BAC Forum

General Boards => Technical Support => Topic started by: Fred Cook on January 14, 2020, 12:18:20 AM

Title: Which antifreeze?
Post by: Fred Cook on January 14, 2020, 12:18:20 AM
 I have a 2002 aqua hot system in my coach. It is low on antifreeze so which one should I use? I know that it is green but is it full strength or is it 50/50?
Title: Re: Which antifreeze?
Post by: Steve Huber Co-Admin on January 14, 2020, 12:24:22 AM
Fred,
It is supposed to be 50/50.
Steve
Title: Re: Which antifreeze?
Post by: Fred Cook on January 14, 2020, 01:23:48 AM
 Thanks Steve. I had bought some 50/50 earlier but thought I would ask just in case before putting it in. Fred
Title: Re: Which antifreeze?
Post by: John Compton on January 14, 2020, 01:46:22 AM
You need to use antifreeze designed specifically for boilers. Not the green automotive type.

EDIT: It seems my statement may be incorrect. Apparently some models of the Aqua Hot use a different
         type of antifreeze than my model.
Title: Re: Which antifreeze?
Post by: William Jordan on January 14, 2020, 03:06:21 AM
A 2002 a ... ah100-2? uses normal green auto antifreeze. the water lines are outside the tank unlike newer models with the water coils inside the boiler.They use the non toxic boiler fluid to prevent contamination on newer designed units
Title: Re: Which antifreeze?
Post by: Bill Sprague on January 14, 2020, 04:46:23 AM
You need to use antifreeze as specified by AquaHot.  On our '04 it was ethylene glycol for the HydroHot.  It was not propylene glycol based boiler antifreeze.   

At about 10 years I had to be taught a lesson.  Over the years of ownership I would had a little 50/50 mix to keep it full.  When measured during a "severe" service the mix was very heavy with ethylene glycol.  Why?  It does not evaporate like water.  So, gradually as the water evaporated and I added the mix, the concentration became too strong. 

If you have an older rig and want to do it right, get a antifreeze refractometer. 
Title: Re: Which antifreeze?
Post by: Bill Lampkin on January 14, 2020, 03:25:54 PM
Here is the word from AH on boiler fluid

http://www.aquahot.com/faqs.aspx
Title: Re: Which antifreeze?
Post by: Bill Sprague on January 14, 2020, 05:43:19 PM
Just be sure you know what year your Hydro/AquaHot was manufactured.  Monaco seems to have used an "old" one in our '04 that was built in '03.   
Title: Re: Which antifreeze?
Post by: David T. Richelderfer on January 14, 2020, 08:03:13 PM
I would submit it is mandatory for us owners to know the model number of the Aquahot/Hydrohot unit (ours is the AHE-100-02S) and have ready access to a service manual.  For example, our Aquahot's service manual link is:

http://www.aquahot.com/files/service_manual/AHE-100-02S%20Service%20Manual%20Rev.%20B%209-27-2011.pdf

And on page 8 it says "antifreeze type used...  Ethylene Glycol".  The service manual is over 100 pages with good explanations of maintenance and troubleshooting.  The manual is full of color pictures to describe in detail the many aspects of the unit.
Title: Re: Which antifreeze?
Post by: Bill Lampkin on January 14, 2020, 11:42:03 PM
What I get from reading the info from Aqua hot is this:

Pink and green are colors, they do not denote one chemical or the other (ethylene glycol or propylene glycol)

You can use propylene glycol in any AH unit, but you can't use ethylene glycol in the 2004 up AH units

Don't mix pink and green boiler antifreeze


There is much confusion about this, so if what I have surmised is incorrect, I welcome your corrections

And as David said, there is no substitute for reading the AH manual that came with your Beaver
Title: Re: Which antifreeze?
Post by: Bill Lampkin on January 14, 2020, 11:48:36 PM
Correction; AH from 2002 and up use propylene glycol, not 2004 as I misstated.
Title: Re: Which antifreeze?
Post by: Richard Muha on January 18, 2020, 04:33:51 AM
I use this in my 2008 Marquis.  My Aqua Hot is a 600D. 
Title: Re: Which antifreeze?
Post by: Fred Cook on January 18, 2020, 01:20:36 PM
My coach was built late 2001 and labeled as 2002 thus... it uses ethylene glycol. It does a great job. Thanks everyone!
Title: Re: Which antifreeze?
Post by: LaMonte Monnell on January 18, 2020, 02:52:45 PM
i bought a refractometer on Amazon and now I test the mixture once in a while to keep it at 50/50. If you get too much of the ethylene glycol it gets too sticky and clogs the valve up.
Title: Re: Which antifreeze?
Post by: Joel Ashley on January 18, 2020, 08:41:57 PM
There are lots of refractometers at Amazon, and based on several factors I zeroed in on this one a few months ago.  You can measure more than just antifreeze, e.g. battery fluid:   

Ade Advanced Optics aaogabf100atc Fahrenheit ATC Glycol Antifreeze/battery Fluid Refractometer.

Copy and paste the above into Amazon’s search field.

Joel