LAARS HEATING SYSTEMS
Page 2
TABLE OF CONTENTS
SECTION 1.
General Information
1A. Introduction.................................................... 3
1B. Warranty........................................................ 3
1C. Technical Assistance..................................... 3
SECTION 2.
Installation Instructions
2A. General Information....................................... 4
2B. Field Assembly .............................................. 4
2C. Site Location.................................................. 5
2C-1. Installation Information .................................. 5
2C-2. Outdoor Installation (U.S. only) ..................... 5
2C-3. Flooring - Typical Installation ......................... 6
2D. Combustion and Ventilation Air Supply ......... 6
2D-1. Outdoor Air Supply ........................................ 7
2D-2. Indoor Air Supply ........................................... 7
2D-3. Exhaust Fans or Vents .................................. 7
2E. Venting of Combustion Products ................... 7
2E-1. General Information....................................... 7
2E-2. Replacement of Existing Heater .................... 8
2F. Water Flow .................................................... 8
2F-1. Reversible Water Connections ...................... 8
2F-2. Water Chemistry.......................................... 11
2F-3. Freeze Protection ........................................ 11
2F-4 Water Hardness .......................................... 11
2F-5. Pump Requirements.................................... 11
2F-6. Pressure Buildup in Water System .............. 11
2F-7. Pressure Relief Valve .................................. 14
2F-8. Water Pressure ........................................... 14
2F-9. Pump Installation ......................................... 14
2F-10. Storage Tank Installation............................. 14
2F-11. Thermal Circulation of Hot Water in
Cold Water Supply Lines ............................. 15
2G. Gas Supply and Piping ................................ 15
2G-1. General Instructions .................................... 15
2G-2. Special Precautions for Propane Gas ......... 16
2H. Electrical Wiring........................................... 16
2I. Combined Space Heating/Potable
Water Heating Systems............................... 16
2I-1. Combined Space Heating ........................... 16
2I-2. Potable Water Heating ................................ 16
SECTION 3.
Operating Instructions
3A. Normal Operating Sequence ....................... 17
3B. Start-Up Procedure ..................................... 17
3C. Setting the Temperature Controls ............... 17
3D. Adjustment for Minimum Input Rate
(models with modulating gas valve) ............ 20
3E. Hi-Limit Switch Checkout ............................ 20
3F. Shut-Down Procedure ................................. 20
SECTION 4.
Maintenance
4A. General Instructions .................................... 20
4B. Replacement of Gas Controls ..................... 21
4C. Heat Exchanger........................................... 22
4C-1. Inspecting the Heat Exchanger ................... 22
4C-2. Cleaning the Heat Exchanger ..................... 23
SECTION 5.
Troubleshooting
5A. Gas Pressure Tests..................................... 23
5A-1. Checking the Main Line Gas Pressure ........ 23
5A-2. Checking the Manifold
Regulated Gas Pressure ............................. 24
5B. Electrical Troubleshooting ........................... 24
5B-1. Heater Does Not Come On ......................... 24
5B-2. Testing the Transformer .............................. 25
5B-3. Testing the Electrical Power Supply ............ 25
5B-4. Testing the Manual Reset
Hi-Limit Switch............................................. 25
5B-5. Testing the Flow Switch............................... 25
5B-6. Testing the Fusible Link
(Flame roll-out switch) ................................. 26
5B-7. Testing the Fuse.......................................... 26
5B-8. Testing the Ignition Control
(for spark ignition)........................................ 26
5B-9. Testing the Ignition Control
(for standing pilot)........................................ 27
5B-10. Testing the High Voltage Ignition Lead........ 27
5B-11. Testing the Safety Shutoff
(for standing pilot)........................................ 28
5B-12. Testing the Safety Shutoff
(for automatic pilot)...................................... 28
5B-13. Testing the Igniter Electrode........................ 28
5B-14. Testing the Pilot Thermocouple
(for standing pilot)........................................ 28
5B-15. Testing for Pilot burner
(for spark ignition)........................................ 28
5B-16. Testing for Burner Ignition
(for standing pilot)........................................ 29
5B-17. Heater Will Not Shut Off .............................. 29
5B-18. On-Off Main Burner Cycling ........................ 29
5B-19. Testing the Terminal Strip/External
Controls ....................................................... 29
SECTION 6.
Parts List
6A. General Information..................................... 30
6B. Parts List ..................................................... 30
To Next Page
Loading...
