What is the difference between Antifreeze and Boiler Antifreeze?

These two very different. Boiler anti-freeze is intended for use in boiler systems and has a different chemical composition than antifreeze intended for RVs, automobiles and trucks.

Aqua-Hot offers Century Boiler Antifreeze in both green and pink, in 1 gallon and 32 oz options.

If purchasing elsewhere, Camco has pink RV Plumbing and RV Freeze Ban antifreeze in addition to their pink boiler antifreeze; be sure to use the boiler antifreeze in your Aqua-Hot system

Where can I buy boiler antifreeze for my Aqua-Hot system?

Camco pink boiler antifreeze is no longer available directly from Aqua-Hot as well as most RV dealers. Century green and red come in both quart and gallon and is available directly from Aqua-Hot as well as most RV dealers.

*except for Aqua Hot 125D and 125G systems. *125D and 125G systems use a mixture of 50/50 Ethylene Glycol antifreeze and distilled water. Which is available at most big box or automotive retailers.

My propylene glycol antifreeze is discolored. Is this a problem?

Discoloration of propylene glycol antifreeze solution may occur during normal operation of the Aqua-Hot system.  This discoloration does not indicate a malfunction of the Aqua-Hot system or the antifreeze solution.

The following conditions may cause the antifreeze solution in your aqua-hot to change color:

Exposure of the antifreeze solution in the Aqua-Hot boiler tank to air
It is important to keep the overflow bottle filled to the proper level*.  If the Overflow bottle is empty, it must be refilled, and the tank must be bled of air*.  Air in the Aqua-hot boiler tank may cause the antifreeze solution to discolor.

Low Levels of propylene glycol in the antifreeze and water solution
The Aqua-Hot’s antifreeze solution should contain between 35% and 50% propylene glycol.  Operating the Aqua-Hot with less than 35% propylene glycol may cause the antifreeze solution to discolor.  Please see the Aqua-Hot’s Owner’s manual for instructions on testing the level propylene glycol in the Aqua-Hot’s antifreeze solution*.

Adding Tap or Well Water to the Aqua-Hot system
Adding tap or well water to your Aqua-Hot system may cause the antifreeze solution to discolor.  Aqua-Hot recommends using only deionized or distilled water.  Using tap or well water may cause corrosion of the Aqua-Hot system.

Mixing Century Brand (Green) and Camco Brand (Pink) Boiler Antifreeze
Motorhome manufacturers generally fill the Aqua-Hot with Century brand (green in color) or Camco brand (pink in color) boiler antifreeze.  Mixing these two colors together may cause discoloration of the antifreeze solution in your Aqua-Hot.

Discoloration of the Aqua-Hot’s antifreeze Solution does not indicate a malfunction of the Aqua-Hot system or the antifreeze solution.

Which Fuel Filter do I need for my Aqua-Hot hydronic heating system?

Aqua-Hot carries a few different types of fuel filters. Please compare these images with the fuel filter in your coach bay to determine which style you need.

Fuel Filter Brands Information:

Garber R Fuel FilterAqua-Hot Part Number: FLE-120-100

Racor Fuel Filter, R12T Spin-On, 10 MicronAqua-Hot Part Number: FLX-R12-TRA

Inline Fuel Filter, Webasto DBW-2010Aqua-Hot Part Number: WPX-603-359

What does the Low Temperature Cut-Off Thermostat light indicate?

200/250 Models: When the D4 (LTCO) light is off, the unit is up to temperature and ready to make interior heat. When the D4 (LTCO) light is on, either domestic water is being used, or the system is not yet fully up to temperature.

400/450 Models: A green LTCO light means that the heater is up to temperature and ready to make heat. When the LTCO light is not illuminated, either domestic water is being used, or the system is not yet fully up to temperature.

600/675 Models: The LTCO light will always be illuminated and does not impact hot water or heat functions.

How do I winterize the Aqua-Hot Hydronic Heating system?

Please follow these instructions when winterizing the Aqua-Hot’s Domestic Water Heating System:

1. Completely drain the fresh water storage tank.

2. Disconnect the domestic water demand pump’s suction line from the fresh water storage tank.

3. Attach an adequate piece of hose onto the suction side of the domestic water demand pump.

4. Place the opposite end of the hose into an adequate supply of FDA-approved “GRAS” RV Antifreeze and turn on the demand water pump.

5. Open and close all interior and exterior water faucets, one at a time, until only pure RV Antifreeze is present. Perform this procedure for both the hot and cold faucets.

6. Turn off Demand Water pump and remove the hose and reconnect the domestic water demand pump’s suction line to the fresh water storage tank.

An FDA approved “GRAS” rated winterization antifreeze must be used. YOU CANNOT BLOW DOMESTIC WATER COIL OUT WITH AIR TO WINTERIZE AQUA-HOT.