What is the proper way to use antifreeze in a HW oil heating system?

Bill Julian

I am installing a WM gold oil in a garage that is going to be unheated I need to use antifreeze never done it before not sure how to get the anti freeze into the heating system. Bill

icesailor

If the boiler is going to be running, and you don't leave the doors open 24/7 when it is cold outside. why do you need antifreeze? No garage I ever had (all were unheated) any stored water freeze.

Anti-Freeze in heating systems is like giving yourself the Chicken Pox. You might get Shingles, you might not. The Shingles Vaccine might give you the Chicken Pox. They might give you Shingles. They might not do anything.

IMO, you need a better reason to Anti-Freeze a system than that the garage is unheated. The boiler alone will make the garage Semi-Heated.

Tinman

If it's a detached, uninsulated garage and you live anywhere near where I live (northwest suburbs of Chicago), antifreeze is a very good idea. I use a Wayne 1/2hp porta-pump to pump it in from very clean buckets or 50 gallon trash can. Boiler drains on each side of a ball valve makes it really easy.

Tinman

You'll need 3 short heavy duty hoses like they use with washing machines or something similar. The ball valve will be closed while pumping in the glycol, the hose connected to the inlet of the pump will drop into your bucket of glycol mix, the hose connected to the outlet of the pump will connect to one of the boiler drains ( the one on the leading edge of flow), the last hose will go from the remaining boiler drain back into the bucket of solution. Make sure your pump is primed and be aware of the system pressure so as not to exceed the rating on the relief valve. The boiler drains, of course, will be open while pumping/purging.

Tinman

I've tried a few different pumps. This is my favorite.

SWEI

Finally sprung for one of these earlier this year. Definitely sped up the process for us.

j a_2

I agree glycol is a very good idea, be sure to follow boiler and glycol directions……Best get yourself a good refractometer..I know you know to use propylene and not ethyline glycol;….Propylene glycol, is what we used to deice airplanes with…mixture depended on out door temp.

icesailor

@Stephen Minnich:

Good pump. Here's another way to do it. Saves a lot of aggravation. You need at least 3 five gallon buckets. Blow the entire heating system out with air. measure the amounts by filling the 5 gallon buckets so you know how much liquid is in the system. No guess work. You will get every drop of water out of the system with air. Even if there are low points that don't drain, you will get an accurate amount of liquids to measure. If you use 5 gallon anti-freeze buckets, you know what the full level is. Measure the contents of the water in the system. Determine your solution percentage based on what you removed. Have a hose for fresh water. Connect the Handy Pump to the system to pump in, and another washing machine to suck the solution from a antifreeze bucket. If you need 4 buckets of anti-freeze, pump that in first, and add the remaining water as pure water, so many five gallons of water at a time. When time to vent & purge, suck fresh water out of the bucket. Purge the system back into the suck bucket. You purge through the pump, add water pressure as you need it.

If you need to increase the strength of the solution, draw an equal number/amount of mixed solution and pump straight 100 Proof antifreeze. When done, flush out with pure water to clean the pump out. Save the solution removed, and make the bucket with the strength of the solution and the date.

You may have a better way. That always worked for me.

icesailor

j a said:

I agree glycol is a very good idea, be sure to follow boiler and glycol directions……Best get yourself a good refractometer..I know you know to use propylene and not ethyline glycol;….Propylene glycol, is what we used to deice airplanes with…mixture depended on out door temp.

There are a number available out there. This one is relatively bomb proof. Don't leave it in the box on the dash of your truck. The heat can wrinkle the decal with the scales on it.

You can sent it back and have it recalibrated for short money. They are really easy to work with.

https://www.misco.com/traditional-refractometer/traditional-refractometer/glycol-battery-tester-refractometer-freeze-point-specific-gravity-7084vp

The ability to check the battery is nice too. It checks both types of Anti-Freeze.

Bridgerman

Bill Julian said:

I am installing a WM gold oil in a garage that is going to be unheated I need to use antifreeze never done it before not sure how to get the anti freeze into the heating system. Bill

Hi Bill,

There is a product that you can use that cycles the water from the boiler periodically into the zone you are concerned about. This way, you don't need to use anti-freeze. The product is called ThermGuard. You can search the internet for more information. You can add it on your thermostat, any thermostat, and you can program it to come on every 3 hours for 2 minutes, for instance. It is completely user programmable to whatever you want to run.

It also remembers your settings when powered off, so once you set it, you never have to again. ThermGuard doesn't require any batteries either, so there is never any maintenance.

I had my pipes freeze (in Montana) twice and I have never had a problem once the ThermGuard was installed.

Good luck,
John

hot_rod

clean the system first, use a hydronic cleaner or TSP. Buy the glycol pre-mixed so it has good quality blend water.

Don't use the real inexpensive brands, the $$ relates to the inhibitors that are added.

freeze protection and Ph should be checked every few years.

Remember the pump de-rate also.

pecmsg

Unless it's absoutly needed I would avoid anything in the boiler. Glycol adds another layer of maintenance to your equipment.
Life span 5 years + or - .
PH level needs checking.
10 - 20%

pecmsg

10 - 20% drop in capacity.

hot_rod

the lesser of two evils

Yes glycol does bring along some baggage, it is tougher to circulate, and does not transfer heat as well as water. But sometimes it is the only way to protect systems.

Plenty of HW and chilled water systems and GEO systems run glycols.

Glycol can last 20 years or more if it is checked and maintained.

It needs to go into a clean, tight system, needs to be blended correctly with DI water.

Only if the inhibitors breakdown, or get "used up" does glycol go bad.

Check Ph yearly, it should run 10.5- 11.5 when installed. If it drops Ph every year it is being over-heated or you have O2 ingress depleting the inhibitors. Or it was blended with hard, mineral rich water.

Dow has a free engineering guide that is an excellent source of info, both for PG and EG.