Summary of the content on the page No. 5
Mighty Therm Volume Water Heater Page 5 Figure 2. Typical Heater Installation with Base for Combustible Floors, Example A. Figure 5. Installation on Concrete Blocks or Tile. 12345678901234567890 12345678901234567890 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567890123456789 0 1 234567
Summary of the content on the page No. 6
LAARS HEATING SYSTEMS Page 6 combustion and ventilation air is received from a 2B-1. Combustion Air Supply source outside the building. Please refer to the most 1. The heater location must provide sufficient air recent edition of the National Fuel Gas Code, ANSI supply for proper combustion and ventilation of Z223.1, or in Canada, CGA requirements. the surrounding area as outlined in the latest 3. (a) In the United States: Exhaust Fans or Vents: edition of ANSI standard Z223.1, and any local Any
Summary of the content on the page No. 7
Mighty Therm Volume Water Heater Page 7 maintain clearances and prevent physical damage and separation of joints. 4. Avoid ending heater vents near air conditioning or air supply fans. The fans can pick up exhaust flue products from the heater and return them inside the building, creating a possible health hazard. A minimum of 4 feet horizontal distance must be maintained from electrical meters, gas meters, and relief equipment. 5. Always use double-wall or insulated vent pipe (Type B or equival
Summary of the content on the page No. 8
LAARS HEATING SYSTEMS Page 8 Caution Since some leak test solutions (including soap and water) may cause corrosion or stress cracking, the piping must be rinsed with water after testing, unless it has been determined that the leak test solution is noncorrosive. 2E. Electrical Wiring WARNING The heater must be electrically grounded in Figure 8. T-Fitting Sediment Trap Installation. accordance with the most recent edition of the National Electrical Code, ANSI/NPA 70. In 4. The boiler and its indiv
Summary of the content on the page No. 9
Mighty Therm Volume Water Heater Page 9 Figure 10. Tempering Valve Installation. 2G. Water Expansion When cold water is heated the water expands. If no water is being used during the heat-up period the expanded water will normally back up into the city mains. A water pressure reducing valve installed in the incoming cold water line may act as a check valve and Figure 9. Pressure Relief Valve Location. prevent the expanded water from moving backward. This will cause pressure to rise in the heater
Summary of the content on the page No. 10
LAARS HEATING SYSTEMS Page 10 2H. Pump Performance and Installation Minimum Reservoir Equivalent Pipe 1. The factory provided pump on PW heaters and Model IW Gallons* Size and Length the recommended field provided pump for model VW heaters are sized to provide proper 500 through 850 ...............6.3 ................. 1 1/4" x 100 ft. circulation through the heater and heater-to- 1010 through 1220 .........10.2 ................. 1 1/2" x 100 ft. tank circulation loop (see Figures 11 and 12). If
Summary of the content on the page No. 11
Mighty Therm Volume Water Heater Page 11 With Vertical Tank With Horizontal Tank NOTES: Heavy line indicates Heater to Tank Circulating Loop. Figure 11. Hot Water Supply System (Model VW & PW).
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LAARS HEATING SYSTEMS Page 12 Figure 12. Hot Water Supply System Using Model PW with Dual Tanks, Building Loop Return and Circulating Pump. CAUTION: 1. This piping arrangement is required on split systems to provide constant hot water temperatures. 2. Pipe size and length must conform to the recommendations for each heater model. 3. A loop circulator is required to maintain forced circulation in the building hot water piping system. Figure 13. Split System Piping Diagram, Model IW.
Summary of the content on the page No. 13
Mighty Therm Volume Water Heater Page 13 NOTES: 1. All water connections 2" N.P.T. models. 2. Drain valve per ASME requirements. 3. A loop circulator is required to maintain forced circulation in the building hot water piping system. Figure 14. Dual Installation Piping Diagram, Model IW. NOTES: 1. All water connections 2" N.P.T. models. 2. Drain valve per ASME requirements. 3. A loop circulator is required to maintain forced circulation in the building hot water piping system. Figure 15. Single
Summary of the content on the page No. 14
LAARS HEATING SYSTEMS Page 14 With Horizontal Tank Legend B - Check Valve in Hot Water Supply to Tempering Valve C - Check Valve in Return Line from Building Loop D - Tempering Valve E - Venturi (Suction) Tee H - Throttling Valves in Building Loop Returns I - Circulating Pump for 180° Building Loop J - Circulating Pump for 140° Building Loop K - Service Valves to Isolate Heater and Pump for Service With Vertical Tank Legend B - Check Valve in Hot Water Supply to Tempering Valve C - Check Valve i
Summary of the content on the page No. 15
Mighty Therm Volume Water Heater Page 15 Legend B - Check Valve C - Check Valve D - Tempering Valve H - Throttling Valves in Building Loop Returns J - Circulating Pump for Return Loop K - Service Valves to Isolate Heater and Pump for Service Figure 17. Two-Temperature Hot Water Supply System with Vertical Tank for Models VW and PW Water Heaters.
Summary of the content on the page No. 16
LAARS HEATING SYSTEMS Page 16 2J. Tank Installation Flow Head* Temp. Rise Water Rate Loss Across 1. Be sure the floor is waterproof and structurally Model Category (GPM) (ft.) Heater, (°F) capable of supporting the tank when it is filled with water. Soft 45 5.0 17 2. The tank should be placed so that manholes, 500 Normal 68 9.9 11 Hard 90 15.7 8 inspection covers, nameplates and drain valves are accessible
Summary of the content on the page No. 17
Mighty Therm Volume Water Heater Page 17 proven to be lit. Whenever the pilot flame is Dial No. 1234 5678 9+ interrupted, the main gas valve closes within 0.8 seconds. Temp °F 120 128 135 143 150 158 165 173 180+ b. Electronically Supervised Standing Pilot System (System #16): Table 5. Modu-Snap Temperature Settings. When pilot flame fails, the ignition control module responds in less than 0.8 seconds provided. The temperature sensing bulb of the and provides 100% safety shutdown. switch is alwa
Summary of the content on the page No. 18
LAARS HEATING SYSTEMS Page 18 gas supply, the automatic safety shutoff devices must be checked. 1. Before beginning the tests, make sure the main manual gas valve, and any other heater firing valves are in the “OFF” position. 2. Make sure the heater’s power switch is in the “ON” position. After placing the manual pilot gas valve in the open position and resetting all safety devices, (high limit, pressure switch, low- water cutoff, etc.) pilot(s) can be lit following the procedure located on the
Summary of the content on the page No. 19
Mighty Therm Volume Water Heater Page 19 depressed for one minute then release. Once the pilot is lit, the power is supplied through the aquastat to the main gas valve. 2. To set the temperature and high-limit controls: When using a tank aquastat: Set the tank aquastat to the desired tank Figure 21. Main Burner Flame Pattern. temperature. Set the heater temperature control 20°F higher than tank aquastat. Set the manual reset high appearance of “sooting” tips, check for debris limit 50°F high
Summary of the content on the page No. 20
LAARS HEATING SYSTEMS Page 20 Lower the front of the burner (to avoid damaging b. Multi-meter with the following ranges: pilot shield) then remove the burner tray. 0 to 500 volts A.C. 0 to 1000 ohms continuity. c. Tube cleaning kit consisting of reamer, Caution stainless steel brush, speed handle and Black carbon or green soot on a dirty heat handle extensions. exchanger can, under certain conditions, be d. Heater thermometer (with 1/2" NPT well) ignited by a random spark or open flame. To 100-2
Summary of the content on the page No. 1
Installation and Operation Instructions Document 2040D
Installation and Operation
Instructions for
Mighty Therm
Volume Water Heaters
Models VW, PW and IW
Sizes 500-1825
These instructions are to be stored in the pocket provided on the boiler.
FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician,
qualified in hot water heater installation and maintenance. Improper installation and/or operation could
create carbon monoxide gas in flue gases which could
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LAARS HEATING SYSTEMS Page 2 TABLE OF CONTENTS 3C. To Start Up System .................................... 18 SECTION 1. 3D. To Turn Off Heater ....................................... 19 General Information 3E. To Shut Down System ................................ 19 1A. Introduction................................................... 3 1B. Heater Identification ..................................... 3 SECTION 4. 1C. Flow Requirements ...................................... 4 Maintenance 1D. Water C
Summary of the content on the page No. 3
Mighty Therm Volume Water Heater Page 3 1B. Heater Identification SECTION 1. Consult rating plate on the heater. The following General Information example simplifies the heater identification. 1A. Introduction 1 2 345 6 This manual provides information for the PW 1670 I N 09 C installation and operation of Laars volume water heaters. It is strongly recommended that all application 1. Basic heater model.* and installation procedures be reviewed completely 2. Input rate X 1000 BTU/hr. before proce
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LAARS HEATING SYSTEMS Page 4 1C. Flow Requirements SECTION 2. For proper operation, all low volume hot water Installation heaters must have continuous flow through the heat exchanger when firing. The system pump must be 2A. Heater Placement capable of developing sufficient pressure to overcome The heater must be placed to provide specific the resistance of the heater plus the entire circulating clearances on all sides for maintenance and inspection. system at the designed flow rate. There must a
