background image

284806-YIM-A-0107

58

Unitary Products Group

FIGURE 24 - UNIT CONTROL BOARD

TABLE 29: UNIT CONTROL BOARD FLASH CODES

FLASH CODE

DESCRIPTION

GREEN

LED

16

RED

LED

8

RED

LED

4

RED

LED

2

RED

LED

1

On Steady

This is a Control Failure

-

-

-

-

-

1 Flash

Not Applicable

-

-

-

-

-

2 Flashes

Control waiting ASCD

1

1.

Non-alarm condition.

Flashing

Off

Off

On

Off

3 Flashes

HPS1 Compressor Lockout

Off

Off

Off

On

On

4 Flashes

HPS2 Compressor Lockout

Off

Off

On

Off

Off

5 Flashes

LPS1 Compressor Lockout

Off

Off

On

Off

On

6 Flashes

LPS2 Compressor Lockout

Off

Off

On

On

Off

7 Flashes

FS1 Compressor Lockout

Off

Off

On

On

On

8 Flashes

FS2 Compressor Lockout

Off

On

Off

Off

Off

9 Flashes

Ignition Control Locked Out / Ignition Control Failure

Off

On

Off

Off

On

10 Flashes

Compressors Locked Out on Low Outdoor Air Temperature

1

Flashing

On

Off

On

Off

11 Flashes

Compressors locked out because the Economizer is using free 

Cooling

1

Flashing

On

Off

On

On

12 Flashes

Unit Locked Out due to Fan Overload Switch Failure

Off

On

On

Off

Off

13 Flashes

Compressor Held Off due to Low Voltage

1

Flashing

On

On

Off

On

14 Flashes

EEPROM Storage Failure

Off

On

On

On

Off

OFF

No Power or Control Failure

Off

Off

Off

Off

Off

Check

Alarm

History

Reset All

ASCDs for
One Cycle

Non Alarm

Condition Green

LED Flashing

Current Alarm

Flashed

Red LED

Summary of Contents for DM 240

Page 1: ...TURE 6 INSTALLATION 7 OPERATION 41 START UP COOLING 47 START UP GAS HEAT 48 TROUBLESHOOTING 50 See the following pages for a complete Table of Contents NOTES CAUTIONS AND WARNINGS The installer should pay particular attention to the words NOTE CAUTION and WARNING Notes are intended to clarify or make the installation easier Cautions are given to prevent equipment damage Warnings are given to alert...

Page 2: ... OF OPERATIONS OVERVIEW 41 COOLING SEQUENCE OF OPERATION 41 CONTINUOUS BLOWER 41 INTERMITTENT BLOWER 41 VAV BLOWER OPERATION 41 NO OUTDOOR AIR OPTIONS 41 ECONOMIZER WITH SINGLE ENTHALPY SENSOR 41 ECONOMIZER WITH DUAL ENTHALPY SENSORS 42 ECONOMIZER SINGLE OR DUAL WITH POWER EXHAUST 42 MOTORIZED OUTDOOR AIR DAMPERS 42 COOLING OPERATION ERRORS 42 HIGH PRESSURE LIMIT SWITCH 42 LOW PRESSURE LIMIT SWITC...

Page 3: ... 22 7 PHYSICAL DATA 23 8 SUPPLY FAN VFD WEIGHTS IN LBS 23 9 DM 180 240 ELECTRICAL DATA WITHOUT POWERED CONVENIENCE OUTLET 24 10 DM 300 ELECTRICAL DATA STANDARD MOTOR WITHOUT POWERED CONVENIENCE OUTLET 25 11 DM 300 ELECTRICAL DATA HIGH STATIC MOTOR WITHOUT POWERED CONVENIENCE OUTLET 25 12 DM 180 240 ELECTRICAL DATA WITH POWERED CONVENIENCE OUTLET 26 13 DM 300 ELECTRICAL DATA STANDARD MOTOR WITH POW...

Page 4: ...ld install repair main tain or service this equipment Observe all precautions in the literature on labels and tags accompanying the equipment whenever working on air conditioning equipment Be sure to follow all other safety precautions that apply Wear safety glasses and work gloves and follow all safety codes Use a quenching cloth and have a fire extinguisher available for all brazing operations I...

Page 5: ...ar attention to the words NOTE CAUTION and WARNING Notes are intended to clarify or make the installation easier Cau tions are given to prevent equipment damage Warn ings are given to alert installer that personal injury and or equipment damage may result if installation proce dure is not handled properly THIS PRODUCT MUST BE INSTALLED IN STRICT COMPLIANCE WITH THE ENCLOSED INSTALLATION INSTRUC TI...

Page 6: ...roller DFS APS Honeywell Controller DFS APS Novar Controller DFS APS Simplicity IntelliComfort Controller Simplicity IntelliComfort Controller w ModLinc Hot Gas Bypass Standard on VAV Optional on CV Variable Air Volume VFD Not Available with Factory Installed BAS Options Variable Air Volume VFD With Manual Bypass Not Available with Factory Installed BAS Options Variable Air Volume VFD Ready for Cu...

Page 7: ...in accordance with the following national and local safety codes In U S A National Electrical Code ANSI NFPA No 70 National Fuel Gas Code Z223 1 Gas Fired Central Furnace Standard ANSI Z21 47a Local gas utility requirements In Canada Current Canadian Electrical Code C22 1 Current Gas Installation Codes CSA B149 1 Local plumbing and waste water codes Other applicable local codes Refer to the Unit A...

Page 8: ...ed on a roof curb or special frame other than a YORK roof curb gasketing must be applied to all surfaces that come in contact with the unit underside TABLE 1 UNIT APPLICATION DATA UNIT MODEL NUMBER DM180 DM240 DM300 Voltage Variation Min Max 1 208 230 3 60 187 253 460 3 60 414 506 575 3 60 518 630 Supply Air CFM Min Max 4 500 7 200 6 000 9 400 7 500 12 500 Wet Bulb Temperature ºF of Air on Evapora...

Page 9: ...sions for ade quate combustion and ventilation air in accordance with Section 5 3 Air for Combustion and Ventilation of the National Fuel Gas Code ANSI Z223 1 in U S A or Sections 7 2 7 3 or 7 4 of Gas Installation Codes CSA B149 1 in Canada and or applicable provisions of the local building codes Refer to Figures 13 14 and 15 for the dimensions and clearances required for com bustible constructio...

Page 10: ... surfaces on the hood prior to installing the hood Extend gasketing 1 4 inch beyond the top and bottom of the two side flanges to insure adequate sealing Adjusting the damper to the desired air flow may be done before mounting the hood into position or after installation by removing the front hood panel or the screen on the bottom of the hood Damper baffle in position 1 will allow approximately 10...

Page 11: ... kept clean or replaced with same size and type Dirty filters will reduce the capacity of the unit and will result in frosted coils or safety shut down Minimum filter area and required sizes are shown in Physical Data Table 7 SERVICE ACCESS The following removable panels provide access to all serviceable components Compressor compartment Electric Heat compartment Gas Heat compartment Two panels Si...

Page 12: ... 7 0 0 1 0 0 2 4 i n c l u d e s s u b b a s e 2 T e r m i n a l s A 1 a n d A 2 p r o v i d e a r e l a y o u tp u t to c l o s e th e o u td o o r e c o n o m i z e r d a m p e r s w h e n th e th e r m o s ta t s w i tc h e s to th e s e t b a c k p o s i ti o n 2 4 V o l t T r a n s fo r m e r 2 T O R E M O T E S E N S O R 2 E T 0 4 7 0 1 3 2 4 IF U S E D O C C W 1 W 2 Y 1 G Y 2 X R S D C R E ...

Page 13: ...er cir cuits Wire entry at knockout openings require conduit fittings to comply with NEC in U S A CEC in Can ada and or local codes Refer to Figure 13 for installa tion location If any of the wire supplied with the unit must be replaced replacement wire must be of the type shown on the wiring diagram and the same mini mum gauge as the replaced wire Electrical line must be sized properly to carry t...

Page 14: ...piping All units require a one inch pipe connection at the entrance fitting Maximum capacity of pipe in cubic feet of gas per hour Based upon a pressure drop of 0 3 inch water column and 0 6 specific gravity gas TABLE 3 ELECTRIC HEAT APPLICATION DATA NOMINAL HEATER SIZE KW VOLTAGE 3 PHASE 60 HZ MINIMUM CFM UNIT SIZE 15 TON 20 TON 25 TON 18 208 230 460 575 4500 6000 7500 36 208 230 460 575 4500 54 ...

Page 15: ...to the unit have been purged of air 5 The gas supply should be a separate line and installed in accordance with all safety codes as prescribed under Limitations After the gas con nections have been completed open the main shut off valve admitting normal gas pressure to the mains Check all joints for leaks with soap solution or other material suitable for the purpose NEVER USE A FLAME 6 The furnace...

Page 16: ...ipe siz ing is available from most regulator manufacturers and L P propane gas suppliers L P propane gas is an excellent solvent and special pipe compound must be used when assembling piping for this gas as it will quickly dissolve white lead or most standard commercial compounds Shellac base com pounds such as Rectorseal 5 are satisfactory for this type of gas Check all connections for leaks when...

Page 17: ...an be found in the kit The exhaust fan all supporting brackets angles and the wiring are factory installed as part of the power exhaust option OPTIONAL ECONOMIZER AND POWER EXHAUST DAMPER SET POINT ADJUSTMENTS AND INFORMA TION Remove the economizer access panel from the unit Loosen but do not remove the two panel latches Locate the economizer control module where the fol lowing adjustments will be...

Page 18: ...ess panel OPTIONAL VARIABLE AIR VOLUME VAV A variable air volume VAV option using a variable fre quency drive VFD is available for applications requir ing a constant supply duct static pressure A differential pressure transducer is used to monitor supply duct static pressure and return a speed reference signal to the VFD to control the output of the indoor blower motor DUCT STATIC PRESSURE TRANSDU...

Page 19: ...building s VAV boxes to ensure a fully open damper during heating operation MANUAL BYPASS An optional factory installed manual bypass switch available with factory installed VFD can be found in the Blower Motor Access compartment and has the follow ing three positions DRIVE routes power through the VFD for modu lating control of the indoor blower motor LINE or BYPASS routes power directly to the m...

Page 20: ... utilize the unit s mounting bracket the maximum rec ommended drive dimensions are as follows For 5 hp motor applications 10 H x 6 W x 7 D For 7 5 thru 15 hp motor applications 13 H x 8 W x 8 D If the drive will not fit in the allotted space then it will have to be mounted within a NEMA 4 enclosure for outside installation or elsewhere within the building on a perpendicular wall which is not subje...

Page 21: ...D C C B B A A CONTROL CURVE CONTROL POINT APPROX 0 F 0 C AT 50 RH A D C B 63 17 73 23 70 21 67 19 FIGURE 10 HONEYWELL ECONOMIZER CONTROL W7212 N1 N P1 P EXH Set EXH Min Pos IAQ Max IAQ IAQ Min Free Cool T T1 AQ1 AQ SO SO SR SR A B C D TR TR1 24 Vac HOT 24 Vac COM EF EF1 2 3 4 5 1 Exhaust Air Adjustment Screw Exhaust Air LED Damper Min Position Screw Indoor Air Quality Max Adjustment Screw Indoor A...

Page 22: ...8 563 715 684 300 Gas 2531 593 645 674 619 180 Elec 2100 492 514 558 536 240 Elec 2300 295 517 658 630 300 Elec 2331 546 594 621 570 Unit Size Total Shipping Weight 6 Point Loads lbs A B C D E F 180 Gas 2300 351 367 392 416 399 375 240 Gas 2500 334 350 426 502 481 407 300 Gas 2531 390 412 436 456 430 407 180 Elec 2100 320 335 358 380 364 343 240 Elec 2300 307 322 392 462 442 375 300 Elec 2331 359 ...

Page 23: ...or 4 4 4 QUANTITY PER UNIT 18 X 24 X 2 or 4 5 TOTAL FACE AREA Sq Ft 15 20 24 CHARGE REFRIGERANT 22 Lb Oz SYSTEM No 1 17 8 18 0 18 0 SYSTEM No 2 8 8 18 0 18 0 OPERATING WEIGHTS LBS BASIC UNIT COOLING ONLY 1900 2100 2291 GAS ELECTRIC N24 2100 2300 2491 N32 2140 2340 2531 OPTIONS ECONOMIZER 160 ECONOMIZER WITH POWER EXHAUST 245 MOTORIZED DAMPER 150 ELECTRIC HEATER 18 KW 25 36 KW 30 54 KW 35 72 KW 40 ...

Page 24: ... 6 62 2 2 7 0 0 0 None 0 0 42 6 50 E18 18 0 1 21 7 42 6 50 E36 36 0 2 43 3 62 9 70 E54 54 0 2 65 0 73 7 90 E72 72 0 2 86 6 95 4 110 575 7 7 50 1 7 5 3 0 0 None 0 0 33 7 40 E18 18 0 1 17 3 33 7 40 E36 36 0 2 34 6 49 9 50 E54 54 0 2 52 0 58 6 70 E72 72 0 2 69 3 75 9 90 240 20 208 19 2 124 4 5 19 6 0 0 None 0 0 110 3 125 E18 13 5 1 37 5 110 3 125 E36 27 0 2 75 1 118 2 125 E54 40 6 2 112 6 165 4 175 E...

Page 25: ... 102 9 110 575 17 3 102 1 7 10 0 0 0 None 52 3 60 E18 18 0 1 17 3 52 3 60 E36 36 0 2 34 6 55 8 60 E54 54 0 2 52 0 64 5 70 E72 72 0 2 69 3 81 8 90 TABLE 11 DM 300 ELECTRICAL DATA HIGH STATIC MOTOR WITHOUT POWERED CONVENIENCE OUTLET MODEL TON NAGE VOLTAGE COMPRESSORS OD FAN MOTORS FLA EACH ID BLOWER MOTOR FLA CONV OUTLET AMPS HEATER OPTION MIN CIRCUIT AMPACITY AMPS MAX FUSE BRKR1 SIZE AMPS RLA EACH ...

Page 26: ... 62 2 2 7 0 5 0 None 0 0 47 6 50 E18 18 0 1 21 7 47 6 50 E36 36 0 2 43 3 69 1 70 E54 54 0 2 65 0 80 0 90 E72 72 0 2 86 6 101 6 110 575 7 7 50 1 7 5 3 4 0 None 0 0 37 7 45 E18 18 0 1 17 3 37 7 45 E36 36 0 2 34 6 54 9 60 E54 54 0 2 52 0 63 6 70 E72 72 0 2 69 3 80 9 90 240 20 208 19 2 124 4 5 19 6 10 0 None 0 0 120 3 125 E18 13 5 1 37 5 120 3 125 E36 27 0 2 75 1 130 7 150 E54 40 6 2 112 6 177 9 200 E...

Page 27: ... 109 1 110 575 17 3 102 1 7 10 0 4 0 None 56 3 70 E18 18 0 1 17 3 56 3 70 E36 36 0 2 34 6 60 8 70 E54 54 0 2 52 0 69 5 70 E72 72 0 2 69 3 86 8 90 TABLE 14 DM 300 ELECTRICAL DATA HIGH STATIC MOTOR WITH POWERED CONVENIENCE OUTLET MODEL TON NAGE VOLTAGE COMPRESSORS OD FAN MOTORS FLA EACH ID BLOWER MOTOR FLA CONV OUTLET AMPS HEATER OPTION MIN CIRCUIT AMPACITY AMPS MAX FUSE BRKR1 SIZE AMPS RLA EACH LRA...

Page 28: ...NIT BASE WITH RAILS Shown separately to illustrate Bottom Duct openings Power and Gas Piping Connection locations 12 1 2 9 1 4 8 1 8 9 3 4 3 3 4 B POWER WIRING ENTRY A CONTROL WIRING ENTRY 92 CONDENSER COILS COIL GUARD COMPRESSOR ACCESS ECONOMIZER MOTORIZED DAMPER FIXED OUTDOOR INTAKE AIR AND POWER EXHAUST RAIN HOODS See detail Y FIELD SUPPLIED DISCONNECT SWITCH LOCATION BLOWER COMPARTMENT ACCESS ...

Page 29: ...on The covering consists of a heavy black paper composition 3 Replace the side supply and return air compartment panels For side duct applications 1 Replace the side panels on the supply and return air compartments with the side duct flange accessory kit panels 2 Connect ductwork to the flanges on those panels SUPPLY AIR RETURN AIR OUTDOOR AIR 5 1 8 18 5 8 27 3 4 28 5 8 15 TON 39 5 8 20 25 TON 40 ...

Page 30: ...NCE LOCATION CLEARANCE Front 36 Rear 24 Less Economizer 49 With Economizer Left Side Filter Access 24 Less Economizer 36 With Economizer 3 Right Side Cond Coil 36 Below Unit1 1 Units may be installed on combustible floors made from wood or class A B or C roof covering material 0 Above Unit2 2 Units must be installed outdoors Overhanging structures or shrubs should not obstruct condenser air discha...

Page 31: ...static pressure and BHP Since no temperature data is given we will assume an air temperature of 70 F Table 15 shows the correction factor to be 0 832 Corrected static pressure 1 5 x 0 832 1 248 IWC Corrected BHP 4 0 x 0 832 3 328 Example 2 A system located at 5 000 feet of elevation is to deliver 6 000 CFM at a static pressure of 1 5 Use the unit blower tables to select the blower speed and the BH...

Page 32: ...284806 YIM A 0107 32 Unitary Products Group FIGURE 16 ALTITUDE TEMPERATURE CONVERSION FACTOR ...

Page 33: ... 9 5 2 4 7 0 7 5 7 5 1 208 VOLT AND HIGH SPEED DRIVE 965 6 0 1 2 2 9 2 6 1 0 3 6 3 2 0 8 4 0 3 6 0 5 4 7 4 2 0 4 5 0 4 4 980 5 5 1 3 3 0 2 7 1 1 3 7 3 3 0 9 4 1 3 7 0 6 4 8 4 3 0 5 5 1 4 6 1025 4 5 1 5 3 2 2 9 1 3 3 9 3 5 1 1 4 5 4 0 0 8 5 1 4 6 0 7 5 6 5 0 1065 3 5 1 6 3 4 3 0 1 4 4 0 3 6 1 2 4 7 4 2 1 0 5 5 4 9 1095 3 0 1 7 3 5 3 1 1 5 4 2 3 8 1 3 4 9 4 4 1 2 5 7 5 1 1130 2 0 1 9 3 7 3 3 1 7 4 5...

Page 34: ...2 6 3 5 3 0 7 6 9 5 8 0 2 7 3 6 1 1010 4 0 1 8 5 8 4 9 1 7 6 3 5 3 1 5 6 9 5 8 1 0 7 5 6 3 0 5 7 9 6 7 1020 3 5 1 9 6 1 5 1 1 8 6 5 5 5 1 6 7 1 6 0 1 1 7 8 6 6 0 6 8 3 7 0 1035 3 0 2 0 6 2 5 2 1 9 6 8 5 7 1 7 7 4 6 2 1 2 8 1 6 8 0 7 8 6 7 3 1050 2 5 2 1 6 4 5 4 2 0 7 0 5 9 1 8 7 6 6 4 1 3 8 3 7 0 1075 2 0 2 3 6 6 5 5 2 1 7 2 6 0 1 9 7 8 6 6 1 5 8 6 7 2 1100 1 0 2 4 6 7 5 6 2 2 7 3 6 1 2 1 7 9 6 7 ...

Page 35: ...4 1 0 4 4 3 9 0 8 5 0 4 5 0 6 5 6 5 0 208 VOLT AND HIGH SPEED DRIVE 965 6 0 1 2 2 7 2 5 0 9 3 2 2 9 0 6 3 7 3 3 0 4 4 4 3 9 0 2 5 0 4 5 980 5 5 1 3 2 9 2 6 1 0 3 4 3 0 0 7 3 8 3 4 0 5 4 5 4 0 0 3 5 1 4 6 1025 4 5 1 4 3 1 2 8 1 2 3 6 3 2 0 9 4 1 3 7 0 7 4 8 4 3 0 4 5 5 4 9 1065 3 5 1 6 3 4 3 0 1 4 3 9 3 5 1 1 4 5 4 0 0 9 5 1 4 6 1125 2 0 1 9 3 6 3 2 1 7 4 4 3 9 1 4 5 0 4 5 1 2 5 8 5 2 1170 1 0 2 1 ...

Page 36: ...5 0 1 9 4 5 3 8 1 5 5 4 4 5 1 0 6 3 5 3 0 4 7 2 6 1 0 1 8 5 7 1 995 4 5 2 1 4 5 3 9 1 6 5 5 4 7 1 1 6 4 5 4 0 5 7 5 6 3 0 2 8 6 7 3 1025 3 5 2 3 4 9 4 1 1 8 5 8 4 9 1 3 6 7 5 7 0 7 8 0 6 7 1050 2 5 2 5 5 1 4 3 2 0 6 1 5 1 1 4 7 1 6 0 0 9 8 4 7 0 1065 2 0 2 6 5 3 4 4 2 1 6 3 5 3 1 5 7 3 6 2 1 0 8 6 7 2 1100 1 0 2 9 5 6 4 7 2 3 6 8 5 7 1 8 7 9 6 6 230 460 575 VOLT AND STANDARD DRIVE 870 6 0 1 3 3 6 ...

Page 37: ...2 1215 4 0 2 7 8 6 7 0 2 1 10 4 8 5 1 4 12 3 10 1 0 6 14 3 11 7 1255 3 0 3 0 9 1 7 4 2 4 11 0 9 0 1 7 12 9 10 6 0 9 15 0 12 3 1290 2 0 3 2 9 5 7 8 2 7 11 5 9 4 2 0 13 5 11 1 1 2 15 6 12 8 1330 1 0 3 5 10 0 8 2 3 0 12 0 9 9 2 3 14 1 11 6 1 5 16 4 13 4 1365 0 0 3 7 10 5 8 6 3 2 12 6 10 3 2 6 14 7 12 1 1 8 17 0 13 9 230 460 575 VOLT AND STANDARD DRIVE 975 6 0 1 4 5 9 4 9 1 0 7 3 6 0 0 5 8 8 7 2 1005 ...

Page 38: ...E OF RETURN DUCTWORK IWG 0 2 0 3 0 4 0 5 0 6 CFM KW CFM KW CFM KW CFM KW CFM KW HIGH 5250 0 83 4500 0 85 4200 0 88 3750 0 93 3000 0 99 MEDIUM 4900 0 77 3900 0 79 3500 0 82 2900 0 85 LOW 4400 0 72 3700 0 74 3000 0 78 TABLE 23 BLOWER MOTOR AND DRIVE DATA MODEL SIZE DRIVE BLOWER RANGE RPM MOTOR1 ADJUSTABLE MOTOR PULLEY FIXED BLOWER PULLEY BELT NOTCHED HP FRAME EFF DESIG NATION OUTSIDE DIA IN PITCH DI...

Page 39: ... the supply air blower and the motor pulley adjustment turns open can be determined from the Blower Per formance Data Tables High speed drive accessories containing a smaller blower pulley and a shorter belt are available for appli cations requiring the supply air blower to produce higher CFM s and or higher static pressures Use Model 1LD0416 for 15 ton units Model 1LD0417 for 20 ton units and Mod...

Page 40: ... evaporator coil may vary greatly measuring the pressure drop across a wet coil under field conditions would be inaccurate To assure a dry coil the compressors should be deac tivated while the test is being run 4 Knowing the pressure drop across a dry coil the actual CFM through the unit can be determined from the curve in Pressure Drop vs Supply Air CFM Figure 18 After readings have been obtained...

Page 41: ...NO OUTDOOR AIR OPTIONS When the thermostat calls for the first stage of cooling the low voltage control circuit from R to Y1 and G is completed For first stage cooling compressor 1 condenser fan motor 1 and condenser fan motor 2 for 15 and 20T only if the ambient temperature is above 60ºF are energized After completing the spec ified fan on delay for cooling the UCB will energize the blower motor ...

Page 42: ...vides minimum position but does not provide power exhaust operation MOTORIZED OUTDOOR AIR DAMPERS This system operation is the same as the units with no outdoor air options with one exception When the R to G circuit is complete the motorized damper drives open to a position set by the thumbwheel on the damper motor When the R to G circuit is opened the damper spring returns fully closed COOLING OP...

Page 43: ... switch to protect against exces sive discharge pressures due to a blocked con denser coil or a condenser motor failure opens at 380 10 psig and resets at 300 10 psig 3 A low pressure switch to protect against loss of refrigerant charge opens at 22 5 psig and resets at 45 5 psig The above pressure switches are hard soldered to the unit The refrigeration systems are independently mon itored and con...

Page 44: ...ardless of unit operation sta tus i e the limit is monitored at all times If the temperature limit opens three times within one hour it will lock on the indoor blower motor and a flash code is initiated See Table 29 SAFETY CONTROLS The unit control board monitors the temperature limit switch of electric heat units The control circuit includes the following safety con trols 1 Temperature Limit Swit...

Page 45: ...is not detected then IC1 will lock out first stage furnace operation for five minutes or until 24V power is removed from the module either at the unit or by resetting the room thermostat When the thermostat calls for the second stage of heating the low voltage control circuit from R to W2 is completed thru the UCB Heat relay RW2 is ener gized The RW2 1 contact is closed energizing the second stage...

Page 46: ... will de energize the indoor blower follow ing the elapse of the fan off delay for heating If voltage has been sensed at the GV for at least 15 seconds during the fan on delay for heating and GV voltage or W1 is lost the indoor blower is forced on for the length of the fan off delay for heating SAFETY CONTROLS The unit control board monitors the temperature limit switch and the gas valve of gas fu...

Page 47: ...lt in longer heat cycles and a greater temperature swing in the conditioned space Reducing the value below the correct setpoint will give shorter ON cycles and may result in the low ering of the temperature within the conditioned space START UP COOLING PRESTART CHECK LIST After installation has been completed 1 Check the electrical supply voltage being supplied Be sure that it is the same as liste...

Page 48: ... above room tem perature pilot burner ignition will occur and after an interval to prove pilot flame main burners will ignite TO SHUT DOWN 1 Turn off electric power to unit 2 Depress knob of gas valve while turning to off position or turn gas valve switch to off position POST START CHECK LIST GAS After the entire control circuit has been energized and the heating section is operating make the foll...

Page 49: ...WER TO THE UNIT 1 Remove the screws holding either end of the mani fold to the burner supports 2 Open the union fitting in the gas supply line just upstream of the unit gas valve and downstream from the main manual shut off valve 3 Remove the gas piping closure panel 4 Disconnect wiring to the gas valves and spark igni tors Remove the manifold burner gas valve assembly by lifting up and pulling ba...

Page 50: ...e Take readings of both the return air and the heated air in the ducts about six feet from the furnace where they will not be affected by radiant heat Increase the blower cfm to decrease the temper ature rise decrease the blower cfm to increase the rise Refer to the Blower Motor and Drive Data Table 23 BELT DRIVE BLOWER All units have belt drive single speed blower motors The variable pitch pulley...

Page 51: ... wiring between the UCB and M3 8 If 24 volts is not present at the FAN terminal check for 24 volts from the room thermostat If 24 volts are not present from the room thermostat check for the following a proper operation of the room thermostat contact between R and G with the fan switch in the ON posi tion and in the AUTO position during operation calls b proper wiring between the room thermostat a...

Page 52: ...lts at the Y1 ECON terminal If 24 volts is not present check for loose wiring from the Y1 OUT terminal to the Mate N Lock plug the jumper in the Mate N Lock plug and in the wiring from the Mate N Lock plug to the Y1 ECON terminal 13 For units with economizers If 24 volts is present at the Y1 OUT terminal check for 24 volts at the Y1 ECON terminal If 24 volts is not present check for loose wiring f...

Page 53: ...have opened the UCB may have locked out the compressor for repeat trips The UCB should be flashing a code If not press and release the ALARMS button on the UCB The UCB will flash the last five alarms on the LED If the compressor is locked out remove any call for cooling at the thermostat or by disconnect ing the thermostat wiring at the Y2 UCB terminal This will reset any compressor lock outs NOTE...

Page 54: ...he next step 10 If 24 volts is present at the UCB Y1 terminal and none of the switches are open and the compressor is not locked out the UCB may have the compres sor in an ASCD Check the LED for an indication of an ASCD cycle The ASCD should time out within 5 minutes Press and release the TEST button to reset all ASCDs 11 If 24 volts is present at the UCB Y1 terminal and the compressor is not out ...

Page 55: ... Failing the above if there is line voltage supplied at M3 M3 is pulled in and the supply air blower motor still does not operate replace the motor For units with VFD if there is line voltage supplied at M3 M3 is pulled in and the blower motor does not operate check all power control wiring con nections to and from the drive and for any fault warning messages displayed on the drive s digital displ...

Page 56: ...ermo stat to the relay board If all connections are cor rect replace the relay board The draft motor runs but the furnace does not light and the sparker does not spark 1 The ignition control IC1 IC2 may be locked out due to either a flame roll out or 100 shut off These safety features are described above If lock out has occurred 24V must be removed from the ignition controls This is done at the un...

Page 57: ... ignitor control and the gas valve If intact check for 24 volts across terminals MV and COMMON termi nals If no voltage detected replace ignitor control If voltage is present replace gas valve Furnace lights with roll out or one burner has delayed ignition 1 Make sure that the pilot burner is aligned properly with the carryover as described in PILOT CHECK OUT Page 49 2 Make sure that the carryover...

Page 58: ...hes FS1 Compressor Lockout Off Off On On On 8 Flashes FS2 Compressor Lockout Off On Off Off Off 9 Flashes Ignition Control Locked Out Ignition Control Failure Off On Off Off On 10 Flashes Compressors Locked Out on Low Outdoor Air Temperature1 Flashing On Off On Off 11 Flashes Compressors locked out because the Economizer is using free Cooling1 Flashing On Off On On 12 Flashes Unit Locked Out due t...

Page 59: ...least 2 seconds The green status LED Option Byte will be turned on and the red status LED Heat Delay is turned off Press the COMM SETUP SELECT button to tog gle into the Heat Delay Setup the green LED will turn off and the red LED for Heat Delay will turn on The 8 4 2 and 1 LEDs will then show the status of the Heat Delay See Table 30 Press the UP or Down button to change the LED status to corre s...

Page 60: ...ct to change without notice Printed in U S A 284806 YIM A 0107 Copyright 2007 by Unitary Products Group All rights reserved Supersedes 175233 YIM A 0706 Unitary 5005 Norman Products York OK Group Drive 73069 ...

Reviews: