Crown Boiler 24-08, 24-11, 24-10, 24-12, 24-06, 24-05, 24-09, 24-03, 24-04, 24-07 Mechanical

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A2. 3-way RTC in Primary/Secondary – Heating and DHW using Tankless Coils; with/without Outdoor Reset

(MECHANICAL)

72

NOTES:

1)Install the boiler as indicated above for systems where return temperatures may be less than 135F and heating/DHW with tankless coils.

2)The Outdoor Sensor (S3) and the Mix Supply Sensor (S2) are required when the Outdoor Reset feature is selected. The mix sensor must be installed 10 pipe diameters downstream of the system pump, in the primary loop. The mix sensor must be secured to the surface of the pipe using a wire tie or similar device.

3)The by-pass piping, diverting valve and boiler circulator must be sized using the sizing charts found in Appendix B.

4)Closely spaced tees must connect the branch to the larger header. The Tee centerlines must be no greater than 4 times the larger header pipe diameter.

5)The diverting valve, V1, must be no greater than 11 linear feet of pipe from the Return Sensor, S1.

6)There shall be a MINIMUM of 4 linear feet of pipe between the By-pass Mix Point, M1, and the Return Sensor, S1.

7)The balancing valve in the boiler return line, V2, may be necessary in low head by-pass loop applications.

8)Domestic Hot Water must be tempered for safe usage. The tankless aquastat and/or a storage tank aquastat (A1) are normally closed switches. Circuit breaks on temperature rise.

9)Expansion tanks, air scoops and other components left out for clarity.

10)Observe all applicable plumbing and electrical codes.

This diagram is for reference only. The installer or designer is responsible for the proper selection and design of the system.

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Contents Series Page Important Information Read Carefully Page Page Table of Contents Table of Contents Section I General Information Boiler RATINGS/DATA Section I General Information Locate the UnitBoiler Foundation Chimney or VentVents Faults & Suggestions Section II Cast Iron Block Assembly Assembly of Sections Manual DRAW- UPNipple Gauge Series 24 Section Arrangement Draw-Up Rods Alternating Pattern Manual Draw-up Center Section Channel Block Position Partial Block Draw-Up Hydraulic Draw-Up of Sections Section III Installation Instructions Canopy with Rear Flue Outlet Damper AssemblyBare Boiler Assembly Avoid Breathing Fiber Particulates and Dust Left Side Canopy Intermediate Bracket Mount Rear Observation Port Cover Refer to Figure Inspect ALL Boiler SealsSeries 24 Jacket Assembly Boiler Models 24-03 thru Burner Mounting Plate Refer to Figures 16 Mount Burner Adapter Plate to Burner Mounting PlatePurpose of Tappings Steam Boilers Steam Trim Steam Boilers Install Steam Trim This Is Intentionally Left Blank Purpose of Tappings Water Boilers Water Trim Water Boilers Install Water Trim Burner InstallationBoiler Piping Heating Applications Page Parallel Piping Conversion Recommendation 1 Use when Recommendation 2 Use when Recommendation 3 Use when Page Page Page BMounting Elevations M&M 150, 64 Float Low Water Cut-offs Schematic Tankless Heater Piping 24-08 24-09 Return Temperature Control and Components CCW Open to SystemWater Boiler Pressure Relief Valve Hook-Up Typical Boiler Wiring with RTC Front Typical Boiler with RTC Return Sensor Rear Always Inspect Installation Before Section IV Operating InstructionsStarting Burner Fill Heating System with WaterFlame Failure Boil MIN Delay Test Controls Check Operation of High Limit ControlBoiler and System Cleaning Steam Boiler Boiler and System Cleaning Water Boilers Frequent Water Addition Oxygen CorrosionSection V Service Instructions Clean the Boiler FluewaysMaintenance of LOW Water Cutoff Devices General Maintenance Considerations OperationSection VI Burner Specifications OIL BurnersSection VII Repair Parts & Carton Contents Series 24 Master Parts List Section VII Repair Parts Jacket Carton Bare Boiler Assembly Section Joiner Carton Assy Rear Target Wall Carton Standard Steam Trim Carton Assy RTC Carton with Outdoor Reset Tankless Coil Components Boiler Water Section Viii Appendix Page Mechanical Page Mechanical Electrical Page Page Page Page Page Page Page Page Series 24 Boiler Circulator Selection Taco 20F Differential Boiler Recirculation Grundfos Circulating Pump Way Boiler Recirculation Bell and Gossett Circulating Pump Way Boiler Recirculation Armstrong Circulating Pump Way Appendix C Valve and Actuator Mounting Instructions ApplicationService Record PN 980417 S24 12/05