background image

Installation and Operation Instructions 

Document 1285A

H2364000A

 WARNING

If the information in this manual is not 

followed exactly, a fire or explosion may 

result causing property damage, personal 

injury or loss of life.

Do not store or use gasoline or other 

flammable vapors and liquids in the vicinity of 

this or any other appliance.

WHAT TO DO IF YOU SMELL GAS

•  Do not try to light any appliance.

•  Do not touch any electrical switch; do not 

use any phone in your building.

•  Immediately call your gas supplier from a 

nearby phone. Follow the gas supplier's 

instructions.

•  If you cannot reach your gas supplier, call 

the fire department.

Installation and service must be performed 

by a qualified installer, service agency, or gas 

supplier.

FOR YOUR SAFETY:

 This product must be installed and serviced by a professional service technician, 

qualified in hot water boiler and heater installation and maintenance. Improper installation and/or operation 

could create carbon monoxide gas in flue gases which could cause serious injury, property damage, or 

death. Improper installation and/or operation will void the warranty.

 AVERTISSEMENT

Assurez-vous de bien suivres les instructions 

données dans cette notice pour réduire au 

minimum le risque d’incendie ou d’explosion 

ou pour éviter tout dommage matériel, toute 

blessure ou la mort.

Ne pas entreposer ni utiliser d’essence ou ni 

d’autres vapeurs ou liquides inflammables dans 

le à proximité de cet appareil ou de tout autre 

appareil.

QUE FAIRE SI VOUS SENTEZ UNE ODEUR DE 

GAZ:

•  Ne pas tenter d’allumer d’appareils.

•  Ne touchez à aucun interrupteur. Ne pas vous servir 

des téléphones dans le bâtiment où vous vous 

trovez.

•  Appelez immédiatement votre fournisseur de 

gaz depuis un voisin. Suivez les instructions 

du fournisseur.

•  Si vous ne pouvez rejoindre le fournisseur de 

gaz, appelez le sservice des incendies.

L’installation et l’entretien doivent être assurés par 

un installateur ou un service d’entretien qualifié 

ou par le fournisseur de gaz.

Installation and Operation

Instructions for

M

ASCOT

 ® 

LX

Wall-Mounted, Modulating  
Boiler 

Model MLXH

50, 75, 100, 125, 150, 175, 

& 220 MBH

Combination Boiler 

Model MLXC

125, 150 and 175 MBH

Summary of Contents for MASCOT LX

Page 1: ...gas in flue gases which could cause serious injury property damage or death Improper installation and or operation will void the warranty AVERTISSEMENT Assurez vous de bien suivres les instructions d...

Page 2: ...al 13 3 3 3 Vertical Vent Terminal 15 3 3 4 Vertical Combustion Air Terminal 15 3 3 5 Installations in the Commonwealth of Massachusetts 15 3 4 Common Vent Test 16 SECTION 4 Gas Supply and Piping 4 1...

Page 3: ...ic Hot Water Priority MLXC only 37 9 7 Cascade Auto Configuration 38 SECTION 10 Set Up Instructions 10 1 Filling the Boiler System 39 10 2 Starting the Burner after Set Up 39 10 2 1 Burner Operation 3...

Page 4: ...he United States to the latest edition of the National Fuel Gas Code ANSI Z223 1 NFPA54 In Canada the installation must conform to the latest edition of CSA B149 1 Natural Gas and Propane Gas Installa...

Page 5: ...r components To remove these panels for further access into the Mascot LX there are two screws that hold each panel in place Remove the 2 screws on the upper panel and slide the upper metal panel up a...

Page 6: ...STION INLET HEAT EXCHANGER ASME TAG AUTOMATIC AIR VENT LOW WATER CUT OFF OPTIONAL EXHAUST SERVICE HATCH GAS SUPPLY HEAT EXCHANGER WATER PRESSURE SWITCH USER INTERFACE TEMPERATURE PRESSURE GAUGE GAS VA...

Page 7: ...ch your gas supplier call the fire department has been under water A Cet appareil n est pas dot d une veilleuse Il est quipe d un dispositif d allumage qui allume automatiquement le br leur Ne tentez...

Page 8: ...O 23 4 7 GAS GAS HYDRONIC OUTLET HYDRONIC OUTLET ELIMINATION AIR AIR VENT INLET EXHAUST VENT HYDRONIC INLET HYDRONIC INLET H F G E A D C CONDENSATE TRAP BOTTOM SIDE FRONT B DHW OUTLET DHW INLET J L K...

Page 9: ...3 4 33 2 5 30 1 2 78 18 46 4 5 8 12 3 4 7 5 1 4 14 2 5 2 3 4 7 12 3 4 33 1 3 4 5 35 1 2 90 18 46 8 7 8 23 3 4 7 5 1 4 14 2 5 38 1 2 90 18 46 8 7 8 23 J dimension applies for both the DHW OUTLET and D...

Page 10: ...appliance See Figure 6 1 Remove all packing and tie down materials 2 Check contents of the carton against items shown 1 PRV 2 PRV Pipe w washer 3 Wall attach bracket 1 2 7 4 3 6 9 5 8 4 Outdoor sensor...

Page 11: ...wall and there is potential for snow accumulation in the local area both terminals must be installed at an appropriate level above grade or the maximum expected snow line The dimensions and requiremen...

Page 12: ...n in Inches and centimeters 3 4 8 1 cm 40 6 cm 16 A Concentric 1 43 2 cm 17 B Overall Width 2 Exhaust and 2 Air Inlet 19 6 cm 7 3 4 Bolts Anchors 4 provided by installer each is to be suitable for 160...

Page 13: ...e of PVC CPVC vent materials the installer must use proper adhesive to join CPVC and or PVC pipe and fittings 3 1 Combustion Air Mascot LX boilers and water heaters must have provisions for combustion...

Page 14: ...9 3 1 2 Ducted Combustion Air The combustion air can be taken through the wall or through the roof When taken from the wall it must be taken from out of doors by means of the LAARS horizontal wall ter...

Page 15: ...A B149 1 CSAB149 2 and ULC S636 Failure to follow this manual and applicable codes may lead to property damage severe injury or death INSTALLATIONS IN CANADA require the use of venting material certif...

Page 16: ...not allowed Trade Names Models x xx and xxxx refer to variations in nominal size See manufacturer s catalog for a particular application These manufacturers samples have been tested and authorized to...

Page 17: ...n accordance with ANSI Z223 1 NFPA 54 and applicable local codes In Canada the installation must be in accordance with CSA B149 1 or 2 and local applicable codes Consider the following when installing...

Page 18: ...t 91 cm J Clearance to nonmechanical air supply Direct vent only 12 30cm 80 285 36 91cm inlet to building or the combustion air inlet 399 850 Other than Direct vent 4 ft 1 2m below 36 inches 91 cm to...

Page 19: ...stalled In addition the installing plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling...

Page 20: ...raccord s au syst me d vacuation ne fonctionnent pas 1 Sceller toutes les ouvertures non utilis es du syst me d vacuation 2 Inspecter de fa on visuelle le syst me d vacuation pour d terminer la gross...

Page 21: ...ominal Pipe Size Natural Gas SECTION 4 Gas Supply and Piping 4 1 Gas Supply and Piping Gas piping should be supported by suitable hangers or floor stands not the appliance Review the following instruc...

Page 22: ...0 39 Temp Rise F Inlet Temp F Temp Rise F Inlet Temp F Temp Rise F Inlet Temp F 125 150 175 SECTION 6 Water Connections 6 1 Central Heat System Piping NOTE This appliance must be installed in a closed...

Page 23: ...or The pump is sized for a maximum of 30 feet 9 1m of piping and the headloss of the boiler only The system designer should take into account allowable boiler temperature rise of 65 F 36 C Maximum 6 2...

Page 24: ...acturer s responsibility Contact Laars to order Kit A2123601 __________________________________________________________________________________________ Figure 13 DHW Connections with Anti Scald Valve...

Page 25: ...piping required by local code must be installed CAUTION Scalding Risk Laars recommends the use of a thermostatic mixing valve at domestic hot water outlet boiler location to reduce potential for scal...

Page 26: ...15 Hydronic Piping only with an indirect tank as a zone Heating Supply Air Eliminator Sediment trap 1 piping to DHW Indirect DWH Tank 18 heat trap Expansion tank and auto feed Heating Return Closely s...

Page 27: ...ltiple baseboard zones Zones with zone valves 24V balancing valves Air seperator DHW 1 1 4 Primary loop Multi Mascot LXs for Large house residential with long muliple baseboard zones Closely spaced te...

Page 28: ...ge homes with long multiple radiant zones Zones with zone valves 24V balancing valves 1 1 4 Primary loop Closely spaced tee s 4 pipe diameters apart Purge drain valves Note Expansion tank may be requi...

Page 29: ...ced tee s 4 pipe diameters apart Increase from 3 4 to 1 1 4 Manifold size based on number of zones required Manifold size based on number of zones required Mascot LX Combi Hydronic piping Heating zone...

Page 30: ...d on number of zones required Manifold size based on number of zones required Mascot LX Combi Hydronic piping Heating zones piped with Zone valves Expansion tank air vent Purge drain valves DHW 1 1 4...

Page 31: ...lectrical outlet with 15A circuit protection FLA is 2A There is an internal 10A breaker to protect internal system components 7 2 Pump Connections Mascot LXC energizes boiler pump opens 3 way valve an...

Page 32: ...F1 5A 5A F2 X3 12 BOILER PUMP R R SYSTEM PUMP X3 7 X3 6 RELAY DHW PUMP RELAY PWB 4 PWB 6 PWB 8 X3 15 PWB 9 X3 14 PWB 7 X3 5 X3 13 PWB 5 RK WIRE X3 8 USED ON LABEL H2365 CD 5 2 1 JM 5 22 14 C GRAPHIC C...

Page 33: ...ze Low Voltage Field Connections located on the front of the inside lower panel OUTDOOR SENSOR SYSTEM SENSOR TANK AQUASTAT DHW SENSOR DC OUT DC IN GROUND GND MOD BUS SAFETY INTERLOCK T T 1 2 3 4 5 6 7...

Page 34: ...ANK NEUT NEUT NEUT LINE LINE LINE INTERLK T FIELD T GROUND 2 1 2 1 4 2 BL 1 4 8 5 SENSOR OUTDOOR L1 IN NEUTRAL GROUND SYSTEM R W V V V BK G FROM X5 BR TO FROM X3 GY BL GY O R BK Y BL W 1 GY W R R BK 1...

Page 35: ...to domestic hot water The control is setup using the User Interface which contains 5 buttons and a digital display Figure 23 The User Interface The User Interface is located on the one panel of the M...

Page 36: ...e set point 5 Icon 1 displays the flue temperature when Darkened 6 Icon 1 displays inlet temperature when arrow up is Darkened outlet temperature when arrow down is Darkened differential outlet inlet...

Page 37: ...l Set is displayed Use the Arrows to adjust to the desired Outlet temperature and then press Select to Save 45 189 130 Inlet Temp Inlet Temperature is displayed as well as the darkened arrow pointing...

Page 38: ...0O P34 On hysteresis Voltage 5 VDC shows 50 V010H P35 BMS Rate at Minimum Voltage 20 shows 200 V010A P36 BMS Rate at Maximum Voltage 100 shows 1000 V010B P37 BMS Temperature Setpoint at Minimum Voltag...

Page 39: ...ressing and holding the Select OK button and Up Arrow simultaneously for five seconds With an active call for heat the boiler will light and run at 100 of firing rate The boilers input can be adjusted...

Page 40: ...process consists of a prepurge trial for ignition and run period The prepurge period starts once the fan RPM reaches a preset level The trial for ignition period follows The trial for ignition period...

Page 41: ...oor Air Shutdown Differential 9 5 Domestic Hot Water Demand 9 5 a Combi Boiler DHW For Combi units MLXC DHW demand is triggered by a flow sensor located near the DHW cold water inlet When water begins...

Page 42: ...for Terminal B and GND To configure the control system identify which boiler is going to be the master boiler for the cascade system and navigate to installer parameter P06 Cascade Address Set the add...

Page 43: ...n the Operating Instructions Start Up Shut Down Instruction Decal located on the back of the Top Front Cover and turn on gas and electrical power to appliance SECTION 10 Set Up Instructions 10 1 Filli...

Page 44: ...CO2 is within the range identified see Figure 26 2 Measure the CO2 in the flue products at low fire Mascot LX can be forced to low fire to allow for easier setup Refer to Section 8 for instructions on...

Page 45: ...Table 17 CO2 Range and Pressure Settings Figure 26 Adjustment Screws and Settings for CO2 Manifold Pressure Screw under cap High fire setting Adjustment Screws on Gas Valve Close door first before me...

Page 46: ...c items listed below every year a Appliance control f Flow switch b Automatic gas valve g Low water cutoff c Pressure switches h Burner d Blower i Heat exchanger e Pump 11 2 1 Burner Check the burner...

Page 47: ...lts from the burner door blower arm If the fan is determined to be defective replace the existing fan with a new one reversing the steps above Make sure to install all of the required O rings and gask...

Page 48: ...r to sections Figure 26 and Table 17 of this manual for the proper adjusting procedures 7 Close all front covers WARNING Serious injury or death could occur if CO2 levels are not adjusted properly ___...

Page 49: ...e start time is over the unit will be in normal operation Firing rate will modulate based on the heating load via the temperature controller settings and readings 5 When the call for heat is complete...

Page 50: ...nsor drift too high E016 Outlet sensor drift too high E017 Flue sensor error E018 Outlet sensor error E019 Inlet sensor error BLOCKING CODES may reduce input rate heating capacity CODE DESCRIPTION b01...

Page 51: ...Mascot LX Boilers and Water Heaters Page 47...

Page 52: ...ON 13 Replacement Parts 13 1 Exploded Parts Views and their Laars Part Numbers 4 See Figure 31 For blower and combustion parts Figure 30 Parts 12 11 42 43 44 45 13 10 14 46 47 26 40 7 38 39 35 37 41 6...

Page 53: ...022700 VALVE GAS LHX x x x x x x x 2p2000 21 RW2013400 GASKET FLAME SENSOR x x x x x x x 22 W2014200 IGNITOR SPARK x x x x x x x 23 W2014300 SENSOR FLAME x x x x x x x 24 RL2018401 BURNER 50 75 x x 24...

Page 54: ...LAARS Heating Systems Page 50 4 Figure 31 Parts Blowers and Combustion 20 18 15 16 26 24 25 27 22 23 21 19...

Page 55: ...43 500 168 PLUG HEX 1 8 NPT x x x x x x x 44 12H5501 GASKET VENT ADAPTER M2 125 x x x x x x x 45 S2114000 GROMMET x x x x x x x 46 E2334702 SWITCH PRESSURE FAN PROVING x x 46 E2334700 SWITCH PRESSURE...

Page 56: ...Rochester NH 03867 603 335 6300 Fax 603 335 3355 1869 Sismet Road Mississauga Ontario Canada L4W 1W8 905 238 0100 Fax 905 366 0130 www Laars com Litho in U S A Laars Heating Systems 1409 Document 128...

Reviews: