Aqua-Hot 431/12 User Manual

Antifreeze Leak Troubleshooting p. 1
SECTION 2: TROUBLE SHOOTING
Inspect the following components on the Aqua-Hot
Heating System for Leaks Model #’s: 431/12, AHE-
100-00S, 01S, 02S, AHE-100-03S & AHE-100-04S, AHE-
600 & AHE-675.
1.On the Front-Side of the Aqua-Hot:
A. Fluid Level Sensor/Float Switch
i. The 431/12 and AHE-100-00S, 01S,
02S do not have a fluid level sensor/
float switch.
B. Control Thermostat
i. The 431/12 and AHE-100-00S, 01S,
02S, do not have a control thermostat in
the antifreeze solution
C. Drain Valve Assembly
D. Electric Heating Element (s).
E. Circulation Pump (s).
i. When checking the circulation pumps be
sure to inspect the plumbing for the
hoses, the tank ports, and the circulation
pump.
F. Combustion Burn Chamber leak
i. When the Combustion Burn Chamber
leaks, the antifreeze will run out the tip
of the exhaust pipe.
2.On the Top of the Aqua-Hot:
A. Radiator Cap
i. bad seal
ii. Loose
B. Expansion Tank Tubing
i. cracked
ii. Loose
C. Filler Neck
i. Bent
ii. Broken nipple
iii. Bad solder joint
D. Supply and Return interior zone heat ports.
i. tubing/hose
ii. Brass fittings
Inspect the following components on the Aqua-Hot
Heating System for Leaks Model #’s:
HHE-200, HHE
-500, AHE-400, AHE-450.
1. On the Front-Side of the Aqua-Hot 400, 450/
Hydro-Hot:
A. Fluid Level Sensor/Float Switch
B. Control Thermostat
C. Drain Valve Assembly
D. Electric Heating Element
E. Circulation Pump (s) / Stir Pump.
i. When checking the circulation pumps be
sure to inspect all of the plumbing:
Hoses, the Tank Ports, and the
Circulation Pump.
F. Combustion Burn Chamber leak
i. When the Combustion Burn Chamber
leaks, the antifreeze will run out the tip
of the exhaust pipe.
Antifreeze Leak
NOTE: Newer model heaters do not have a radiator cap.
They will have a brass hose barb fitting, which the expan-
sion tank tubing connects to. There is also an air release
valve on the brass fitting, that may leak.
NOTE: To find an antifreeze leak, the system must
be Hot (up to operating temperature)
Or pressurized to 15 PSI.

Aqua-Hot 431/12 Specifications

General

Type	Hydronic Heating System
Fuel Type	Diesel
Voltage	12 VDC
Model	431/12
Heating Capacity	43, 000 BTU/hr
Dimensions	12.5
Number of Zones	2

Summary

Antifreeze Leak Troubleshooting Guide

Leak Detection Preparation

System must be hot or pressurized to 15 PSI to find antifreeze leaks.

Component Inspection: Models 431/12, AHE-100-00S, 01S, 02S, AHE-100-03S, AHE-100-04S, AHE-600, AHE-675

Details inspection points for specific older Aqua-Hot models.

Front-Side Components Check (Older Models)

Inspect fluid sensor, thermostat, drain valve, heating element, pump, and burn chamber.

Top Components Check (Older Models)

Inspect radiator cap, expansion tank tubing, filler neck, and zone heat ports.

Antifreeze Leak Troubleshooting: HHE-200, HHE-500, AHE-400, AHE-450 Models

Front-Side Component Inspection (AHE-400/450/Hydro-Hot)

Check sensors, thermostat, drain valve, heating element, pump, and burn chamber for specific models.

Top Component Inspection (AHE-450/Hydro-Hot)

Inspect radiator cap, expansion tank tubing, filler neck, and zone heat ports.

Back Component Inspection (AHE-450/Hydro-Hot)

Examine copper plumbing and interior zone return ports on the back of the unit.