[Joe Galowitch]

OK I will flush it tomorrow. I did look at Google and found one place that said they are compatible but boiler anti freeze lowers the protection so I will call tomorrow and let you know. Maybe there are some engineers that know the answer? Anyhow Happy Thanksgiving and thanks for the help.

[Richard]

As an engineer, the motto is “In God we trust, everybody else bring data”. Meaning that no representative of a antifreeze company or Aquahot is going to tell you that it is OK to mix the products because they do not know what additive packages that may be in the mix. They do not have data on the unknown mix in your unit.

All the boiler fluid and antifreeze is ethylene glycol. Mix it and it’s still ethylene glycol. However, different companies use different additive packages to prevent corrosion and sedimentation. The reason that you are cautioned to avoid mixing is that two incompatible additive packages is that mixing them may cause them to precipitate and cause sediment in the system.

[Trainer]

Thank you Richard. Lot of work flushing a system including the heating loops. Lot of Fluid to dispose of.

[Joe Galowitch]

Thanks Richard that being said how would install coolant if all you knew was color? When I put my radiator in I wanted to go red but didn’t feel I could get all the old green out so I stayed with pre mixed green. So back to the aqua hot I am not sure what the capacity is so maybe less than one gallon might not be to bad.

[Richard]

As Rudy said, the safest strategy is to flush with distilled water. You could use tap water for a couple of flushes, and follow up with distilled water.

The coolant world is a nightmare. You cannot use color as an absolute indicator of what you have. The super safe route is to flush, and fill with the coolant of your choice. Document for yourself and future owners the coolant used.

[Trainer]

Joe, the Aqua Hot coolant tank has a 16 gallon capacity. The heating loops will be full of distilled water (2+ gallons) and do not need to be drained dry to properly flush the heating loops.

So you need 16 gallons of 50/50 engine antifreeze of your choice. Plus 16 gallons of distilled water to use in final flush after using 16 gallons of water from your hose for the first fliush.

You will catch 48 gallons of fluid during draining and flusihing.

The drain is through the floor near the back of the burner. I have used a large storage container with 5 or 6 inch sides so it will slip under the drain. As it fills, I have a Harbor Frieght 12 vdc pump that I use to pump it into 5 gallon buckets till the tank quits draining.

Your zone pumps do not prime themselves. So, you will drain the existing coolant, fill the coolant tank full with 16 gallons of hose water, use a raditor pressure tester to pump the tank up to 15 psi and run each of the zone pumps. Drain that and fill the coolant tank full with 16 gallons of distilled water. Use the pressure tester to prime your zone pumps again as you run them again. Drain that and fill the coolant tank full with 16 gallons of 50/50 engine coolant of your choice.

Lastly, use pressure tester to prime the pumps one last time and run them. You will know if the pump is primed as you can notice the return line flowing coolant from the pump(s) you are running.

Have fun!

[Joe Galowitch]

Wow thanks this sound like nothing but fun. I tried aqua hot this morning but no answer probably closed for thanksgiving. I guess I will go to harbor freight later and get busy tomorrow. Thanks guys I will let you know when I finish.

[Trainer]

Joe, There is 12 vdc at the fuses to run the HF pump. The pump has male water hose connections. My phone is on 8 to 8 central if you wish to consult.

[RegaNewell]

Rudy,

Are you saying to use 16 gallons of distilled water, and use 16 gallons of 50/50 Antifreeze? Why would you use the 50/50 verses the straight antifreeze? If that is the case that would not be a true 50-50 mix? I am confused.

They way I understand it is 16 gallons of distilled water, then use straight antifreeze which would be 16 gallons total of antifreeze. Please explain so this Okie blonde understands.

Thanks
Pam

[Richard]

Pam,

The procedure for flushing is flush once with 16 gallons of tap water, flush a second time with 16 gallon of distilled water, then fill with 16 gallon of 50/50 antifreeze. You do not dilute the 50/50.