background image

11

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

LENNOX HEARTH PRODUCTS  •  MERIT PLUS

®

 B-VENT GAS FIREPLACES (MPB33/35/40/45)  •  INSTALLATION INSTRUCTIONS

STEP 4. FIELD WIRING

       

CAUTION

The ground supply lead must be 

connected to the wire attached to the 

green ground screw located on the 

outlet box 

(see wiring diagrams)

Failure to do so will result in a 

potential safety hazard. The appli-

ance must be electrically grounded 

in accordance with local codes or, 

in the absence of local codes, the 

National Electrical Code, ANSI/

NFPA 70 - latest edition (in Canada, 

the current CSA C22.1 Canadian 

Electrical Code).

CAUTION: Label all wires prior to discon-

nection when servicing controls. Wiring 

errors can cause improper and dangerous 

operation. 

ATTENTION: Au moment de l’entretien 

des commandes, étiquetez tous les fils 

avant de les débrancher. Des erreurs de 

cáblage peuvent entraîner un fonc-

tionnement inadéquat et dangereux.

Verify proper operation after servicing.

S’assurer que l’appareil fonctionne adé-

quatement une fois l'entretien terminé.

Refer to Section A for millivolt appliances 

and Section B for electronic appliances. The 

gas valve is set in place and pre-wired at the 

factory on both models.

A. Millivolt Wiring

 

(see Figure 18)

Millivolt units are not provided with any factory-

installed controls; therefore, one of the optional 

control switches is required to operate the unit 

(ON/OFF Wall Switch, Unit-Mountable ON/OFF 

Switch*, Remote Control). See the fireplace 

Care and Operation Instructions for details.

[*If using a Unit-Mountable ON/OFF Rocker 

Switch with an optional Style View Door, 

mount the Rocker Switch on the door instead 

of the unit.]

1

.  If installing an ON/OFF wall switch or 

receiver, mount it in a convenient location 

on a wall near the fireplace.

2

.  Wire the control switch within the millivolt 

control circuit using the 15 feet of 2 

conductor wire supplied with the unit.

NOTE:

 The supplied 15 feet of 2 conductor wire 

has one end of each conductor connected to 

the gas valve circuit and the other end of each 

conductor placed loose inside the bottom 

compartment.

P/N 580491-01

JUNCTION BOX

120V AC

REMOTE RECEIVER

ON/OFF SWITCH

WALL SWITCH

SAFETY LIMIT SWITCH

B-VENT MODELS ONLY

AC/DC 

POWER 

ADAPTOR

HOT

NEUTRAL

OPTIONAL

GROUND

BATTERY HOLDER

DFC WIRE HARNESS

SPARK WIRE CABLE

PILOT GROUND WIRE

PILOT 

SENSOR

CABLE

HOOD

IGNITER ROD

FLAME SENSOR

PILOT TUBE

 

CPI

 

SWITCH

OFF (O) = INTERMITTENT PILOT MODE
ON   (-) = STANDING PILOT MODE

PROFLAME DFC BOARD

PROFLAME VALVE

ELECTRONIC PILOT ASSEMBLY

B   = BLACK

BR = BROWN

GY = GRAY

PU = PURPLE

R   = RED

BL  = BLUE

G  = GREEN

O  = ORANGE

W  = WHITE

Y   = YELLOW

WIRING COLOR CODE

B

B

B

R

R

W

W

B

B

B

B

BL

BL

G

G

O

Y

Y

R

R

Y

W

G

G

O

SCHEMATIC REPRESENTATION ONLY

Figure 17 - SIT Milivolt Wiring 

Diagram

If any of the original wire as supplied must be replaced, 

it must be replaced with Type AWM105 

° 

C –  18 GA. wire. 

Thermopile 

H T 

P T 

H T 

P T 

*TWIST WIRES  “ A ”  AND  “ B ”  TOGETHER TO OPERATE UNIT 

SOLELY BY MANIPULATING THE GAS VALVE CONTROL KNOB; 

OR CONNECT WIRES TO  OPTIONAL ON/OFF SWITCH OR WALL 

SWITCH OR REMOTE CONTROL RECEIVER TO OPERATE UNIT.

*OPTIONAL ON/OFF SWITCH,

 WALL SWITCH, OR REMOTE

CONTROL RECEIVER

A

H C 

T I 

W S   

T I 

M I 

WT 

BK 

BK 

BK 

Schematic Representation Only 

Figure 18 - Optional J-Box/Outlet Box

 

  (Left Side Shown)

See 

Figure 12

 on 

Page 9

 

for Optional Electrical Inlet 

Knockout Location.

* Field-Provided 

Junction Box and 

Duplex Receptacle

* Narrow (2-1/8" Wide)

   J-Box Required

CAUTION: ENSURE THAT WIRES ARE POSI-

TIONED AWAY FROM  HOT SURFACES AND 

SHARP EDGES.

Figure 16 - Wiring Diagram - Electronic Gas Valves

B. Electronic Wiring

 

(see Figure 18) 

One of the following optional controls also 

may be used: ON/OFF Wall Switch, Remote 

Control (see fireplace Care and Operation 

Instructions for details.).

NOTE: 

Electronic models must be connected 

to the main power supply.

1

.  Route a 3-wire 120Vac 60Hz 1ph power 

supply to the appliance junction box.

2

.  Remove the electrical inlet cover plate from 

the side of the unit by removing the plate’s 

securing screws (see 

Figure 12 on

 

Page 

9

).

3

. Remove the cover plate knockout; then 

feed the power supply wire through 

the knockout opening and into the unit 

junction box.

4

.  See 

Figure 18

. Connect the 

black power 

supply wire to the lower outlet’s red 

pigtail lead

  Connect the 

white power supply wire to 

the outlet’s common terminal

5

. Connect the 

ground supply wire to the 

pigtail lead attached to the outlet’s green 

ground screw.

NOTE: 

Remote receiver should be located in the 

wall, or if installed in the control compartment, 

pulled all the way forward and completely to the 

left or right against the corner posts. 

 CAUTION

In millivolt systems, do not connect 

optional control switch to 120 V power 

supply.

Summary of Contents for MPB33CNE

Page 1: ... SURFACE VITRÉE CHAUDE PEUT CAUSER DES BRÛLURES LAISSER REFROIDIR LA SURFACE VITRÉE AVANT D Y TOUCHER NE PERMETTEZ JAMAIS À UN ENFANT DE TOUCHER LA SURFACE VITRÉE EL VIDRIO CALIENTE CAUSARÁ QUEMADURAS USTED DEBE NUNCA TOCAR EL VIDRIO CALIENTE LOS NIÑOS DEBEN NUNCA TOCAR EL VIDRIO Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance WHAT ...

Page 2: ...on 5 Vent Termination Clearances 5 Appliance and Vent Clearances 6 Pre Installation Steps 7 Typical Installation Sequence 7 Detailed Installation Steps 7 Step 1 Framing 7 Framing Specifications 8 Fireplace Specifications 9 Step 2 Routing Gas Line 9 Step 3 Installing Vent System 10 Step 4 Field Wiring 11 Step 5 Wiring Optional Forced Air Blower Kit 12 Step 6 Connecting Gas Line 12 Step 7 Installing...

Page 3: ...nal Safety Standards and are tested and listed by OMNI Test Laboratories Inc Report No 116 F 36d 5 toANSIZ21 50b 2009 inCanada CSA 2 22b 2009 and CAN CGA 2 17 M91 R2009 in both USA and Canada as vented gas fireplaces Bothmillivoltandelectronicversionsofthese appliances may be used in bedrooms only when the room is an unconfined space as defined by the National Fuel Gas Code Use in bedrooms may not...

Page 4: ...onin the US state of Massachusetts if the following additional requirements are met Install this appliance in accordance with Massachusetts Rules and Regulations 248 C M R Installation and repair must be done by a plumber or gas fitter licensed in the Com monwealth of Massachusetts The flexible gas line connector used shall not exceed 36 inches 92 centimeters in length The individual manual shut o...

Page 5: ...d out of traffic and away from furniture and draperies Figure 3 En raison des températures élevées l appareil devrait être installé dans un endroit où il y a peu de circulation et loin du mobilier et des tentures Figure 3 The location should also be free of electrical plumbing or other heating air conditioning ducting Be aware that this is a heat producing ap pliance Objects placed above the unit ...

Page 6: ... side of the fireplace may abutt a perpendicular wall For this type of installation the other side of the fireplace must be a flat wall to allow for proper air flow and burner operation Combustiblematerialsmayprojectbeyondone or both sides of the fireplace opening when these materials are kept within the Safe Zone illustrated in Figure 6 3 1 2 in 89mm Top View of Fireplace Combustiblematerials may...

Page 7: ...abs one on each side located at the base of the fireplace and secure to the floor by nailing with 8d nails or equivalent see Figure 10 Anchor Tab Step 10 REMOVING AND Installing THE Glass Door Page 19 Step 11 Burner Adjustments Page 19 Adjust burner primary air shutter to achieve proper flame appearance Step 12 TESTING VENT OPERATION Page 21 Vent operation test and safety limit switch operation St...

Page 8: ... Enclosure Including Finishing Materials if any Rough Framing Face Unfinished Shown o N l e d o M A t i n U e z i S A g n i m a r F e z i S B C D E F G H J K n i 5 3 8 1 5 3 4 1 5 3 4 1 9 1 8 5 9 1 7 5 2 1 4 3 8 2 6 1 4 6 1 9 6 8 5 0 4 m m 2 9 8 5 9 8 5 9 8 3 8 4 8 9 4 0 6 4 1 0 3 7 6 0 4 2 0 1 7 6 1 2 3 0 1 n i 8 1 0 4 4 1 0 4 4 1 0 4 4 2 8 5 4 2 6 1 3 1 1 6 6 1 1 0 3 6 1 4 6 1 9 6 2 3 1 1 3 4 m ...

Page 9: ...lynoone unfamiliarandunqualifiedshouldattemptsizing or installing gas piping NOTES All appliances are factory equipped with a flexible gas line connector and 1 2 shutoff valve see Figure 21 on Page 13 Step 2 ROUTING Gas Line Routea1 2 13mm gaslineasshowninFigure 13 Gas lines must be routed constructed and made of materials that are in strict accordance withlocalcodesandregulations Theappliance as ...

Page 10: ...rtical is used or 15 4 6 m when an offset is greater than 45 degrees and up to 60 degrees see Figure 17 The offset may start at the fireplace flue collar The maximum overall height of the vent system and appliance should not exceed 40 feet Install the B vent system in accordance with the vent manufacturer s instructions Required Pipe Diameter MPB33 series Requires 4 102 mm MPB35 series Requires 5 ...

Page 11: ...TIONAL GROUND BATTERY HOLDER DFC WIRE HARNESS SPARK WIRE CABLE PILOT GROUND WIRE PILOT SENSOR CABLE HOOD IGNITER ROD FLAME SENSOR PILOT TUBE CPI SWITCH OFF O INTERMITTENT PILOT MODE ON STANDING PILOT MODE PROFLAME DFC BOARD PROFLAME VALVE ELECTRONIC PILOT ASSEMBLY B BLACK BR BROWN GY GRAY PU PURPLE R RED BL BLUE G GREEN O ORANGE W WHITE Y YELLOW WIRING COLOR CODE B B B R R W W B B B B BL BL G G O ...

Page 12: ... the grounding prong from the plug Step 6 Connecting Gas Line Make gas line connections All codes require a shut off valve mounted in the supply line The orientation of the shut off valve should face the front see Figure 22 Figure 21 illustrates two methodsforconnectingthegassupply Theflex line method is acceptable in the U S however Canadian requirements vary depending on locality Installation mu...

Page 13: ... DONOTterminatetheductcloserthan3 below the chimney top Outside supplemental combustion air ducting may be run upwards or vertically through framing and ceiling joists with the hood installed through an outside wall and 3 1 m belowthetermination Ductingmayalsoberun downward through floor joists and under the hometoaventilatedcrawlspacenotconsidered part of the living area of the home Outside Air C...

Page 14: ... for MPB35 Series appliances and Figure 30 for MPB40 and MPB45 Series appliances NOTE Turn off all electricity to the appliance before you install volcanic stone embers and logs The flame should project 1 25 mm beyond the hood at all three ports see Figure 24 Replace logs if removed for pilot inspection To light the burner turn ON the remote wall switch and rotate the gas valve control knob counte...

Page 15: ...nt door see Removing the Glass Enclosure Panel on Page 19 Step 2 Install decorative volcanic stone Sprinkle the decorative volcanic stone in a pleasing pattern The volcanic stone should be placed directly on top of the firebox bottom along the front and to the back at the right and left sides of the burner Position any optional ceramic fiber liners before placing the stone Logs should be positione...

Page 16: ...upper end Place the left log and then the smaller left and right top logs All logs that have notches to fit over the grate tines should be positioned with these notches directly against the grate All top logs that rest on lower logs do so over flattened mounting faces in the bottom logs Properlogandtwigplacementiscriticaltoencourageoutstanding flame appearance and prevent sooting 3 2 4 5 6 1 2 3 4...

Page 17: ... placed in the order shown Position the rear log on the brackets at the rear of the firebox with the log s notches directly over the brackets Position the right log log no 3 by inserting the pin from the rear log into the hole on its upper end Place the left log and then the smaller left and right top logs All logs that have notches to fit over the grate tines should be positioned with these notch...

Page 18: ...ion the individual logs as shown below Logs should be placed in the order shown Position the center log on the burner first then place the glowing embers as shown in Figure 27 Place the rear log both the right and left and then the smaller left and right top logs All logs that have notches to fit over the grate tines should be positioned with these notches directly against the grate All top logs t...

Page 19: ...t appear sooty NOTE Thefollowingchartisprovidedtoaidyou in achieving the correct air shutter adjustment for your installation Removing the Glass Enclosure Panel see Figure 31 Removethetoplouverassembly Openthelower control compartment door see Figure 22 on Page 13 by pressing in simultaneously at the left and right top corners of the door the door is hinged at the bottom Remove the bottom compartm...

Page 20: ...position 1 Refer to Figures 32 33 and 34 for proper flame appearance To adjust the flame refer to Figure 35 and move the rod up and down the adjustment rod is located in the lower control area Position the air shutter to the factory setting as shown in Table 8 2 Light appliance follow lighting procedure on lighting label in control compartment or in the Care and Operation Instructions 3 Allow the ...

Page 21: ...ure 37 for its location If during appliance operation the flame goes out independently of the burner on off wall switch it may be due to a blocked vent If this condition occurs the safety limit switch will activate causing the fireplace burner to shut off To reset the safety limit switch perform the following steps NOTE Allow the appliance to cool completely 7 Remove the top louver panel 8 Reset t...

Page 22: ...de est utilisée pour contrôler le foyer nettoyez la soigneusement pour éliminer la poussière et les traces de graisse ou d huile Collez l étiquette sur le boîtier de la télécommande Figure B Choisissez la langue qui est principale ment parlée dans la résidence du propriétaire En cas de doute collez l étiquette en anglais 3 Si vous ne trouvez pas les étiquettes veuillez appeler Lennox Hearth Produc...

Page 23: ...sembly C Remove the burner assembly with attached venturi tube Millivolt and Electronic Ignition System Appliances Step 1 SIT Systems Refer to Figure 38 and the instructions provided with the SIT Regu lator Conversion Kit Using a Torx T20 driver to remove and discard the pressure regulator mounting screws two screws for electronic models three screws for millivolt models pressure regulator tower t...

Page 24: ...y proper burner ignition and operation See Burner Adjustments and Burner Flame Appearance on Pages 19 and 20 Step 12 Inspect the pilot system for proper flame The pilot flame should engulf the flame sensor as shown in Figures 24 and 25 on Page 14 Step 13 Using a manometer test the inlet and manifold gas pressures see Tables 2 and 3 on Page 4 ALWAYS TEST PRESSURES WITH THE VALVE REGULATOR CONTROL A...

Reviews: