L7224U OIL ELECTRONIC AQUASTAT
®
CONTROLLER
3
69-1720—03
Fig. 2. Removing horizontal or vertical mounting
knockout.
8.
Loosen but do not remove the well clamp screw.
9.
Fit the case into the well so the clamp on the case
slides over the flange on the well.
10.
Securely tighten the clamp screw.
11.
Insert the sensor element into the well until it
bottoms. (If necessary, slightly bend the wire inside
the case to hold the sensor against the bottom of
the well.)
12.
Turn power ON.
13.
Set High Limit, Low Limit and Differentials to the
settings recommended by the boiler OEM. (See
OPERATION section, also refer to INSTALLATION
steps 6 and 7.)
IMPORTANT
Best thermal response is obtained with a well
that snugly fits the sensor. Insert the sensor until
it rests against the bottom of the well. Use a well
of correct length and bend the wiring, if neces-
sary, to hold the bulb against the bottom of the
well.
If the well is not a snug fit on the sensor, use the
heat-conductive compound (furnished with
TRADELINE
®
models) as follows: Fold the
plastic bag of compound lengthwise and twist it
gently. Then snip off end of bag and work the
open end of the bag all the way into the well.
Slowly pull out the bag while squeezing it firmly
to distribute compound evenly in the well. Bend
the wiring, if necessary, to hold the sensor
against the bottom of the well and to hold outer
end of the sensor in firm contact with the side of
the well. See Fig. 3. Wipe excess compound
from the outer end of the well.
Fig. 3. Position of sensor in immersion well.
Flush-Mounted Aquastat Replacement
Turn off all power and remove the old controller. Refer to
the cover insert of the old controller to identify and tag
each external lead as it is disconnected. If the old well is
unsuitable for the new installation, remove it and replace it
with a suitable new well. If the old well is suitable, use it.
See Fig. 1 and 4 for mounting tab location.
Fig. 4. Location of L7224U flush-mounting tabs and
LEDs.
SCREWDRIVER
M22118
KNOCKOUT FOR
HORIZONTAL
MOUNT
KNOCKOUT FOR
VERTICAL MOUNT
SENSOR WIRES
IMMERSION WELL
CLAMP SCREW
IMMERSION
WELL CLAMP
M16120
HEAT-CONDUCTIVE COMPOUND
(OPTIONAL)
CONTROLLER CASE
BOILER
IMMERSION
WELL
SENSOR
C1
B1
ZC
L2
LINE
C2
ZR
TX
L1
B2
T
T 3
2
1
THERMOSTAT
TERMINALS
ENVIRACOM
TM
TERMINALS
DISPLAY
SENSOR
CONNECTOR
SENSOR HOLES
FUSE
RELAYS
RELAY
FLUSH MOUNTING TAB (2)
M22119A
TRANSFORMER
CAPACITOR
LED's
TT
B1 ZC C1
