Purging the Heating Loop
Filling the Aqua-Hot
©Aqua-Hot®
400D Installation Manual
Rev 220504
©Aqua-Hot®
400D Installation Manual
Rev 220504
p. 39
p. 38
8.
Fill the tank to approximately ¾ full, or until the “LOW
LEVEL SENSOR” item displays “TANK FULL”.
9.
Once the tank is partially full, deactivate the external fluid
fill pump and close the drain valve. DO NOT disconnect the
fluid pump.
10. Proceed to the next page to purge the zone before
attempting to start the unit.
Filling the Aqua-Hot
Before the first activation of the Aqua-Hot, fill the unit with
antifreeze and water heating solution. Without the solution
present, the Aqua-Hot will not operate, it will not deliver hot
water, and it will not deliver heat. Follow the directions below
to fill the Aqua-Hot with antifreeze and water heating solution.
In order to provide the best freeze protection, boil-over
protection, anti-corrosion, and rust protection, a mixture of 50/50
propylene glycol antifreeze and distilled water is recommended.
The Aqua-Hot 400D boiler tank holds approximately 5 gallons.
Be sure to use a “GRAS” (Generally Recognized As Safe)
boiler-type
propylene glycol
based antifreeze, rather than a
RV and Marine antifreeze or an automotive antifreeze/coolant.
The mixture may be modified to provide the most adequate
freezing, boiling, and rust/anti-corrosive protection. A 50/50
mixture of propylene glycol and distilled water has a freeze
point of approximately -34°C (-29°F) and a boiling point of
approximately 106°C (223°F). Reference page 52 for properly
measuring the antifreeze mixture with a refractometer.
Fill Instructions:
1. Locate the following items:
-Exterior fluid pump (a diagram pump if possible)
-The Aqua-Hot fluid expansion tank
-A bucket or pale
2.
Fill the bucket with the heating solution. Ensure the fluid
expansion tank is connected to its port on the Aqua-Hot.
3. Open the Aqua-Hot’s drain valve located at the front of the
heater. Reference Figure 76.
4.
Connect the external fluid fill pump to the fluid drain valve.
A ½” NPT barbed fitting is best for this task.
5. Place the supply line of the external pump in the receptacle
that contains the heating solution.
6. Locate the Reporter, and navigate to the “INPUTS FROM
AQUA-HOT” page.
7. Pay attention to the “LOW LEVEL SENSOR” item on this
page. See Figure 75.
NOTE:
Do not fill this unit completely. Filling the unit
completely runs the risk of air-locking, preventing the heating
zone from correctly circulating and draining the air.
Figure 76
Fluid Fill Port
Expansion Tank Port/
Air Release Valve
Freeze
Point (°C)
Concentra-
tion (%)
0
-4
-7
-9
-12 -15 -18 -23 -29 -34 -40 -46
0
12 19 25 30 34 38 44 49 53 57 60
Propylene Glycol
NOTE:
The Aqua-Hot’s boiler tank must be filled with the
antifreeze and water heating solution through the drain
valve, not through the top of the unit, to avoid air traps.
Only propylene glycol based “boiler” type antifreeze deemed
“GRAS” (Generally Recognized As Safe) by the FDA shall be
used in the Aqua-Hot’s hydronic heating system. Failure
to use the above specified antifreeze type could result in
serious injury or death.
Figure 75
Purging the Interior Heating Loop
In order to provide interior heat to the vehicle, antifreeze and
water heating solution is circulated within an interior “heating
loop” which distributes heat throughout the coach. During
installation, it is possible that air may become trapped within
the heating loop and hamper unit performance.
Follow this procedure to purge any air from the interior
heating loop.
Please note that if an RV-C or multiplex system is used in lieu
of the Aqua-Hot display, you must contact the manufacturer, or
connect a display to the on-board RV-C network to perform this
procedure.
Purge Procedure:
1.
Locate the fluid expansion tank of the Aqua-Hot. As any air
is purged, it will exit through to this expansion tank.
2. Locate a gallon of glycol antifreeze. This will be used to
top-off the fluid expansion bottle as air is purged from the
system.
3. Navigate to the “PUMPS” page of the “TESTING” section on
the Reporter as displayed below.
4. Tap each of the pumps (PUMP 1 & PUMP 2) to independently
activate them, beginning the heating loop purge procedure.
These pumps will remain active for a maximum of 5
minutes. They will need to be reactivated as needed until
the purge procedure is complete (at least 20 minutes).
5.
Continue to fill the unit as air is purged from the interior
heating loop.
6. Once the air is no longer returned from the heating zone
return ports, deactivate the fluid circulation pumps.
7.
Open the fluid drain valve, and activate the external fluid
fill pump. Fill the unit with GRAS propylene glycol antifreeze
and water heating solution until it reaches the “COLD”
mark on the fluid expansion tank.
8.
Once this has been completed, deactivate the fluid transfer
pump and close the fluid valve before disconnecting the
fluid transfer pump.
Figure 78
Figure 77
Zone 1
Circulation Pump
Zone 2
Circulation Pump
Purging the Domestic Water System
Purge Procedure:
1. Ensure that the vehicle’s domestic water pump has 12V DC
power, then activate it by opening each hot water faucet,
one at a time, and running the water until all air is purged
from the domestic water system.
2. Once the domestic water system is completely bled, check
for any leaks in the system.
Verify that the domestic water tank contains fresh water prior
to bleeding the fresh water system of air.
Cold Fluid Line
Figure 79
