Page 2 - LENNOX HEARTH PRODUCTS • MERIT; Care and Operation; WARNING
2 LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS PACKAGING The assembled vented gas fireplace heater is packaged with:• (1 set) Logs (packaged in a carton inside the firebox). • (1 bag) Glowing Embers (in bottom compart- ment). • Literat...
Page 3 - National; Table 1
3 LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS WARNING Improper installation, adjust- ment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information consult ...
Page 4 - Figure 1; Table 3; REQUIREMENTS FOR THE COMMON-; Table 2; Tables 2 and 3; Figure 1: SIT Millivolt Gas Valve; Series; Table 4
4 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Test gauge connections are provided on the front of the millivolt and electronic gas control valve (identified IN for the inlet and OUT...
Page 5 - HORIZONTAL VENT; LOCATION; Figure 8; COLd CLIMATE INSULATION; Figure 3: Typical Locations
5 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS HORIZONTAL VENT (Rear Vent Application with a chase) HORIZONTAL VENT (Top Vent Application) VERTICAL VENT (Top Vent Application) (Rear ...
Page 6 - Figure 5; VenT TerminaTion ClearanCes; These instructions should be used as a; Vertical Vent Termination Clearances; Figures; Termination Heights For Vents; Horizontal Vent Termination Clearances; Side Elevation View; Figure 6; Figure 4 - Multiple Terminations; minimum
6 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS 12 X Roof Pitch is X/12 2 FT MIN. 2 FT MIN. Lowest Discharge Opening H* *H = MINIMUM HEIGHT FROM ROOF TO LOWEST DISCHARGE OPENING OF VE...
Page 7 - EXTERIOR HORIZONTAL VENT TERMINATION CLEARANCE REQUIREMENTS; Figure 7
7 LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. EXTERIOR HORIZONTAL VENT TERMINATION CLEARANCE REQUIREMENTS Figure 7 V V V V V F C Fixed Closed Window Operable Window B B A B H M I = ...
Page 8 - MINIMUM CLEARANCES TO COMBUSTIBLES; When; Hearth Extension
8 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Models Combustible Shelf Height - Inches (millimeters) Top Vent - With One 90 degree Elbow Rear Vent - Straight Out The Back Secure Ven...
Page 9 - Figure 9: Minimum Mantel Clearances; MANTEL CLEARANCES; on
9 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Figure 9: Minimum Mantel Clearances Figure 10: Minimum Distance to Side Wall Combustible materials may project beyond one side of the f...
Page 10 - Side; combustible framing; Unit Secured to Framing; Header Spacing Top Standoffs; Bend up the appropriate header spacing top; PRE-INSTALLATION STEPS; See; TYPICAL INSTALLATION SEQUENCE; Remove cardboard before using appliance.
Pressure Relief Plates 10 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Side Framing Unit Nailing Flange (No clearance to combustible framing is required.) Unit Secured to Framing by ...
Page 11 - FIREPLACE ANd FRAMING SPECIFICATIONS; Vent Size; Vertical Venting through the Ceiling; Frame ceiling opening: Use a plumb line from the ceiling; above the appliance to locate center of the vertical run. Cut; Viewable Glass Size; Framing
11 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS G H Top View (Louvered Front Model Shown) Concentric Flue: Flue 4-1/2" (114 mm); Combustion Air 7-1/2" (190 mm).See Notes [1] ...
Page 12 - FIREPLACE FRAMING SPECIFICATIONS; Left Side Front; to; • MPdT-3328 ANd MPdR-3328 Models: Dimensions A through F occur when; one 45-degree elbow is connected directly to the appliance collar.; Back wall of chase/enclosure (including any finishing materials)
12 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS FIREPLACE FRAMING SPECIFICATIONS Schedule 40 Black Iron Pipe Inside diameter (Inches) Schedule 40 Pipe Length (feet) Natural Gas Propa...
Page 13 - Use only approved vent components (see; Approved Vent Components; Note: The vent restrictor is included in the; Step 3. PREPARING APPLIANCE VENT; VENT RESTRICTOR INSTALLATION; Step 4. INSTALLING VENT SYSTEM
13 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Use only approved vent components (see Approved Vent Components on Page 2). These fireplaces must be vented directly to the outside. T...
Page 14 - tf; use Firestop/Spacer; Effective Vent Length; Table 7; FlexTM pipe may also be used. A Vertical Vent; Tables on this page
14 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Note: Convert inches into metric equivalent measurement, as follows: Millimeters (mm) = Inches x 25.4 Centimeters (cm) = Inches x 2.54...
Page 15 - Vent / Appliance Collar; Note - Proper venting support is very important.
15 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Min. 10-1/2" (267 mm) Min. 10-1/2" (267 mm) First Vent ComponentAlign the dimple (four places) with the opening of the locking...
Page 16 - Swivel Joint
16 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Framing dimensions for Roof Pitch C d 0/12 10-1/2 in. 10-1/2 in. (267 mm) (267 mm) 6/12 10-1/2 in. 12 in. (267 mm) (305 mm) 12/12 10-1...
Page 17 - VERTICAL VENT FIGURES/TABLES; ideal, though rise per foot run ratios that are; Ratio V to H ratio is 1:2; together under any circumstances.; Ceiling Firestop/Spacer; Ceiling
17 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Figure 31: Rear Vent - ONE 90-DEGREE ELBOW Figure 30: Top Vent - STRAIGHT Figure 32: Top Vent - TWO 90-DEGREE ELBOWS VERTICAL VENT FIG...
Page 18 - to a maximum horizontal run of 20 feet.
18 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS TABLE C H +H 1 Maximum H Maximum V Minimum feet feet feet 5 (1.524) 2 (0.610) 1 (0.305) 10 (3.048) 4 (1.219) 2 (0.610) 15 (4.572) 6 (1...
Page 19 - Note: An elbow may also be attached to the; TYPICAL HORIZONTAL VENT INSTALLATION
19 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Figure 35 The unitized design of the Secure Vent compo- nents will engage and seal both the inner and outer pipe elements with the sam...
Page 20 - tion Guard; Figure; Venting Connection and Exterior Wall Recessing of the
20 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS IMPORTANT: The vent termination is hot while in operation and for a period of time following the use of the fireplace. To prevent cont...
Page 21 - Venting Components Required for Various Exterior Wall Thick-; HORIZONTAL VENT FIGURES/TABLES; Under no circumstances, may separate sections of; Spacer
21 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS H Maximum V Minimum feet feet 5 (1.524) 1 (0.305) 10 (3.048) 2 (0.610) 15 (4.572) 3 (0.914) 20 (6.096) 4 (1.219) V + H = 40 feet (12.2...
Page 22 - up to a maximum horizontal run of 20 feet.
22 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS TABLE H H +H 1 Maximum H Maximum V Minimum feet feet feet 5 (1.524) 2 (0.610) 1 (0.305) 10 (3.048) 4 (1.219) 2 (0.610) 15 (4.572) 6 (1...
Page 24 - Radius Minimum; SECuRE FlEx; Secure Flex; Attach Adapter to Appliance
24 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS 5" (127 mm) Radius Minimum Flexible Vent Section E. Attach Flex Vent to Termination - Secure Flex components can be purchased sepa...
Page 25 - Showing the Blower Wiring for the Optional; with an optional Style View Door, mount the Rocker; Note: The supplied 15 feet of 2 conductor; CAUTION; In millivolt systems, do NOT connect; Note: Electronic models must be connected to
25 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Step 5. FIELd WIRING TP-TH TP TH APPLIANCE- MOUNTED ON/OFF SWITCH (OPTIONAL) BK/W(1) BK/W(1) WALL-MOUNTED ON/OFF SWITCH (OPTIONAL) THE...
Page 26 - BLOWER CONTROL CIRCUIT WIRING; Junction Box; Step 7. CONNECTING GAS LINE
26 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Note: Remote receiver should be located in the wall, or if installed in the control compartment, pulled all the way forward and comple...
Page 27 - Step 8. VERIFYING APPLIANCE; Note: lighting Instructions are also found on; Piezo
27 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS B. Brush all joints and connections with the gas leak test solution to check for leaks. If bubbles are formed, or gas odor is detected...
Page 28 - GLOWING EMBERS ANd LOGS; NOTE: Turn off all electricity to the appliance; Bag of Glowing; Glowing Embers
28 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Step 9. INSTALL VOLCANIC STONE, GLOWING EMBERS ANd LOGS NOTE: Turn off all electricity to the appliance before you install volcanic st...
Page 29 - Log; Catalog Number for the entire log set: 24M15
29 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS 1 Log Number description (Stamped #) 1 Log, Rear (39-12) 2 Log, Left (39-1) 3 Log, Right (39-2) 4 Log, Top Center (39-13) 5 Log, Top/L...
Page 30 - Catalog Number for the entire log set: 24M22
30 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Figure 58 MPd-3530 LOG PLACEMENT Catalog Number for the entire log set: 24M22 Log Number description (Stamped #) 1 Log, Rear (39-5) 2 ...
Page 31 - Catalog Number for the entire log set: 24M25
31 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Figure 59 MPd-4035 ANd MPd-4540 LOG PLACEMENT Catalog Number for the entire log set: 24M25 1 Log Number description (Stamped #) 1 Log,...
Page 33 - WARNINGS; Light appliance (follow lighting procedure; Care and Operation Instructions; Allow the burner to operate for at least 15
33 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS WARNINGS • Air shutter adjustment should only be performed by a quali- fied professional service tech- nician. • Ensure front glass pa...
Page 34 - Louver Face Models; Adjustment Rod Up; Step 12. HOOd INSTALLATION; Refer to Figures 65 and 66. All models must; See Page 5 for
LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS 34 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. Figure 64 Combustible Finished Wall Materials Min. 1" (25 mm) This area must remain clear of combustible materials. Combustible ma...
Page 35 - Figure A; APPOSITION dES MISES EN GARdE RELATIVES
LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS 35 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. ATTACHING SAFETY-IN-OPERATION WARNINGS It is required that the safety instruction labels furnished with the fireplace be affixed to th...
Page 36 - INSTALLATION ACCESSORIES
36 LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. Listed Secure Vent™ Components Cat. No. Model description 77L70 SV4.5L6 6 Inch (152 mm) 77L71 SV4.5L12 12 Inch (305 mm) 77L72 SV4.5L24...
Page 37 - INSTALLATION ACCESSORIES CONTINUEd; All compressed flex vents can be expanded up to two times.
37 LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. Listed Secure Flex™ Components Cat. # Model description H1969 SF4.5HT-2 Horizontal Square Termina- tion for flex (without flex vent) 7...
Page 38 - Millivolt; assume les responsabilités liées à la conversion.
38 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Millivolt SIT Systems Propane Gas to Natural Gas Conversion Kits Models Catalog No. MPdT/R-3328 H2010 MPd-3530 H2012 MPd-4035 H2014 MP...
Page 39 - Pilot
39 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Burner Assembly Gas Valve Assembly Orifice Figure 67 Millivolt Appliances Step 4. SIT Systems - Refer to Figure 68 and the instruction...
Page 40 - Note: If the ignitor is damaged, a replacement; Model; Propane; Table 9
40 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS Retaining Clip Ignitor Assembly Pilot Assembly Pilot Orifice Flare Nut See Figure 71 and replace the pilot orifice as follows: Remove ...
Page 41 - NOTES
41 NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. LENNOX HEARTH PRODUCTS • MERIT ® PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • INSTALLATION INSTRUCTIONS NOTES
Lennox O23V4-105
Manual
Lennox G60UH(X)
Manual
Lennox SWI160
Manual
Lennox EST-50*
Manual
Lennox II-T C INS
Manual
Lennox LSBV-3628EN-H
Manual
Lennox ADAGIO-MN
Manual
Lennox Elite Series Gas Furnace Upflow/Horizontal Air Discharge
Manual
Lennox G61MP
Manual
Lennox CONDENSING UNITS
Manual
Lennox G32Q3-75
Manual
Lennox TK3-33PB
Manual
Lennox SLBV-35
Manual
Lennox MONTEST
Manual
Lennox BC-36/42-2
Manual
Lennox JX20
Manual
Lennox T300P
Manual