Boiler piping with Glycol - blue green joints

Upnorth45TC

Wanted to see what your opinions are on boiler piping connections in regards to systems holding glycol? I recently relocated to northern MI and am seeing boiler systems that commonly have symptoms of small leaks indicated by bluish green joints. Commonly seen around valves and other components. The area I am servicing is still commonly copper piping and solder joints on boiler systems. Are these leaks indicative of poor solder techniques or just the way things are with glycol or antifreeze systems? Have there been noticeably differences with Propress fittings in your experience?

kcopp

This happens in many systems w/ glycol in them. Systems that have been fine for years w/ water have glycol added and then a year or so later… boom.

I have seen it w/ propress also.

I am NOT a fan of glycol unless it is absolutely needed. Proper building practices and insulation are better anyways.

If you must… clean the system well before and use no more than a 50/50 mix preferably a premixed version.. Check the system yearly to see if it is still in good shape pH wise and effectiveness.

pecmsg

glycol works BUT you have to be careful with the concentration. 10-20* freeze point. Check the PH annually and adjust.

hot_rod

welcome to the world of glycols!

Yes a weak solder joint will be the first to show the seeps. Same with crimp and press joints.

It has to do with the lower surface tension of the glycol blend.

So keep the mix percentage low, 30-35 should be adequate? check the ph every few years.

Unfortunately there is no easy fix other than to redo the leaky joints.

Does the system need to have glycol? If all the piping is indoors, plain water is less leak prone.

mattmia2

glycol flows more easily and evaporates very slowly so it shows you where the leaks are. other systems have those leaks too, you just don't have an indication of the leak.