Honeywell L6006A Aquastat Information
Buy, replace, install, set-up, & wire the L6006A aquastat control
AQUASTAT L6006A HONEYWELL GUIDE - CONTENTS: Guide to the functions of the Honeywell L6006A heating boiler combination control aquasta, L6006A aquastat iInstallation manuals. Guide to the Honeywell 6006 Single Function Boiler Limit Control, How to set the HI LO and DIFF on a heating boiler control.
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Guide to aquastat controls on heating equipment:
This article series explains how aquastats work and what the different aquastat controls are, what they do, and how they are set. We define the HI LO and DIFF controls on heating boiler aquastats and explains what they do and how they work. We explain the location and use of the heating boiler reset button found on aquastats.
We discuss relationship among HI, LO, DIFF, and heating burner cut-in, cut-out, and circulator lockout that are provided on the combination control. We explain how the Aquastat controls hot water production via a tankless coil on the heating boiler.
We explain how to disable the LO control when a tankless coil is not in use on a boiler. After explaining the operation of an aquastat's Hi, Lo, and Diff controls we review the newer universal replacement aquastat from Honeywell, the L7224U Universal Aquastat, followed by a discussion of the simpler single-limit control switches.
Reader Question: how to set the large and small dials on the Honeywell L6006A
(Dec 23, 2014) Mark said:
I was looking for a bit more explanation (or perhaps just a layman's explanation) of an aquastat's hi/low/diff functions as it relates to my specific situation.
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My aquastat is the Honeywell L6006A. It has one large dial and one smaller (differential) dial. It is attached downstream from a heat exchanger/air handler unit in my gas-fired hydronic heating system, and the fan is being controlled by the aquastat.
I have the large dial at 160and the differential to 5 degrees.
Does this mean that when the water in the heat exchanger reaches approx 165 the fan should turn-on, and when it cools to approx 155 it should turn-off?
The large dial whose numbers you see when the control cover is on is the HI or HIGH LIMIT - see SETPOINT INDICATING WHEELin Honeywell's illustration adapted at above left
There is a smaller DIFFerential setting dial inside the control - in the illustration at above left see DIFFERENTIAL ADJUSTMENT WHEEL.
The aquastat is monitoring water temperature at the point where its sensor is installed in order to turn the burner on and off.
Click and enlarge the white, green, yellow illustration in the article just above to see how a typical Honeywell control relates the DIFF setting to heat on or off.
Here is what the manufacturer says:
Key is this phrase about the High Limit found below:
Turns on burner at temperature setting, minus differential.
For proper selection of settings, follow the boiler manufacturer recommendations.
Watch out: although it may be marked as "optionl" in some company illustrations, the company also provides and recommends use of a heat-conducting grease when installing the L606A high limit controller into its immersion well on the heating appliance. Without good thermal contact between the temperature sensing bulb [ INSERTION ELEMENT in the illustration above and shown in detail just below] the control may not operate reliably.
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Honeywell L6006A High limit controller
— Shuts off burner when water temperature exceeds high limit setting. Burner restarts
when temperature drops to high limit setting, less
Honeywell L6006A Low limit controller
— Maintains minimum boiler temperature for domestic hot water. Turns on burner at
temperature setting, minus differential.
Honeywell L6006A Circulator controller
— Prevents circulation of water that
is not hot enough. Breaks circulator circuit at temperature setting minus differential; remakes the circuit
when the temperature setting is reached.
Honeywell L6006A Switching action is as follows:
Upon a drop in boiler water temperature (to dial setting,
less differential), makes R to B burner contact; breaks R to W
contact, preventing circulator operation.
Upon a rise in boiler
water temperature (to dial setting), breaks R to B burner
contact, makes R to W circulator contact
Continue reading at AQUASTAT HI LO DIFF SETTINGS that explains the best settings to use & how & when to disable the LOW & DIFF controls or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Thanks to Bottini Fuel service manager Ron Thomas for discussing aquastat functions, low limit controls, oil burner short cycling causes, and boiler maintenance, reliability, and service contracts 4/13/2010. Bottini Fuel is a residential and commercial heating oil distributor and oil heat service company in Wappingers Falls, NY and with offices in other New York locations. Bottini Fuel, 2785 W Main St,
Wappingers Falls NY, 12590-1576
(845) 297-5580 more contact information for Bottini Fuel
Thanks to reader powderfinger5 for careful reading of this text and suggesting clarifications - August 2011
Thanks to reader Gary (Buddy Cat) for careful reading & editing - November 2012
We provide links just below to several aquastat installation, setting, and adjustment documents in response to reader requests and comments that people sometimes have difficulty finding this information. But readers looking for specific aquastat control information should always first try the control manufacturer.
Armstrong 24-hour time and aquastat control accessory: provides on/off pump control according to preset operating times, designed only for use with specified Armstrong Astro series wet roto circulators installed in indoor hot water re circulation applications. Typical timer applications will cycle the pump at preset times, allowing the user to select
operation of the circulating pump during high peak usage periods in order to decrease the
delivery time to outlet fixtures and reduce wasted water, also available at www.honeywell.com
Honeywell Corporation, control installation guides for Honeywell aquastats and other heating and cooling controls: see http://customer.honeywell.com
Honeywell L4008E Aquastat high limit,manual reset, aquastat controller instructions
Honeywell L4006, Manual Reset Strap-On Aquastat (high limit control, 100 to 240 °F) [we consider strap on controls less accurate and reliable than immersion type sensor controls; these were commonly found on older heating boilers including the GE series downfired boilers]
Honeywell L4026B Aquastat control instructions (contact Honeywell Corporation) Here is some basic description of the Honeywell L4026B control, also available at www.honeywell.com
Honeywell L6006 and L6007 Aquastat Controllers, installation instructions for the trained service technician, these controls combine low or high limit and circulator control, with or without an immersion well depending on the control model A,B, C etc., also available at www.honeywell.com
Honeywell L6191 Dual aquastat immersion thermostat, also available at www.honeywell.com
Honeywell L7224 Aquastat Controller, oil electronic controls allowing high limit, high limit differential, low limit, and separate low limit differential settings - set to the specifications of your oil heating equipment manufacturer - 69-1957-1 L7224 Series controls, also available at www.honeywell.com
L7224U1002- is a universal electronic aquastat (replacing over 40 other aquastat models) that provides circulator, burner and boiler temperature control with electronic temperature sensing. The L7224U1002 provides status and diagnostic information through an LED display to enhance the diagnostic process.
In "Run" mode the LED displays the boiler temperature followed by the ambient temperature. Buttons inside the control permit the service tech to scan through the control's settings as well as to change them, much like the functions on a programmable room thermostat. Using the "I" button, the LED display can be cycled through: boiler temperature, high limit, low limit, high differential, low differential, local thermostat status, EnviraCOM thermostat status, Burner status, Circulator status, Zone control, Zone request, Error code, °F/degC.
Five diagnostic LEDs inside the control provide additional diagnostic features, indicating (counterclockwise from upper left) EnviraCOM network active, Thermostat calling for heat, Burner on, Power to zone circulator interrupted (lockout), Circulator powered.
This is a "triple aquastat" providing High, Low, and circulator controls, as well as advanced features permitting electronic configuration and an LED display for diagnostics. This aquastat can provide multiple zone control as well. The L7224U1002 supports Honeywell's EnviraCOM™ communications that permits remote diagnosis as well as OnWatch diagnostics. The low-limit can be disabled for "cold-start" boiler applications such as where no tankless coil is in use.
Eight error codes: 1=sensor fault (check sensor), 2=ECOM fault, check EnviraCOM wiring, 3=Hardware fault, replace the control, 4=B1 fault, check B1 wiring/voltage, 5=Low line voltage, check L1/L2 110VAC, 6=Fuse, check ECOM wires, replace fuse, 7=EEPROM limit and differential settings, restore to desired settings, 8=Repeated B1 fault, (voltage present at B1 when output is turned off); check B1 wiring/voltage
Honeywell link for a powerpoint training session on this aquastat: http://customer.honeywell.com/NR/rdonlyres/5C67D10A-631C-4404-9149-25BA61F5D8BB/4041/L7224UUNIVERSALAQUASTATTrainingModule.ppt
Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
"Residential Hydronic (circulating hot water) Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
"Warm Air Heating Systems". Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
Installation Guide for Residential Hydronic Heating Systems
Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: email@example.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
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