Laars Rheos RHCH, Installation And Operation Instructions Manual

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LAARS Heating Systems
Page 2
TABLE OF CONTENTS
SECTION 1.
General Information
1.1 Introduction ........................................................ 3
1.2 Model Identification ............................................ 3
1.3 Warranty ............................................................ 4
1.4 Dimensions ........................................................ 4
1.5 Outdoor Installations .......................................... 6
1.6 Locating the Appliance ....................................... 6
1.7 Locating Pump-Mounted Water
Heater with Respect to Storage Tank(s) ............ 6
1.8 Locating Pump-Mounted Boiler with
Respect to Return/Supply Header ..................... 6
1.9 Locating Appliance for Correct Vent Distance
From Outside Wall or Roof Termination ............. 6
SECTION 2.
Venting and Combustion Air
2.1 Combustion Air .................................................. 7
2.1.1 Combustion Air From Room .............................. 7
2.1.2 Intake Combustion Air ........................................ 7
2.2 Venting ............................................................... 9
2.3 Locating Vent & Combustion Air Terminals ........ 9
2.3.1 Side Wall Vent Terminal ..................................... 9
2.3.2 Side Wall Combustion Air Terminal ...................11
2.3.3 Vertical Vent Terminal .......................................11
2.3.4 Vertical Combustion Air Terminal ..................... 15
2.4 Common Vent Test – Boilers ............................ 15
SECTION 3.
Gas Supply and Piping
3.1 Gas Supply and Piping .................................... 15
SECTION 4A.
Water Connections – Rheos Boiler
4A.1 Heating System Piping:
Hot Supply Connections – Boiler ..................... 18
4A.2 Cold Water Make-Up – Boiler .......................... 18
4A.3 Water Flow Requirements – Boiler .................. 18
4A.4 Freeze Protection – Boiler ............................... 19
SECTION 4B.
Water Connections – Rheos Water Heater
4B.1 Water System Piping – Water Heater .............. 19
4B.2 Hot Water Supply Piping – Water Heater ......... 19
4B.3 Water Flow Requirements – Water Heater ...... 20
4B.4 Combined Water (potable)
Heating and Space Heating ............................. 20
4B.5 Freeze Protection — Water Heater .................. 20
SECTION 5.
Electrical Connections
5.1 Main Power ...................................................... 21
5.2 Pump Connections .......................................... 21
5.3 Temperature Control – Boiler ........................... 21
5.4 Temperature Control – Water Heater ............... 21
5.4.1 Remote Water Heater Temperature Control .... 21
5.4.2 Internal Water Heater Temperature Control ..... 22
5.5 Temperature Control Features ......................... 22
5.5.1 Temperature Setpoint ...................................... 24
5.5.2 Differential Setting ............................................ 24
5.5.3 Offset ............................................................... 24
5.5.4 Throttling Range .............................................. 24
5.5.5 Minimum Output Setting .................................. 24
5.5.6 Integration Constant ........................................ 24
5.6 External Control Connections .......................... 25
5.7 Wiring Diagrams .............................................. 25
SECTION 6.
Operating Instructions
6.1 Filling the Boiler System .................................. 38
6.2 Operating the Burner and Set Up .................... 38
6.3 Shutting Down the Rheos ................................ 40
6.4 To Restart the Rheos ....................................... 40
SECTION 7.
Maintenance
7.1 System Maintenance ....................................... 40
7.2 Appliance Maintenance and
Component Description ................................... 40
7.2.1 Burner .............................................................. 41
7.2.2 Filter ................................................................. 41
7.2.3 Modulating Gas Valve ...................................... 41
7.2.4 Safety Gas Valve ............................................. 41
7.2.5 Manual Reset High Limit Control ..................... 41
7.2.6 Temperature Control ........................................ 41
7.2.7 Ignition Control ................................................. 41
7.2.8 Ignitor / Flame Sensor Assembly ..................... 42
7.2.9 Transformers .................................................... 42
7.2.10 Blower............................................................ 42
7.2.11 Flow Switch .................................................... 42
7.2.12 Heat Exchanger Coil...................................... 42
7.2.13 Normally Open Vent Valve ............................. 43
7.2.14 Motorized Safety Valve .................................. 43
7.2.15 Gas Pressure Switches ................................. 44
SECTION 8.
Trouble Shooting
8.1 Sequence of Operation .................................... 45
8.2 Resolving Lockouts .......................................... 45
8.3 Delayed Ignition – Possible Causes ................ 45
8.3.1 High Lockup Pressure (LP Appliances)
- Occurs on Start-up ........................................ 45
8.3.2 Gas Valve Regulation ...................................... 45
8.3.3 Defective Burner - Occurs on
Startup or at Burner Shutdown ........................ 46
8.4 Short Cycling – Boiler ...................................... 46
8.5 Short Cycling – Water Heater .......................... 46
8.6 High Gas Consumption .................................... 46
SECTION 9.
Replacement Parts
9.1 General Information ......................................... 46
9.2 Parts List .......................................................... 47
Tables Listing
................................................................. 56
Figures Listing
.............................................................. 56