Installation and Operation Instructions Document 1211F Installation and Operation Instructions for Mighty Therm2 ® Hydronic Boiler Model MT2H Volume Water Heater Model MT2V Sizes 500–2000 MBTU/h FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician, qualified in hot water boiler 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.
LAARS Heating Systems Page 2 TABLE OF CONTENTS SECTION 1. General Information 1.1 1.2 1.3 1.4 1.5 1.6 Introduction.......................................................... 3 Model Identification.............................................. 3 Warranty.............................................................. 4 Dimensions.......................................................... 4 Locating the Appliance........................................
Mighty Therm2 Page 3 SECTION 1. General Information 1.1 Introduction This manual provides information necessary for the installation, operation, and maintenance of Laars Heating Systems Mighty Therm2 copper tube appliances. Read it carefully before installation. All application and installation procedures should be reviewed completely before proceeding with the installation. Consult the Laars Heating Systems factory, or local factory representative, with any issues or questions regarding this equipment.
LAARS Heating Systems Page 4 1.2 Model Identification Consult the rating plate on the unit. The following information describes the model number structure.
Mighty Therm2 Page 5 Unit Size A B C D E Air Conn. W Vent Conn.
LAARS Heating Systems Page 6 Size A B C D E F 500 33¾ 86 16¾ 43 6½ 17 10 25 750 45¾ 116 22¾ 58 6½ 17 1000 57¾ 147 28¾ 73 6½ 1250 68¼ 173 34¼ 1500 78¾ 200 1750 89¼ 227 2000 99¾ 253 8 Air Conn. W Vent Conn.
Mighty Therm2 1.7 Locating Pump-Mounted Boiler with Respect to Return/Supply Header For the best results, a pump-mounted Mighty Therm2 Boiler should be located within 15 feet (4.6m) of the supply and return headers. The pump is sized for 30 feet (9.1m) of piping. If the appliance must be installed with longer piping runs, then larger diameter tubing shall be used. Consult the factory for assistance. 1.
LAARS Heating Systems Page 8 (see Figure 3). Use single-wall galvanized pipe, per Table 4, for the combustion air intake (see Table 2 for appropriate size). Route the intake to the heater as directly as possible. Seal all joints with tape. Provide adequate hangers. The unit must not support the weight of the combustion air intake pipe. Maximum linear pipe length allowed is 50 feet (15.2m). Three elbows have been calculated into the 50-foot (15.2m) linear run. Subtract 10 allowable linear feet (3.
Mighty Therm2 Page 9 enclosed spaces containing combustion appliances. Mighty Therm2 units are not allowed to be vented into a common horizontal vent system, unless a properly sized vent fan is used, and the common vent system is properly designed by the vent fan manufacturer or a qualified engineer. Refer to the installation and operating instructions on all appliances to be common vented for instructions, warnings, restrictions and safety requirements.
Page 10 U.S. Installations (see note 1) A= Clearance above grade, veranda, porch, 12 inches (30 cm) deck, or balcony B= Clearance to window or door that may be 4 feet (1.
Mighty Therm2 Personal injury or DEATH may occur. Natural snowfall, drifting, and banking should all be taken into account when locating the terminals in a potential snow environment. 4. If the Mighty Therm2 is side-wall vented to the same wall, locate the vent terminal at least 3 feet (0.9m) horizontally from the combustion air terminal, and locate the vent terminal at least 1 foot (0.3m) above the combustion air terminal (see Figure 4). Page 11 4. (b) 1. 2.3.
LAARS Heating Systems Page 12 remaining connected to it. At the time of removal of an existing boiler, the following steps shall be followed with each appliance remaining connected to the common venting system placed in operation, while the other appliances remaining connected to the common venting system are not in operation. 1. Seal any unused openings in the common venting system. 2.
Mighty Therm2 galvanized pipe and elbows to allow the open end to face down aside the boiler. This is available as a Commercial Kit from the manufacturer. Part numbers for the low profile terminals to cover the vent and combustion air openings are shown in Table 6. Section 3. Gas Supply and Piping 3.1 Gas Supply and Piping Gas piping should be supported by suitable hangers or floor stands, not by the appliance.
Page 14 Section 4A. Water Connections — Boiler 4A.1 Heating System Piping: Hot Supply Connections — Boiler NOTE: This appliance must be installed in a closed pressure system with a minimum of 12 psi (82.7kPa) static pressure at the boiler. Hot water piping should be supported by suitable hangers or floor stands. Do not support piping with this appliance. Due to expansion and contraction of copper pipe, consideration should be given to the type of hangers used.
Mighty Therm2 The Mighty Therm2 can be used with several different types of readily available storage tanks. A pump draws water from the storage tank and pumps the water through the heater and back into the tank. Pump-mounted units have a circulating pump built into the water heater. The pumps used are sized for the headloss through the heater, plus 30 feet (9.1m) of full-sized piping (same size as boiler outlet) and a normal number of fittings.
Page 16 Figure 6. Hydronic Piping — Multiple Boilers, Primary Secondary System. Figure 7. Hydronic Piping — Multiple Boilers, Low Temperature System.
Mighty Therm2 Figure 8. Hydronic Piping — One Boiler, Multi-Temperature System. Figure 9. Hydronic Piping - Primary-Secondary, Reverse-Return.
Page 18 Figure 10. Hydronic Piping - Primary-Secondary, Reverse-Return, Low Temperature. Figure 11. Water Heater Piping — One Heater, One Tank.
Mighty Therm2 Figure 12. Water Heater Piping — Multiple Heaters, One Tank. Figure 13. Water Heater Piping — One Heater, Multiple Tanks.
LAARS Heating Systems Page 20 Figure 14. Water Heater Piping — Multiple Heaters, Multiple Tanks. Unit gpm ft Temp Rise °F Size S N H S N H S N 500 45 68 90 1.8 2.3 3.5 19 750 45 68 90 2.1 3.0 6.0 28 lpm m Temp Rise °C H S N H S N H S N H 13 9 170 257 341 0.5 0.7 1.1 10 7 5 19 14 170 257 341 0.6 0.9 1.8 16 10 8 1000 45 68 90 2.3 3.6 6.1 38 25 19 170 257 341 0.6 1.1 1.9 21 14 10 1250 68 68 90 3.8 3.8 6.
Mighty Therm2 Page 21 WARNING The appliance must be electrically grounded in accordance with the requirements of the authority having jurisdiction or, in the absence of such requirements, with the latest edition of the National Electrical Code, ANSI/ NFPA 70, in the U.S. and with latest edition of CSA C22.1 Canadian Electrical Code, Part 1, in Canada. Do not rely on the gas or water piping to ground the metal parts of the boiler. Plastic pipe or dielectric unions may isolate the boiler electrically.
LAARS Heating Systems Page 22 TB1-1 L1 MAIN POWER SWITCH DPDT N1 120 VAC JUMPER HSI #1 IGN BD #1 35 67 L1 IGN BD #1 35 67 S1 IGN BD #2 35 67 L1 IGN BD #2 35 67 S1 IGN BD #1 35 67 S2 IGN BD #1 35 67 L2 IGN BD #2 35 67 S2 IGN BD #2 35 67 L2 HSI #2 BLOWER 1 HIGH K1 K1 LOW BLOWER 2 HIGH K2 K2 LOW PUMP K3 120 VAC 2 1 TO PUMP P1 P2 24 VAC 1 IGN BD #1 35 67 24V IGN BD #1 35 67 F1 IGN BD #1 35 67 F2 35 67 F1 IGN BD #2 35 67 F2 IGN BD #2 LOW GAS 35 67 GND 35 67 IGN 24V BD #2 35 67 G
Mighty Therm2 Figure 19. Mighty Therm2 (500–750) Connection Diagram.
Page 24 Figure 20. Mighty Therm2 (1000) Connection Diagram.
Figure 21. Mighty Therm2 (1250–2000) Connection Diagram.
Page 26 field wire area. Single circuit 120-volt units will be field connected at the main terminal block labeled "120V (L1)", "NEUTRAL" and "GROUND". See Figure 15 for over current protection ratings. Sizes 1750, 2000 (and those which have been field retrofitted to electrically separate the pump and heater) require two 120-volt circuits. The heater circuit is found on the main terminal block and denoted as "120V (L1)", "NEUTRAL" and "GROUND".
Mighty Therm2 If there is a subsequent loss of flame signal, the burner will attempt re-ignition up to three times (only once if optional lockout ignition is used.) When the call for heat is satisfied, the gas valves(s) close and the blowers continues to run for 30 seconds. The pump will continue to run for 0.1 to 10 minutes, depending on what the pump time delay has been set to. Mighty Therm2 sizes 1,000-2,000 have two ignition controls that control the individual stages.
LAARS Heating Systems Page 28 and to replace any part of the control system and any gas control that may have been under water. 6.3 Operating Temperature Control All Mighty Therm2's are equipped with a two-stage aquastat. To utilize this mounted controller be sure to have the "Local/Remote" selector switch to "Local". Set the controller to the desired operating set point. The controller has an interstage differential that can be adjusted from 3°F to 10°F.
Mighty Therm2 No orifice changes are required to adjust the Mighty Therm2 appliances for high altitude. High altitude adjustment is accomplished by adjustment of the gas valve manifold pressure and the air shutter(s). The required instruments used to assist in these adjustments are a CO2 or O2 Analyzer and a U-Tube Manometer or other device capable of reading a pressure of 2.5-3.0 inches W.C. (0.62-0.75 kPa). Start the adjustment process by checking the CO2 in the “as installed” condition.
Page 30 Only genuine Laars replacement parts should be used. Caution Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dan-gerous operation. Verify proper operation after servicing. See Figure 5 for location of gas train components. The gas and electric controls on the appliance are engineered for long life and dependable operation, but the safety of the equipment depends on their proper functioning.
Mighty Therm2 7.2.8 Transformer The transformer is not capable of supplying control voltage for external devices such as zone valves, which must have their own separate power supply. Should a transformer need replacing, shut off the 120-volt power. Unplug the transformer wires, remove the mounting screws and remove the transformer. Replace transformer in the reverse order. 7.2.9 Blowers The combustion air blowers bring the combustion air for the Mighty Therm2 from the upper chamber to the lower chamber.
Page 32 Section 8. Trouble Shooting 8.1 Resolving Lockouts There are many causes of lockouts. The three most common causes are: (1) inadequate gas supply, (2) poor combustion, (3) ignitor failure. 1. Inadequate gas supply: Before proceeding, ensure that the gas supply has not been shutoff or the LP tank (LP boilers) is not empty. Then, restart the boiler and observe the operational cycle. After a 15-second fan pre-purge, the ignitor will heat up for 20 seconds, and then the unit will light.
Size 750 Size 1000 Size 1250 Size 1500 Size 1750 Size 2000 (1) 5F3015 5F3016 5F3304 (2) (1) 5F3015 5F3016 5F3304 (2) (2) 5F3015 5F3016 10F3304 (1) (2) 5F3015 5F3016 20F3304 (2) (2) 5F3015 5F3016 20F3304 (2) (2) 5F3015 5F3016 20F3304 (2) (2) 5F3015 5F3016 20F3304 (2) 5F3320 7F3320 10F3320 12F3320 15F3320 17F3320 20F3320 5F3420 5F3420 5F3420 5F3420 5F3420 5F3420 5F3420 5F3421 5F3421 5F3421 5F3421 5F3421 5F3421 5F3421 5F3520 5F3520 5F3520 5F3520 5F3520 5F3520 5F3520 5F3521 5F352
Size 500 Size 750 Size 1000 Size 1250 Size 1500 Size 1750 Size 2000 Assembly, Copper Tube, Heat Exchanger 5C4000 7C4000 10C4000 12C4000 15C4000 17C4000 20C4000 Assembly, Cupro-Nickel, Heat Exchanger 5C4020 7C4020 10C4020 12C4020 15C4020 17C4020 20C4020 33 Tile, Side (Left and Right) T2015600 T2015600 T2015600 T2015600 T2015600 T2015600 T2015600 (2) (2) (2) (2) (2) (2) (2) 34 Tile, Front T2017300 35 Tile, Front, Left Side T2016200 T2016800 T2016800 T2016800 T2016800 T2016800 T2016800 36 Tile,
Size 500 Size 750 Size 1000 Size 1250 (24) L2012400 (24) (3) L2013000 (21) L2012400 (21) S2012700 (3) L2013000 (18) L2012400 (18) S2012700 (3) 2400-286 (2) (3) 2400-286 (2) (2) 2400-286 (4) L2013000 (3) L2012500 (2) L2012500 (3) (2) L2012500 (1) L2012200 (1) L2012200 S2012500 (2) L2012200 (2) L2012700 (2) L2012700 (2) (4) L2012700 (1) L2012600 L2012600 S2012500 L2012600 L2012900 Size 2000 (1) Size 1750 L2012900 Size 1500 58 59 60 62 Heat Exchanger Compo
Baffle, Water Deflector, Inlet Well, Immersion, Temperature Control Cover, Return, Glass-Lined Cast Iron Cover, Return, Bronze Pump Housing, Glass-Lined Cast Iron Baffle, Diffuser, Pump Housing Inlet 10338300 E2058300 10364300 10364301 S2056900 10338400 Size 500 10338300 E2058300 10364300 10364301 S2056900 10338400 Size 750 10338300 E2058300 10364300 10364301 S2056900 10338400 Size 1000 10338300 E2058300 10364300 10364301 S2056900 10338400 Size 1250 10338300 E2058300 10364300 10364301 S2056900 1033
Mighty Therm2 Figure 23. Sheet Metal Components.
Page 38 Figure 24.
Mighty Therm2 Page 39 Mighty Therm2 Water Heater Mighty Therm2 Hydronic Boiler Size Pump p/n 500 A2001700 Size 500 Pump p/n Soft Water Normal Water Hard Water A2001700 A2001700 A2001900 750 A2001700 750 A2001700 A2001700 A2001900 1000 A2001800 1000 A2001700 A2001800 A2001900 1250 A2001800 1250 A2001700 A2001800 A2001900 1500 A2001900 1500 A2001700 A2001900 A2001900 1750 A2001900 1750 A2001900 A2001900 A2001900 2000 A2109700 2000 A2109700 A2109700 A2109700
LAARS Heating Systems Page 40 H2329100F Figure 26. Electrical Components. Laars Heating Systems Company reserves the right to change specifications, components, features, or to discontinue products without notice. 800.900.9276 • Fax 800.559.1583 (Customer Service, Service Advisors) 20 Industrial Way, Rochester, NH 03867 • 603.335.6300 • Fax 603.335.3355 (Applications Engineering) 1869 Sismet Road, Mississauga, Ontario, Canada L4W 1W8 • 905.238.0100 • Fax 905.366.0130 www.Laars.com Litho in U.S.A.