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L4103A,B,C COMBINATION Aquastat ® AND HIGH LIMIT CONTROLLER
M6805
BURNER
MOTOR
OIL PRIMARY
CONTROL
L4103
FLUE
LOW WATER
CUTOFF
GAS VALVE
LIMIT
AQUASTAT®
PRESSURE
CONTROL
PILOTSTAT®
CONTROL
M13139
L4103C
L1
(HOT)
L2
1
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
L1
(HOT)
L2
IGNITION
BURNER
MOTOR
OIL
VALVE
LIMIT
AQUASTAT®
BLACK
ORANGE
WHITE
M6804
R4184
OIL
PRIMARY
CONTROL
2
1
12PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
R8184G MAY BE USED IF T-T TERMINALS ARE JUMPERED.
L4103
INSTALLATION
When Installing this Product…
1. Read these instructions carefully. Failure to follow
instructions can damage the product or cause a
hazardous condition.
2. Check ratings given in the instructions and on the
product to make sure the product is suitable for your
application.
3. Make sure the installer is a trained, experienced service
technician.
4. After completing the installation, use these instructions
to check out the product operation.
CAUTION
Hazardous Voltage.
Can cause electrical shock or equipment damage.
Disconnect power supply before beginning installation.
Do not exceed ratings in the Specifications.
Mounting
The manufacturer provides a tapping for insertion of the
controller sensing element. This tapping is located at a point
where typical water temperature can be measured. Follow the
instructions furnished by the system manufacturer, if
available, or use this procedure:
1. Make sure the burner is turned off.
2. If the system is filled, drain to a point below the tapping.
3. Remove the plug from the tapping. (If no tapping is
provided, prepare one properly sized and threaded at
the selected location.)
4. Install the immersion well in the heater tapping, using a
wrench on the well hex.
5. Mount the L4103 by carefully inserting the sensing
element into the well. See Fig. 2.
6. Fit the case over the outer ridge on the neck of the well
and secure it in place by tightening the clamp screw on
the top of the case.
Fig. 2. Location of L4103A,B in oil-fired water heater.
IMPORTANT
The immersion well must fit the sensing bulb snugly
and the bulb must rest against the bottom of the well.
Bend the tubing, if necessary, to hold the bulb
against the bottom of the well, but do not make a
sharp bend in the tubing. Some models have an
adjustable tubing length that can be pulled out to
3 in. (76 mm), if necessary.
Wiring
CAUTION
Hazardous Voltage.
Can cause electrical shock or equipment damage.
Disconnect power supply before making wiring
connections.
All wiring must comply with applicable codes and ordinances.
Refer to burner manufacturer wiring information, if available.
Fig. 3 shows a typical hookup of the L4103A,B oil-fired
application. Fig. 4 and 5 show L4103C gas-fired applications.
Fig. 3. Typical hookup for L4103A,B
Combination Aquastat® and Limit Controller.
Fig. 4. L4103C Combination Aquastat® and Limit
Controller in low voltage gas applications.
3
60-2344—7
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L4103A,B,C COMBINATION Aquastat ® AND HIGH LIMIT CONTROLLER
LOW WATER
CUTOFF
GAS VALVE
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
PRESSURE
CONTROL
PILOTSTAT®
CONTROL
AQUASTAT®
LIMIT
L4103C
L1
(HOT)
L2
M13140
1
Fig. 5. L4103C Combination Aquastat® and Limit
Controller in line voltage gas applications.
OPERATION
When the water temperature in the water heater drops, the
Aquastat® Temperature Controller switch makes to energize
the control. The burner operates until the water temperature
rises to the setpoint and the temperature controller breaks the
circuit to the oil primary control.
The internal high-limit controller breaks the circuit to the
burner if an overheating condition occurs and the safety
switch locks out.
When the limit breaks on the L4103A,B,C, the oil primary
control must be reset before burner operation can resume.
SETPOINT SCALE
HIGH LIMIT
SWITCH WITH
LEADWIRES
AQUASTAT
®
SWITCH
Fig. 6. Internal view of L4103A,B,C
with leadwires on high limit.
SETPOINT SCALE
M6807
Adjusting
Adjust the control point to agree with the manufacturer
recommendations. To adjust, remove the cover and set the
scale to the desired control point. See Fig. 6 and 7. Limit
setpoint is nonadjustable.
CHECKOUT
Check to make certain that the Aquastat® Controller was
installed and adjusted properly. Put the system into operation
and observe the action of the device through several cycles to
make certain that it provides proper control of the system.
Home and Building Control
Honeywell Inc.
Honeywell Plaza
P.O. Box 524
Minneapolis MN 55408-0524
Honeywell Latin American Region
480 Sawgrass Corporate Parkway
Suite 200
Sunrise FL 33325
Home and Building Control
Honeywell Limited-Honeywell Limitée
155 Gordon Baker Road
North York, Ontario
M2H 3N7
Honeywell Europe S.A.
3 Avenue du Bourget
1140 Brussels
Belgium
HIGH LIMIT
SWITCH WITH
QUICK CONNECT
AQUASTAT
®
SWITCH
Fig. 7. Internal view of L4103A,B,C with
quick connects on high limit.
Honeywell Asia Pacific Inc.
Room 3213-3225
Sun Hung Kai Centre
No. 30 Harbour Road
Wanchai
Hong Kong
M6808
Printed in U.S.A. on recycled
60-2344—7 G.H. Rev. 5-98
60-2344—7 4
paper containing at least 10%
post-consumer paper fibers.
customer.honeywell.com