Lennox ML193UH045P36B Unit Information
  1. Manuals
  2. Brands
  3. Lennox Manuals
  4. Furnace
  5. ML193UH045P36B
  6. Unit information
Lennox ML193UH045P36B Unit Information

Lennox ML193UH045P36B Unit Information

Ml193uh series
Hide thumbs Also See for ML193UH045P36B:
Table of Contents

Advertisement

Quick Links

Service Literature
ML193UH series units are high-efficiency gas furnaces
manufactured with Lennox DuralokPlust aluminized steel
clamshell-type heat exchangers, with a stainless steel con­
densing coil. ML193UH units are available in heating input
capacities of 44,000 to 132,000 Btuh (13 to 38.6 kW) and
cooling applications from 2 through 5 tons (7.0 through
17.6 kW). Refer to Engineering Handbook for proper siz­
ing.
Units are factory equipped for use with natural gas. A kit is
available for conversion to LPG operation. All ML193UH
units are equipped with a hot surface ignition system. The
gas valve is redundant to assure safety shut-off as required
by C.S.A.
The heat exchanger, burners and manifold assembly can
be removed for inspection and service. The maintenance
section gives a detailed description on how this is done.
All specifications are subject to change. Procedures out­
lined in this manual are presented as a recommendation
only and do not supersede or replace local or state codes.
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at discon­
nect switch(es). Unit may have multiple
power supplies.

Table of Contents

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Corp. 1025-L5
Revised 03-2014
ML193UH SERIES UNITS
2
3
. . . . . . . . . . . . . . . . . . . . . .
4
7
. . . . . . . . . . . . . . . . . . . .
19
40
. . . . . . . . . . . . . .
41
. . . . . . . . . . . . . . . . .
43
44
. . . . . .
47
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, person­
al injury or loss of life. Installation and service must
be performed by a licensed professional HVAC in­
staller (or equivalent), service agency or the gas sup­
plier.
Sharp edges.
Be careful when servicing unit to avoid sharp edges
which may result in personal injury.
Page 1
ML193UH
WARNING
© 2014 Lennox Industries Inc.
Litho U.S.A.

Advertisement

Table of Contents
loading

Related Manuals for Lennox ML193UH045P36B

Summary of Contents for Lennox ML193UH045P36B

  • Page 1: Table Of Contents

    Service Literature ML193UH SERIES UNITS ML193UH series units are high-efficiency gas furnaces manufactured with Lennox DuralokPlust aluminized steel clamshell-type heat exchangers, with a stainless steel con­ densing coil. ML193UH units are available in heating input capacities of 44,000 to 132,000 Btuh (13 to 38.6 kW) and cooling applications from 2 through 5 tons (7.0 through...

  • Page 2: Specifications

    SPECIFICATIONS Model No. ML193UH045P36B ML193UH070P24B ML193UH070P36B ML193UH090P36C Heating AFUE Performance Input - Btuh 44,000 66,000 66,000 88,000 Output - Btuh 42,000 62,000 62,000 83,000 Temperature rise range - °F 25 - 55 50 - 80 40 - 70 50 - 80 Gas Manifold Pressure (in.

  • Page 3: Optional Accessories

    OPTIONAL ACCESSORIES - MUST BE ORDERED EXTRA “B” Width “C” Width “D” Width Models Models Models CABINET ACCESSORIES Horizontal Suspension Kit - Horizontal only 51W10 51W10 51W10 Return Air Base - Upflow only 50W98 50W99 51W00 CONDENSATE DRAIN KITS Condensate Drain Heat Cable 6 ft.

  • Page 4: Blower Performance Data

    BLOWER DATA ML193UH045P36B PERFORMANCE (Less Filter) ML193UH090P36C PERFORMANCE (Less Filter) Air Volume / Watts at Various Blower Speeds Air Volume / Watts at Various Blower Speeds External External Medium- Medium- Medium- Medium- Static Static High High High High Pressure Pressure in.
  • Page 5 BLOWER DATA ML193UH110P60C PERFORMANCE (Less Filter) Air Volume / Watts at Different Blower Speeds Bottom Return Air, Side Return Air with Optional Return Single Side Return Air − Air volumes in bold require field External Air Base, Return Air from Both Sides or Return Air from fabricated transition to accommodate 20 x 25 x 1 in.
  • Page 6 ML193UH PARTS IDENTIFICATION FLEXIBLE NO-HUB EXHAUST COLLAR BURNER BOX TOP CAP MANIFOLD ASSEMBLY GAS VALVE DuralokPlus HEAT EXCHANGER ASSEMBLY FLUE COLLAR COMBUSTION AIR INDUCER BURNER ACCESS PANEL CABINET BAG ASSEMBLIES (shipping location) PRIMARY LIMIT COMBUSTION AIR PRESSURE SWITCH SIGHT BLOWER GLASS COLD END ASSEMBLY...

  • Page 7: I-Unit Components

    I-UNIT COMPONENTS WARNING ML193UH unit components are shown in figure 1. The combustion air inducer, gas valve and burners can be ac­ Shock hazard. cessed by removing the burner access panel. The blower Disconnect power before servicing. Control is not and control box can be accessed by removing the blower field repairable.
  • Page 8 tial in the prove switch is great enough, the prove switch Fan Control closes and a 15-second pre-purge begins. If the prove The fan on time of 30 seconds is not adjustable. The fan off delay (amount of time that the blower operates after the switch is not proven within 2-1/2 minutes, the integrated heat demand has been satisfied) may be adjusted by control goes into Watchguard-Pressure Switch mode for a...
  • Page 9 The integrated control is equipped with two LED lights for troubleshooting. The diagnostic codes are listed below in table 3. TABLE 3 DIAGNOSTIC CODES Make sure to Identify LED'S Correctly. LED #1 (Red) LED #2 (Green) DESCRIPTION Power on - Normal operation. SIMULTANEOUS SIMULTANEOUS Also signaled during cooling and continuous fan.
  • Page 10 4. Integrated Ignition Control 103085 (A92) TABLE 5 12-Pin Terminal Designations PIN # FUNCTION WARNING High Limit Output Sensor Shock hazard. 24V Line Disconnect power before servicing. Control is not Not Used field repairable. If control is inoperable, simply re­ place entire control.
  • Page 11 INTEGRATED CONTROL (Automatic Hot Surface Ignition System) TERMINAL DESIGNATIONS Humidifier (120VAC) Input (120VAC) LINE Transformer (120VAC) XFMR Indoor Air Qality Accessory Air Cleaner (120VAC) Blower - Cooling Speed (120VAC) COOL Blower - Heating Speed (120VAC) HEAT Dead terminals to park alternate spd taps PARK Continuous blower CONT...
  • Page 12 Fan Time Control Twinning 2 ML193UH Furnaces Heating Fan On Time Integrated control 103085 is equipped with a provision to ”twin” (interconnect) two(2) adjacent furnaces with a com­ The fan on time of 30 seconds is not adjustable. mon plenum such that they operate as one (1) large unit. Heating Fan Off Time When twinned, the circulating blower speeds are synchro­...
  • Page 13 FIELD WIRING FOR TWINNING THE ML193UH TWIN TWIN SINGLE STAGE THERMOSTAT TWO-STAGE THERMOSTAT Call For Cool Call For Cool TWIN 1 TWIN 1 Call For Fan Call For Fan Call For 1st Call For Heat Stage Heat Call For 2nd StageHeat TWIN TWIN...
  • Page 14 B-Heating Components out removing any part of the burners. During operation, flame is sensed by current passed through the flame and Combustion air inducer (B6), primary limit control (S10), sensing electrode. The ignition control allows the gas valve SureLight ignitor, burners, flame rollout switch (S47), gas to remain open as long as flame signal is sensed.
  • Page 15 IGNITOR CHECKS TABLE 7 Control Ohms Voltage + 10% 39 to 70 103085 Test 1 24 to 47 100973 Check ignitor circuit for correct resistance. Remove 4-pin plug from control. Check ohms reading across terminals 2 and 4. See table 7. If value is correct, this is the only test needed. If the reading on the meter is not correct, (0 or infinity) then a second test is needed.
  • Page 16 4. Primary Limit Control (Figure 12) burner input. See table 8 for orifice size. The burner is sup­ ported by the orifice and will easily slide off for service. A Primary limit (S10) used on ML193UH units is located in the flame retention ring in the end of each burner maintains heating vestibule panel.
  • Page 17 8. Combustion Air Inducer (B6) Pressure Switch & Cold End Header Box All ML193UH units use a combustion air inducer to move air through the burners and heat exchanger during heating operation. The blower uses a shaded pole 120VAC motor. The motor operates during all heating operation and is con­...
  • Page 18 Measuring Pressure Differential RED TUBING NEGATIVE BLACK TUBING POSITIVE 1 - Remove thermostat demand and allow unit to cycle 4 - Operate unit and observe manometer reading. off. Readings will change as heat exchanger warms. 2 - Install a tee in the negative (-) line (red tubing) and a a.

  • Page 19: Placement And Installation

    II-PLACEMENT AND INSTALLATION IMPORTANT Pipe & Fittings Specifications ML193UH exhaust and intake connections are made All pipe, fittings, primer and solvent cement must conform of PVC. Use PVC primer and solvent cement when with American National Standard Institute and the Ameri­ using PVC vent pipe.

  • Page 20: Joint Cementing Procedure

    TABLE 12 OUTDOOR TERMINATION USAGE* STANDARD CONCENTRIC Flush­ Wall Kit Wall Ring Kit 1-1/2 inch 2 inch 3 inch Mount Vent 2 inch 3 inch 2 inch Pipe Input Size Field 51W11 Dia. in. 71M80 69M29 Fabricated 44J40 (US) 22G44 (US) (US) (US) 60L46 (US)

  • Page 21: Venting Practices

    Venting Practices REPLACING FURNACE THAT CHIMNEY WAS PART OF A COMMON OR GAS VENT VENT SYSTEM (Check sizing for water heater only) FURNACE WATER Piping Suspension Guidelines (Replaced HEATER by ML193) SCHEDULE 40 OPENINGS PVC - 5' (To Adjacent all other pipe* - 3' Room) * See table 11 for allowable pipe.
  • Page 22 Vent Piping Guidelines MINIMUM VENT PIPE LENGTHS ® ML193UH MIN. VENT LENGTH* NOTE - Lennox has approved the use of DuraVent manu­ MODEL factured vent pipe and terminations as an option to PVC. 15 ft. or 045, 070, 090, 110 ®...
  • Page 23 TABLE 14 Maximum Allowable Intake or Exhaust Vent Length in Feet NOTE - Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must be same pipe size. NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.
  • Page 24 TYPICAL EXHAUST PIPE CONNECTIONS IN UPFLOW DIRECT OR NON-DIRECT VENT APPLICATIONS Pipe size determined in table 14 2” 3” 2” 2” 2” 2” TRANSITION EXHAUST *2” DO NOT transition from smaller to larger pipe in horizontal runs of exhaust pipe. * When transitioning up in pipe size, use the shortest length of 2”...
  • Page 25 TYPICAL AIR INTAKE PIPE CONNECTIONS IN UPFLOW DIRECT VENT APPLICATIONS Pipe size determined in table 14 2” 3” TRANSITION AIR INTAKE 2” *2” 2” 2” 2” * When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible. NOTE −...
  • Page 26 Intake Piping TYPICAL AIR INTAKE PIPE CONNECTIONS The ML193UH furnace may be installed in either direct HORIZONTAL NON−DIRECT VENT APPLICATIONS vent or non-direct vent applications. In non-direct vent (Horizontal Right−Hand Air Discharge Application Shown) applications, when intake air will be drawn into the furnace from the surrounding space, the indoor air quality must be considered and guidelines listed in Combustion, Dilution PVC pipe...
  • Page 27 General Guidelines for Vent Terminations CAUTION In Non‐Direct Vent applications, combustion air is taken If this unit is being installed in an application with from indoors and the flue gases are discharged to the out­ combustion air coming in from a space serviced by doors.
  • Page 28 TABLE 16 Maximum Allowable Exhaust Vent Pipe Length (in ft.) Without Insulation In Unconditioned Space For Winter Design Temperatures Single - Stage High Efficiency Furnace Unit Input Size Winter Design Vent Pipe Temperatures °F (°C) Diameter 2 in. 32 to 21 (0 to -6) 2-1/2 in.

  • Page 29: Vent Termination Clearances

    ‡ Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible. FIGURE 31...
  • Page 30 ‡ Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible. FIGURE 32 Page 30...
  • Page 31 Details of Intake and Exhaust Piping Terminations for 6. On field supplied terminations, a minimum distance between the end of the exhaust pipe and the end of the Direct Vent Installations intake pipe without a termination elbow is 8” and a NOTE - In Direct Vent installations, combustion air is taken minimum distance of 6”...
  • Page 32 7. If intake and exhaust piping must be run up a side wall to position above snow accumulation or other ob­ structions, piping must be supported. At least one 12” EXHAUST (305mm) bracket must be used within 6” from the top of the el­ VENT 5-1/2”...
  • Page 33 FIELD FABRICATED WALL TERMINATION NOTE − FIELD−PROVIDED REDUCER MAY BE 2” (51mm) 3” (76mm) REQUIRED TO ADAPT LARGER VENT PIPE SIZE Vent Pipe Vent Pipe TO TERMINATION A− Minimum clearance above grade or average 12” (305 mm) 12” (305 mm) snow accumulation B−...
  • Page 34 Details of Exhaust Piping Terminations for Non‐Direct ML193UH NON-DIRECT VENT APPLICATION Vent Applications USING EXISTING CHIMNEY Exhaust pipes may be routed either horizontally through an SIZE TERMINATION STRAIGHT-CUT OR outside wall or vertically through the roof. In attic or closet ANGLE-CUT IN DIRECTION PIPE PER TABLE 17.
  • Page 35 Heating cable kit is sate trap, filter rack must be installed beyond available from Lennox in various lengths; 6 ft. (1.8m) - condensate trap or trap must be re-located to kit no. 26K68; 24 ft. (7.3m) - kit no. 26K69; and 50 ft.
  • Page 36 ML193UH With Evaporator Condensate Trap With Optional Overflow Switch Coil Using A Separate Drain From Evaporator Coil Evaporator drain Horizontal Furnace 4” Min. to 5” Max.above line required condensate drain connection) Field Provided Vent (1” min. 2” max. above condensate connec­ FurnaceCondensate tion) Drain Connection...
  • Page 37 ML193UH with Evaporator IMPORTANT Coil Using a Common Drain When combining the furnace and evaporator Evaporator drain line required coil drains together, the A/C condensate drain outlet must be vented to relieve pressure in or­ der for the furnace pressure switch to operate properly.
  • Page 38 TRAP / DRAIN ASSEMBLY USING 1/2” PVC OR 3/4” PVC COLD END HEADER BOX WITH 3/4 DRAIN CONNECTION Optional Condensate Drain Connection Adapter 3/4 inch slip X 3/4 inch mpt (not furnished) 90° Street Elbow 3/4 inch PVC (not furnished) Adapter 3/4 inch slip X 3/4 inch mpt (not furnished) Condensate Drain...
  • Page 39 TRAP / DRAIN ASSEMBLY USING 1/2” PVC OR 3/4” PVC COLD END HEADER BOX WITH 1/2” DRAIN CONNECTION Optional Condensate Drain Connection Adapter 1/2 inch slip X 1/2 inch mpt (Not Furnished) 90° Street Elbow 1/2 inch PVC (Not Furnished) Adapter 1/2 inch slip X 1/2 inch mpt (Not Furnished) Condensate Drain...

  • Page 40: Iii-Start-Up

    III-START‐UP 2 - Set the thermostat to the lowest setting. 3 - Turn off all electrical power to the unit. A-Preliminary and Seasonal Checks 4 - This furnace is equipped with an ignition device which 1 - Inspect electrical wiring, both field and factory installed automatically lights the burners.

  • Page 41: Iv-Heating System Service Checks

    Gas Leak Detector is strongly recommended. It is available through Lennox under part number 31B2001. NOTE - Shut unit off and remove manometer as soon as an See Corp. 8411-L10, for further details.
  • Page 42 TABLE 19 arately and manifold pressure de-rate. See table 20 or ML193 table 21 for manifold pressures at varying altitudes. Table For Nat For L.P. Unit 22 lists conversion kit and pressure switch requirements at -045 varying altitudes. -070 The combustion air pressure switch is factory-set and re­ -090 7.2 - 7.9 8.6 - 9.3...

  • Page 43: V-Typical Operating Conditions

    2 - Generally, blower operation is set at thermostat sub­ base fan switch. With fan switch in ON position, blower A transducer (Part #78H5401 available from Lennox Re­ operates continuously. With fan switch in AUTO posi­ pair Parts) is required to measure flame signal if meter tion, blower cycles with demand or runs continuously used will not read a low micro amp signal.

  • Page 44: Vi-Maintenance

    Before using any filter with this system, check the specifications provided by the filter manufacturer Hose Hose against the data given in the appropriate Lennox Product Specifications bulletin. Additional informa­ tion is provided in Service and Application Note FIGURE 58 ACC­00­2 (August 2000).
  • Page 45 Cleaning Heat Exchanger 22 - Remove screws along vestibule sides and bottom which secure vestibule panel and heat exchanger as­ If cleaning the heat exchanger becomes necessary, follow sembly to cabinet. Remove two screws from blower the below procedures and refer to figure 1 when disassem­ rails which secure bottom heat exchanger flange.
  • Page 46 Cleaning the Burner Assembly spect the inside of the burners and crossovers for any blockage caused by foreign matter. Remove any 1 - Turn off gas and electrical power to the furnace. Re­ blockage move heating compartment access panel. 10 - Reinstall the burner/manifold assembly using the ex­ 2 - Disconnect the gas supply line from the gas valve.

  • Page 47: Vii-Sequence Of Operation And Flow Charts

    VII-WIRING DIAGRAM AND SEQUENCE OF OPERATION ML193UH With Integrated Control 100973 1 - When there is a call for heat, W1 of the thermostat en­ 5 - Gas valve opens for a 4-second trial for ignition ergizes W of the furnace control with 24VAC. 6 - Flame is sensed, gas valve remains open for the heat 2 - S10 primary limit switch and S47 rollout switch are call.
  • Page 48 Sequence of Operation Flow Chart - Integrated Control 100973 HEATING SEQUENCE OF OPERATION ABNORMAL HEATING MODE NORMAL HEATING MODE POWER ON GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER DELAY OFF. CONTROL SELF-CHECK OKAY? LED #1 ON LED #2 ON (RESET CONTROL BY TURNING MAIN POWER OFF.) POLARITY REVERSED.
  • Page 49 HEATING SEQUENCE CONTINUED NORMAL HEATING MODE ABNORMAL HEATING MODE 15‐SECOND COMBUSTION AIR INDUCER PREPURGE INITIATED BY CLOSED PRESSURE SWITCH. LEDS SIGNAL ALTERNATING FAST FLASH UNTIL IS VOLTAGE ABOVE 90 VOLTS? IGNITOR WARM‐UP -- 20 SECONDS. VOLTAGE IS ABOVE 95 VOLTS, THEN RESTARTS HEATING 4‐SECOND TRIAL FOR IGNITION.
  • Page 50 COOLING SEQUENCE OF OPERATION NORMAL COOLING MODE ABNORMAL COOLING MODE POWER ON IGNITION CONTROL MAIN POWER ON. GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF WITH NORMAL DELAY. CONTROL SELF DIAGNOSTIC CHECK. SIGNAL CIRCUIT CONTROL FAILURE AT LED. IS CONTROL OPERATING NORMALLY? INTERRUPT MAIN POWER TO RESET CONTROL.
  • Page 51 CONTINUOUS HEAT SPEED FAN SEQUENCE OF OPERATION LED: SLOW FLASH RATE REMAINS UNCHANGED THROUGHOUT SEQUENCE. MANUAL FAN SELECTION MADE AT THERMOSTAT. CONTROL (G) ENERGIZES SYSTEM FAN AT HEAT SPEED. EAC TERMINAL IS ENERGIZED. HUM TERM. ENERGIZES THERMOSTAT CALLS FOR HEAT (W). WITH COMB.
  • Page 52 ML193UH With Integrated Control 103085 1 - When there is a call for heat, W1 of the thermostat en­ 5 - Gas valve opens for a 4-second trial for ignition ergizes W of the furnace control with 24VAC. 6 - Flame is sensed, gas valve remains open for the heat 2 - S10 primary limit switch and S47 rollout switch are call.
  • Page 53 Sequence of Operation Flow Chart - Integrated Control 103085 HEATING SEQUENCE OF OPERATION ABNORMAL HEATING MODE NORMAL HEATING MODE POWER ON GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER DELAY OFF. CONTROL SELF-CHECK OKAY? LED: OFF POLARITY REVERSED. IS POLARITY CORRECT? LED: 9 FLASHES IMPROPER GROUND.
  • Page 54 HEATING SEQUENCE CONTINUED NORMAL HEATING MODE ABNORMAL HEATING MODE 15‐SECOND COMBUSTION AIR INDUCER PREPURGE INITIATED BY CLOSED PRESSURE SWITCH. LED: ON STEADY UNTIL VOLTAGE IS IS VOLTAGE ABOVE 90 VOLTS? IGNITOR WARM‐UP -- 20 SECONDS. ABOVE 95 VOLTS, THEN RESTARTS HEATING SEQUENCE.
  • Page 55 COOLING SEQUENCE OF OPERATION NORMAL COOLING MODE ABNORMAL COOLING MODE POWER ON IGNITION CONTROL MAIN POWER ON. LED: ON STEADY GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF WITH NORMAL DELAY. CONTROL SELF DIAGNOSTIC CHECK. LED: OFF IS CONTROL OPERATING NORMALLY? INTERRUPT MAIN POWER TO RESET CONTROL.

This manual is also suitable for:

Ml193uh070p36bMl193uh070p24bMl193uh090p36cMl193uh090p48cMl193uh110p48cMl193uh110p60c ... Show all

Table of Contents