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L7224A,C; L7248A,C,L
Oil and Electric Boiler
Electronic Aquastat
APPLICATION
The L7224A,C and L7248A,C,L 2012 Compliant
®
Electronic Aquastat
Controllers provide electronic
temperature sensing in a UL limit-rated control with a
single sensing probe. The L7224A,C and L7248A,C,L
control the circulator, oil or electric burner or contactor,
and boiler temperature. The L7224/L7248 is "Outdoor
Temperature Reset" ready which is enabled when
connected to the W8735Y1000 wireless or W8735S1000
wired Outdoor Reset Kit. Outdoor Reset with the L7224/
L7248 is intended for all applications except for tankless
coil systems for domestic hot water. Compliance to 2012
DOE regulation ensures efficiency is maximized without
interfering with domestic hot water demand.
The L7224A,C and L7248A,C,L replace the L8124A,
L8124C, L7124A,C, L7148A and L8148A Controllers.
The L7224A,C and L7248A,C,L series controls provide
status and diagnostic information through an LED display
combined with LED lights as well as EnviraCOM™
communications enabled thermostats and diagnostic
tools to enhance the diagnostic process.
L7224/L7248 Aquastat Controllers are intended for use
in residential-type applications.
Operation of this control may delay the burner operation while the residual heat is
circulated out of the boiler.
NOTE: This operation may be different than earlier electronic Aquastat
revisions which did not implement thermal purge.
2012 DOE Compliance and Operation
®
Controllers
INSTALLATION INSTRUCTIONS
IMPORTANT
Use of Outdoor Temperature Reset on a tank-
less coil application requiring a Low Limit setting
will result in reduced system effectiveness and
efficiency.
SPECIFICATIONS
Electrical Ratings:
Voltage: 120 Vac, 60 Hz.
Power: 7 VA maximum at 120 Vac plus external loads.
Thermostat current: 100 mA nominal at 24 Vac.
Burner Relay:
7.4 A at 120 Vac Full Load Amperage (FLA);
44.4 A inrush Locked Rotor Amperage (LRA);
Less Ignition Load: 360 VA.
Circulator Relay:
7.4 A at 120 Vac FLA; 44.4 A inrush LRA.
Zone Controller (ZC): 7.4 A at 120 Vac FLA;
44.4 A inrush LRA.
NOTE: All loads combined cannot exceed 2000 VA.
Environmental Ratings:
Temperature: -30 °F to +150 °F (-34 °C to +66 °C).
Humidity: 0 to 95% relative humidity, noncondensing.
Approvals:
Underwriters Laboratories Inc. Component Recognized.
Canadian Underwriters Laboratories Inc. Component
Recognized.
®
68-0281-16
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Table of Contents
Related Manuals for Honeywell L7224A
Summary of Contents for Honeywell L7224A
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Page 1: Specifications
Electronic Aquastat Controllers provide electronic efficiency. temperature sensing in a UL limit-rated control with a single sensing probe. The L7224A,C and L7248A,C,L SPECIFICATIONS control the circulator, oil or electric burner or contactor, and boiler temperature. The L7224/L7248 is “Outdoor Temperature Reset” ready which is enabled when... -
Page 2: Installation
Part Number (mm) Application Mounting 50001464-001 12 (304.8) Well-mounted controls The L7224A,C and L7248A,C,L models are available in a 50001464-003 24 (609.6) Flush-mounted controls well-mount, horizontal position, vertical position, or flush mounted remote from the well versions. Dimensions for 50001464-004 36 (914.4) -
Page 3: Flush-Mounted Aquastat Replacement
® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS New Installation SENSOR WIRES Order well assemblies separately; see Table 1 and form CONTROLLER CASE no. 68-0040, Immersion Wells and Compression Fittings BOILER for Temperature Controllers. Boilers usually have tappings... -
Page 4: Replacement Sensor Installation
Follow the appropriate wiring diagrams shown on the Turn off all power and: inside of the front cover of the L7224A,C; L7248A,C,L or 1. Carefully disconnect sensor from circuit board by in Fig. 8–13. -
Page 5: Adjusting Settings
Temperature units (°F or °C) parameters. * Settings available for adjustment on the 3-digit display The L7224A,C and L7248A,C,L are designed for use with only if a W8735Y1000 or W8735S1000 Outdoor Reset 24 Vac electronic and electromechanical thermostats or Kit is installed. -
Page 6: High/Low Limit Controller
® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS has not gone below the Low Limit setting (minus the Differential); or, ZR input is not powered with 120 Table 4. Display readout definitions. Vac (only L7248L with ELL set On). -
Page 7: Frost Protection
® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS NOTE: This feature is blocked if a Domestic Hot When the Boiler temperature reaches the Frost Protection Water demand occurs. Domestic Hot Water Limit temperature plus a fixed 10 °F differential, the burner... - Page 8 LINE VOLTAGE OIL BURNER RELAY OUTDOOR RESET MODULE IS OPTIONAL. W8735S1000 WIRED OUTDOOR RESET MODULE SHOWN. FOR BEST PERFORMANCE SET DUU=”ON”. M32023A Fig. 8. L7224A,C; L7248L single heat zone with indirect water tank and circulators. Optional Outdoor Reset Module. 68-0281—16...
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Page 9: Controller Operating Sequence
® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS Table 6. L7224/L7248 Controller Operating Sequence. Action System Response Thermostat calls for heat. Circulator starts when water temperature is above Low Limit setting (if applicable) or above the Thermal Purge Temperature Limit (tPL) if Thermal Purge is enabled. - Page 10 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS Table 8. Controller Operating Sequence with External Low Limit device connected trough the ZR terminal. Action System Response Zone Request (ZR) terminal is connected to Boiler temperature is checked. Burner starts when water temperature L1 (External Low Limit call for heat).
- Page 11 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS Table 11. Troubleshooting Guide System Diagnostic Condition Condition Check Action Boiler is hot, Display is ON. 120 Vac at C1-C2 • 120 Vac at C1-C2, check wiring to pump. house is cold.
- Page 12 DUU MUST BE SET TO “ON” ON THE AQUASTAT. REFER TO DEVICE LABEL FOR WIRE COLOR CODE. VALVE IS OPTIONAL ON SPECIFIED MODELS. M32025B Fig. 10. L7224A,C single zone system with circulator and indirect water tank with EnviraCOM™ thermostat. 68-0281—16...
- Page 13 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS ELL=OFF TO ADDITIONAL R845A ZONE 2 RELAYS FOR OTHER ZONES CIRCULATOR (HOT) L2 R845A RELAY ZONE 2 ZONE 2 LOW VOLTAGE ENVIRACOM THERMOSTAT LOW VOLTAGE TERMINALS THERMOSTAT W8735Y1000 OR W8735S1000...
- Page 14 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS W8735Y1000 OR W8735S1008 W8735S1000 MULTI-ZONE 1 2 3 TS TS 1 2 3 OT OT RELAY PANEL C7089U OUTDOOR SENSOR 32003971-003 TEMPERATURE SENSOR R7184/R7284 (HOT) L2 LIMIT L7224 BURNER ENVIRACOM™...
- Page 15 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS ELL=ON L1 (HOT) L6006 LOW LIMIT CONTROLLER VOLTAGE THERMOSTAT L7248L SENSOR LINE VOLTAGE CIRCULATOR LINE VOLTAGE OIL BURNER RELAY POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED. CONTROL CASE MUST BE CONNECTED TO EARTH GROUND.
- Page 16 ® L7224A,C; L7248A,C,L OIL AND ELECTRIC BOILER ELECTRONIC AQUASTAT CONTROLLERS Automation and Control Solutions Honeywell International Inc. 1985 Douglas Drive North ® U.S. Registered Trademark Golden Valley, MN 55422 © 2013 Honeywell International Inc. 68-0281—16 M.S. Rev. 09-13 customer.honeywell.com Printed in United States...