Aqua-Hot 400 Series Service Manual page 20

Removing the Fluid Level Sensor probe:
1. Ensure that the Aqua-Hot has been completely shut
down and that all power sources have been disconnect-
ed. Also, because this procedure will involve the boiler
tank and the potential for hot coolant, be sure the heat-
er has adequately cooled.
2. Drain the antifreeze and water heating solution from
the Aqua-Hot's boiler tank using the drain valve.
3. Disconnect the fluid level sensor from the AMP circuit.
The circuit is connected via the boot terminal.
4. Using a 7/8" wrench, unscrew the fluid-level sensor
from the Aqua-Hot's boiler tank. It may be necessary to
use a 7/8" Crow's Foot wrench.
Figure 11
Level Sensor
Boot terminal
© Aqua-Hot® AHE-400-P01 Service Manual Rev.B June 2014
Aqua-Hot Components
Cleaning the level sensor:
1. Using a scrub sponge, clean the steel portion of the
probe of any build up of debris.
Reinstalling the Fluid Level Sensor probe:
1. Add a liquid thread sealant (such as Loctite ® ) to the
threads of the fluid level sensor.
2. Screw the fluid level sensor into the port on the Aqua-
Hot's boiler tank and tighten to 10 ft/lbs.
3. Connect the AMP circuit to the fluid level sensor via the
boot terminal.
4. Refill the Aqua-Hot's boiler tank with the antifreeze and
water heating solution.
5. Test for proper operation.
Ground Stud
AMP Circuit
Section #: Title
p.
20