© 2008 Aqua-Hot
®
450-DE/DM Hydronic Heating System Installation Manual
Section 10: Purging the System
Purging the Hydronic Heating System:
In order to provide the best freeze protection, boil-over
protection, and anti-corrosion and rust protection, a
50/50 mixture of “GRAS” approved boiler type pro-
pylene glycol antifreeze and water is recommended.
Reference Appendix D for additional information
regarding the antifreeze and water heating solution.
Be sure to use a “GRAS” boiler-type propylene glycol
based antifreeze rather than an RV and Marine anti-
freeze or an automotive antifreeze/coolant.
If assistance is needed in selecting an appropriate
50/50 antifreeze and water mixture, please contact
the Aqua-Hot Heating Systems Product Application
Department at 1-800-685-4298.
NOTE:
The Aqua-Hot’s boiler tank must be filled with the
antifreeze and water heating solution through the drain
valve and not through the top of the unit, in order to
avoid air traps. Reference Figure 48.
1.
Open the Aqua-Hot’s drain valve located at the front
of the heater. Reference Figure 48.
2.
Connect a piece of ½ inch PEX tubing (this piece
should be long enough to be used to transport the
antifreeze and water heating solution from its source to
the Aqua-Hot) to the drain valve.
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.
Ensure that the overflow tube is connected from the Aqua-Hot’s
expansion tank connection to the expansion tank’s bottom con-
nection and from the expansion tank’s top connection through
the overflow tube hole in the motorhome’s bay floor prior to
beginning this antifreeze and water heating solution fill proce-
dure. Failure to do so could result in an antifreeze spill in the
motorhome’s bay. Reference Figure 12.
Expansion tank connection
Figure 49
Figure 48
Drain valve
— Page 35 —
Summary of Contents for 450-DE Series
Page 1: ...Installation Manual 2008 Aqua Hot Heating Systems Inc...
Page 43: ...Appendix B Appendix B Wire Gauge Information...
Page 45: ...Appendix C Appendix C Electronic Controller Features...
Page 48: ...Appendix D Appendix D Antifreeze Types...
Page 50: ...Appendix E Appendix E Antifreeze Mixture Water Quality Recommendations...
Page 52: ...Appendix F Appendix F Antifreeze Terms and Mixture Ratio...
