Honeywell L4006 Installation Manual
95-6120B-05
L4006,L4007 Aquastat Controllers
CAUTION
INSTALLATION INSTRUCTIONS
APPLICATION
These boiler-mounted, immersion type controllers
operate in response to temperature changes in hydronic
heating systems.
L4006A,C; L4007 A break the circuit on a temperature
rise to the control setting. They are used tor high limit or
low limit control. When used as a controller or as a low
limit, a separate high limit must be used.
L4006B, L4007Bmake the circuit on a temperature rise.
They are used as a circulator controller, delaying
circulator operation if boiler water temperature is below
the control setting.
L4006E (horizontal well with vertical option) models
include trip-tree manual reset switch. Whenever the
temperature of the controlled medium reaches the high
limit setting, these models are designed to break the
control circuit. A reset button at the front of the case
must be pressed to re-establish the control circuit.
L4006G includes two switches which break
simultaneously on temperature rise to the control
setting. This model is used tor high limit and circulator
control.
Depending on the model, the Aquastat controllers may
include:
• bulb compression titting (L4006C only),
• immersion well tor mounting vertically, or
• immersion well for mounting horizontally.
INSTALLATION
When Installing this Product...
1. Read these instructions carefully. Failure to follow
them could damage the product or cause a hazardous condition.
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable
for your application.
3. Installer must be a trained, experienced service
technician.
4. After installation is complete, check out product
operation as provided in these instructions.
Disconnect power supply before beginning
installation to prevent electrical shock or
equipment damage.
Mounting
The boiler manufacturer generally provides a tapping for
insertion of the Aqua stat controller's sensing element.
This tapping is located in a representative point where
typical boiler water temperature can be measured.
Depending on model, the element is either inserted in an
immersion well or through a bulb compression fitting.
It immersion well or bulb compression fitting must be
ordered, refer to form 68-0040 “Wells and Fittings for
Temperature Controllers,” for part numbers and ordering
information.
For Models Using an Immersion Well
The well of the Aquastat controller must always be
exposed to average temperature circulating water, and
must never be located close to a hot or cold inlet or
steam coil. Where the tapping is on the side of the boiler,
use an Aquastat controller in which the well can be
mounted horizontally. Where the tapping is on top ot the
boiler, use a model in which the well can be mounted
vertically. Some models include an adapter for vertical
or horizontal mounting. See Fig. 2.
IMPORTANT
Controller may be used with or without immersion well. Well, if used, must fit sensing bulb
snugly tor good thermal response. Bulb should
be inserted until it rests against bottom of well.
then hold it there while tightening the tubing
clamp.
NOTE: Some models have an adjustable tubing length
to 3 in. [716 mm]. In these models, extra tubing
inside the case may be pulled out, if needed.
Follow the mounting instructions furnished by the
system manufacturer if available; otherwise. proceed as
follows.
L4006,L4007 AQUASTAT CONTROLLERS
M38422
VERTICAL MOUNTING
HORIZONTAL MOUNTING
Installing the Immersion Well
On existing installations, shut off the power and remove
the old control. If the old immersion well appears
suitable, and if the adapter clamp on the Aquastat
controller fits the old well spud, this well need not be
replaced.
To install new well:
1. If the system is filled, drain system to a point below
the boiler tapping.
2. Remove old well from boiler tapping.
3. Install the immersion well. Both 1/2 and 3/4 inch x
14 NPT wells are available. Depending on size of
boiler tapping and model ordered, a reducer fitting
may be required.
4. Fill the system. Make sure that the well is screwed
in tightly enough to prevent leakage. Do NOT use
the case as a handle to tighten well after controller
is secured to well.
SETPOINT
INDICATING DIAL
SPST
SWITCH
3
DIFFERENTIAL
ADJUSTMENT
WHEEL
ADAPTER CLAMP
SCREWS
2
1
IMMERSION
WELL
3. Fasten the case of the Aquastat controller to the
well with the adapter clamp. Make certain that the
clamp is properly positioned over the groove of the
well spud. Also be sure the flange at the opening of
the well fits snugly into the opening of the case.
The sensing bulb must bottom in the well for best
temperature response.
MODELS WITH FIXED DIFFERENBTIALS DO NOT INCLUDE
1
ADJUSTING WHEEL.
VERTICALLY MOUNTED IMMERSION WELL IS ATTACHED
2
TO THE BOTTOM OF THE CASE.
3
L4006G INCLUDES TWO SPST SWITCHES.
Fig. 1. Internal view showing L4006 (model with
horizontal well).
M38421
For Installation of Sensing Bulb in Immersion Well
1. Loosen screw (at top of case, above scale setting),
and remove cover. Loosen 2 screws that secure
adapter clamp. See Fig. 1.
2. Insert the sensing element into the immersion well.
95-6120B—05 2
Fig. 2. Mounting bracket placement for vertical or
horizontal mounting.
ADAPTER
L1
(HOT)
L2
1
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
PROTECTORELAY
CONTROL
L4006A OR L4007A HIGH
LIMIT CONTROLLER
IGNITION
24 VOLT
THERMOSTAT
BURNER
MOTOR
OIL VALVE
(IF USED)
M1054C
1
2
3
4
T
T
1
2
3
4
T
T
IGNITION
BURNER
L4006B OR L4007B
CIRCULATOR
AQUASTAT
CONTROLLER
CIRCULATOR
L4006A OR L4007A LOW LIMIT
AQUASTAT CONTROLLER
L1
(HOT)
L2
L4006A OR L4007A
HIGH LIMIT
AQUASTAT
CONTROLLER
24 VOLT
THERMOSTAT
RA832A
SWITCHING RELAY
PROTECTORELAY
CONTROL
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
USE L4006E FOR MANUAL RESET.
1
2
M2855C
TT
XX
4
2
1
1
2
®
®
®
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
USE L4006E FOR MANUAL RESET.
1
2
M2856D
2
L1
(HOT)
L2
1
24 VOLT
THERMOSTAT
LOW WATER
CUTOFF
PRESSURE
CONTROL
L4006A OR
L4007A
LOW LIMIT
AQUASTAT
CONTROLLER
GAS
VALVE
PILOTSTAT
CONTROL
®
CLAMP
SPLIT SLEEVE
ADAPTER CLAMP
FITS OVER
GROOVE
L4006,L4007 AQUASTAT CONTROLLERS
SEALING WASHER
BULB COMPRESSION
FITTING
SENSING BULB
Fig. 3. Direct Immersion model with bulb compression
fitting partially removed.
Models Designed for Direct Immersion (without well)
For either horizontal or vertical placement of the
mounting bracket, see Fig. 2. Some models, which
provide for direct immersion of the sensing element into
the boiler, include a bulb compression fitting instead of
an immersion well. Install fitting in boiler tapping. Be
sure sealing washer is in place as shown in Fig. 3. Make
sure that spud of fitting is screwed in tightly enough to
prevent leaking. Insert sensing bulb through fitting.
Adjust the adapter clamp so that it fits over the groove at
the opening of the fitting. Tighten adapter clamp screws
so that Aquastat controller is firmly attached to fitting.
WIRING
Disconnect power supply before connecting wiring to
avoid electrical shock or equipment damage.
All wiring must comply with local electrical codes and
ordinances.
Refer to Fig. 4–9 for typical diagrams of Aquastat
controllers used in heating systems.
Fig. 4. Typical hookup for oil-fired gravity system, using
M8774C
Fig. 5. Hookup for oil-fired, summer-winter hydronic
system with domestic hot water using L4006A or B,
L4007 A or B. This Is typical where control for domestic
hot water is added, or where each Aquastat controller is
Fig. 6. Typical hookup for gas-fired system with
domestic hot water, using L4006A,E or L4007A.
3 95-6120B—05
L4006A or L4007A.
mounted in a separate location.
Loading...