How to stop corrosion due to antifreeze?

Ital

Hi All, as I previously posted my Weil MClain block started to leak from one of the seams.
My house was built in 2003, but in 2005 in one occasion heat did stop due to frozen pipe, thank God it thawed out. Since that occasion I added antifreeze in the system to avoid the pipes that run in the attic to the air handler from freezing. However since then I started having nothing but issues. My gaskets from my water pumps started to deteriorate until I eventually started having a few failures.
The water pumps went, some of the pressure relief valves went, the pressure tank went. I finally had it so a few years ago I had the antifreeze all flushed out and I installed a programmable thermostat that basically every few hours calls for water so the pipes don't freeze. I also I've insulated the pipes going to the attic very well, thus I've been having no issue.

However I feel the corrosion has no stopped and not sure if this contributed to my boiler failing, what is the best way to stop the corrosion? I still have my old boiler hooked up, and this Tuesday my new Biasi will be going in. What is the best way to stop the corrosion\rust? Do I put something in the system before the new unit goes in? I've heard of a hydroponic inhibitor is that what should be used?

Thank you all in advance for the advise!

Jamie Hall

The correct antifreeze, with the correct corrosion inhibitors, will not cause gasket and seal failures nor corrosion. That said, it does have to be checked and maintained properly, as the corrosion inhibitors, particularly, are affected by any oxygen uptake by the water -- either through non-barrier plastic pipe, or by adding new water. There are also corrosion inhibitors made for hydronic (not hydroponic) heating systems which, while they do not have antifreeze properties will protect against corrosion as well as good antifreeze -- and which must be checked and maintained in exactly the same way.

Ital

I do not want to put anything in it. Is there anything I can put in it right now that will clean it up and stop any ongoing corrosion?
Or just having water in it would cause corrosion?

Thank you!

Jamie Hall

Just having water in it will accelerate corrosion, particularly if -- as I note -- there is any non-barrier plastic pipe involved, or if there are any leaks.

Corrosion inhibitors exist for a reason.

hot_rod

Once the glycol goes bad, ph drops, it gets dark and smelly, it is time to flush it out and dispose of the fluid.. You want to flush it out, then run a hydronic cleaner to get residual gunk out.

Start with fresh top brand glycol either pre-mixed or mixed on site with deionized or RO water in a clean system.

If you put fresh glycol in a dirty system you destroy some of the inhibitors pretty much right away.

As Jamie mentioned, yearly testing will indicate that the fluid is breaking down for some reason, ph is the main indicator, or send a sample to a lab for a more in-depth testing.

No reason it should not last 15- 20 years if is not over-heated (common run solar thermal systems), and installed and maintained properly.

Ital

Ok... I undestand now. I just placed an order for Rectorseal 68712 Quart 8-Way Boiler Water Treatment

Thansk!

pecmsg

First use the minimum amount of glycol. +20 freeze protection is generally more then enough

Check and control the PH level.

Ital

Any good videos on how to add an inhibitor to a hydro air system?
All videos I can find are related to baseboard or radiators.

Thanks!

Jamie Hall

Ital said:

Any good videos on how to add an inhibitor to a hydro air system?

All videos I can find are related to baseboard or radiators.



Thanks!

Don't know about videos -- but the principle is the same.

Ital

I'll ask my service guy to show me or have him do it every year.
I will have all the water flushed out and then have him add the inhibitor until the ph level is correct. Hopefully doing that once a year is all that I would need to do.

Thanks!

hot_rod

Unless you have a lot of O2 ingress, the fluid should not need a lot of maintenance.

These aerosol cans are the simple way to add cleaner and conditioners.

You will need a pump of some sort to push in the glycol and heat a good purge.