Service manual

— Page 30 —
© January 2013 Aqua-Hot
®
600-D01 Series Hydronic Heating System Service Manual - Rev. A
SECTION 4: AQUA-HOT COMPONENTS
Tempering Valve:
The tempering valve for the Aqua-Hot mixes the heated do-
mestic water from the boiler tank with cold domestic water at
a preset ratio to reduce the risk of scalding.
Troubleshoot the tempering valve if the following condition
has occurred:

There is a lack of hot domestic water.
Troubleshooting:
1. Inspect the tempering valve to ensure that it is not
leaking.
2.
Test the temperature of the hot water using a digital
thermometer at one of the hot water faucets. Water
Temperature should range between 115° F - 123° F. If
the proper range cannot be set follow the instructions in
this section to replace the tempering valve.
3.
Test the tempering valve’s functionality by turning the
knob.
If the tempering valve’s knob does not turn freely, fol-
low the instructions in this section to replace the temper-
ing valve.
Replacement Procedure:
FAILURE TO DISCONNECT ALL POWER SUPPLIES AND/OR
TO ALLOW THE HEATER TO COOL BEFORE SERVICING
COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY.
1.
Turn the motor home’s water pump off.
2.
Drain the water pressure by opening the faucets and
allowing the water to drain.
3.
Remove the Diesel Burner from the Aqua Hot.
4.
Disconnect the motor home’s water lines from the
tempering valve assembly.
5.
Disconnect both the Hot and Cold Pex pipe fittings from
the boiler tank.
7.
Remove the tempering valve assembly from the Aqua-
Hot by lifting it up and out.
8.
Remove all fittings from the defective tempering valve,
and clean to be reused.
9.
Wrap the threads of the brass fittings with a thread seal
tape, on the side that screws into the tempering valve,
and Install the brass fittings onto the replacement tem-
pering valve.
10.
Install the replacement tempering valve onto the Aqua-
Hot.
11.
Reconnect the Pex pipe fittings on the tempering valve
assembly to the Aqua-Hot. Be sure to inspect the rubber
seals and replace if necessary. DO NOT OVERTIGHT-
EN.
12.
Reconnect the motor home’s water lines to the temper-
ing valve assembly.
13.
Turn the motor home’s water pump back on and check
for leaks and the presence of hot domestic water.
14
. Verify that the replacement tempering valve has been set
to the proper setting by taking a digital thermometer to
a hot water faucet and set the water temperature between
115*F - 123*F.
15
. Secure both the Domestic Water Access Panel, and the
Thermostat Access Panel in place.
NOTE: Prior to trouble shooting the tempering valve, it is
recommended to review the Lack of Hot Water Trouble
Shooting guide in section 10.
NOTE: You can also test the tempering valve by running
hot water in the motor home and locating the HOT water
inlet pipe that goes in to the mixer valve. If the HOT water
inlet pipe is hot, but you are only getting luke warm water at
the hot water faucet, and the valve does not adjust, then the
mixer valve is defective and will need to be replaced.