What do you circulate?

[ISeeDeadBTUs]

[quote author="Trzebs13" date="1289461950"]

Not to many of us use anything but straight water for the " Heat Transfer Fluid ".

Quick question for you guy's that run water. Do you add any kink of treatment? And if not do you change it? I went with the glycol because I wanted the protection and also was told that if I did that I would never have to change it out. Not really sure that is or is not the case? Thoughts anyone?[/quote]

I simply think Jim Beam needs to figure out the real issues with his newly acquired system, so I thought I'd comment here . . .

I run to a 20-plate HX. Year 1 I used a 50% mix. I had some small leaks. Also found that when the water °F dropped, I leaked more. At first I refilled with AF. Toward end of season I switched to water.

Year two I used some AF, but mostly water. Since then, I have been running straight water.

I drain the system when heating season ends, except when I have tried using it in the summer. I've since decided that burning in the summer without storage is not worth it.

One of the pros here (hr, TC, ?) suggested running the water backwards through the HX to flush it? Sounds like a good idea but I've never done it.

 

[Fsappo]

Rumors

 

[Deere10]

I run a 50/50 mix on boiler loop and house loop. House is forced hot air heat.

 

[Jesse-M]

I run soft water and add OWB conditioner I bought at the local supply house...flush at the end of the season...circulate occasionally during the summer...flush again before firing up.

 

[91220da]

50/50 water and Camco Boiler Antifreeze which has a built in rust/corrosion inhibitor. Third season still clean and red.

 

[in hot water]

All of the hydronic or solar antifreeze products will have inhibitor packages. Typically oxygen scavangers, ph balancers and some film providers. Better $$ brands have better inhibitors, look for the HD (heavy duty) label.

Really no need to flush and replace these fluids unless the ph drops in to the 7's. It will go into the system with a ph of 10- 11. if it starts dropping it indicated the fluid has overheated and/ or used up the inhibitors. You can boost the inhibitors but it gets expensive if the ph drops to low.

same applies to water, every time you flush and add new water you add minerals, O2, dissolved solids, etc and this all adds to potential scaling of the heat transfer surfaces. Leave the fluid in the system s the best advice.

I like to add a hydronic system conditioner. these provide the same purpose as the glycol inhibitors to protect the metals in the system, lock up hardness and balance the ph.

heck and maintain the fluids as you would with antifreezes. Softened water is better than hard water to add to a boiler or blend with glycols. DI or DM water (de-ionized or de-mineralized) is also better than tap water. But not RO or distilled water it can be too aggressive.

hr