Anti-freeze

Jlamb

Can anyone recommend the best method of actually getting anti freeze into the system ( proper transfer pump?) I have radiant in the garage, hydro coil in the attic and don't want to take the chance. We have a generator but tend to leave for weekends at a time.

RJMCTAFO

I use a regular pony pump. Make sure it's the proper product for your system. Can't stress checking your ph level at least yearly.

Bob Bona_4

Ugh. Antifreeze. Prepare yourself for a lifetime of upkeep on the concentration and inhibitor levels. High probability you will see corrosion from valve packings and seals, air vents will gum up, and it just is not good. Be aware the expansion tank and pumps can be undersized if they are on margin now.

If you HAVE to do it, you need to try to figure out your system capacity to get the ratio percentage right. Converted to gallons, isolate the boiler from the system and drain the boiler in 5 gallon buckets until you know you have room for the glycol. Then pony pump it into a purge valve, open the feed water to top off pressure and open system back up. Properly installed isolation valves, drains and backflow preventer are critical.

Think hard before committing to this-that was a basic overview. The fan coil and the air handler could be protected by freezestats, and the gen is a plus.

Jamie Hall

Ugh? Perhaps. I agree the stuff can be a nuisance to work with, and systems with it can be a nuisance to work on.

However... if one goes away for more than the length of time it would take the place to freeze, and the power goes off, you are asking an awful lot of the reliability of the generator and automatic transfer equipment. The amount of damage which a frozen hydronic system can cause is quite impressive (I've seen a house worth half a million declared a total loss that way).

And, after all, automotive (and now railroad) engines run hundreds of thousands of miles with antifreeze, and don't seem to mind with a bit of regular maintenance.

Bob Bona_4

You're a conscientous maintenance guy Jamie. Sadly, it's not the norm.

Cars and other equipment operate on a different environment. Besides ethylene vs polyprop differences...a few years back Hot Rod wrote a really good post on the subject. It is true you don't see the carnage like you do with hydronic systems, but I've forgotten the details

Gens need to be on the same maintenance schedule too!

hot_rod

If you go with glycol, plan on a yearly check of the fluid condition.

Inhibitors may need to be added. It is a more "leak prone" fluid, compared to water.

Remember also the circulator may need to be changed, or revved up

Ironman

Antifreeze - A necessary evil.
i agree with Bob that it can be high maintenance, but I also have to concur with Jamie that it's much better than the alternative of busted pipes.
We do a fair amount of solar and SIM systems which makes antifreeze mandatory - other than in drain back systems.
I have a manufactured pump cart which is made for this sole purpose, so that simplifies things for me. However, you can make one yourself with a pump, hoses and a plastic trash can from Lowes. Soggy shows how to do this in his book "Modern Hydronic Heating" which available from the book store on this site. Considering it will not only show you how to do it for 1/3rd of the cost, but also is a wealth of info, it's well worth the money.
Another thing that I would recommend is a method that Mark Eatherton showed us of using two expansion tanks to maintain system pressure and yet leave the fill valve closed in the event that a major leak occurred: the first tank you pre-pressurize the air side of the bladder to your incoming house water pressure. This becomes the fill tank. The second tank is your system's expansion tank and should be set for your normal system static pressure. You pipe the tanks together in series with your fill valve (PRV) between them, as well as isolation valves and a pressure gauge on either side of the PRV. The inlet feed line is piped to the Tee holding the fill tank and then the PRV and then the system is connected to the Tee that's on the lower pressure expansion tank.
Once the system is filled and pressurized with no leaks, you close the manual valve on the incoming house line and leave it that way. The first tank will maintain house pressure to the PRV which will maintain system pressure. If there's a leak, the most water that could be added would be the holding capacity of the fill tank - about 2gal at the most.

billtwocase

I use this only where needed. I would also recommend -100 Cryotec. I prefer my Wayne pumps, as Pony pumps barely get pressure up to 10 LBS. Sometimes you need higher to get the air out. You will also need to know about how much water the entire system holds, and the % that your boiler manufacture will allow.

Ironman

billtwocase said:

I use this only where needed. I would also recommend -100 Cryotec. I prefer my Wayne pumps, as Pony pumps barely get pressure up to 10 LBS. Sometimes you need higher to get the air out. You will also need to know about how much water the entire system holds, and the % that your boiler manufacture will allow.

Bill,
You can get that kind of pump at the big box store for under two saw bucks. It will produce 60 - 70 psi which about what my pump cart will do.