war...

Страница 42: ...42 RT SVX50M EN Notes ...

Страница 43: ...RT SVX50M EN 43 Notes ...

Страница 44: ... please visit trane com or americanstandardair com Trane and American Standard have a policy of continuous product and product data improvement and reserve the right to change design and specifications without notice We are committed to using environmentally conscious print practices RT SVX50M EN 03 Dec 2022 Supersedes RT SVX50L EN April 2022 2022 ...

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