Air trapped in boiler

savage54

Well the percolation is back with a vengeance, can you suggest a product that will clean out the scale from inside of the residential boiler, it is 105,000 btu Weil Mclian boiler.

HVACNUT

Looking at the pic from your first post, there's no way for you to purge through the boiler. You need to pipe in a purge tee to the right side of the #3 ball valve. (I would remove the 90° and pipe in a heel tee.)
Close valve #3, open your newly installed purge valve, then fast fill, but watch the pressure.
Flow will go through the supply, loop around (monoflo ot series loop?) to the return, into the boiler and out the purge valve.
I'm surprised there's issue with air since Spirovent does a good job.
Are those pipes going into a slab?

savage54

I found out it is not air in the system, it’s scale in the boiler. I asking your input of how to descale a residential boiler, like what is a good brand of chemical flush? Thanks for the help

Alan (California Radiant) Forbes

Way to go, Steamhead!

hot_rod

http://www.rhomarwater.com/products/catalog/skale-x

One of many brands


Hercules Sizzle is another one I have used.

savage54

Thanks Hot Rod, I wil try the product u suggested. Hopefully it will solve the scale problem.

MilanD

For a steam boiler, I used Rydlyme. Great product. They have a line of them for different uses. Also a big plus, it's not hazardous.
http://www.apexengineeringproducts.com/

Just be aware: after you descale, any micropitts or rusts that now may be in place and holding the water may get dissolved and spring a leak.

nicholas bonham-carter

I wonder if reverse osmosis water would gradually dissolve out the calcium scale, and be less likely to remove the calcium plugs in any rust holes.—NBC

MilanD

nicholas bonham-carter said:

I wonder if reverse osmosis water would gradually dissolve out the calcium scale, and be less likely to remove the calcium plugs in any rust holes.—NBC

When I was looking at this, what I found was that nothing but chemicals can 'undo' a scale once the scale is there... Also, RO water has lower pH - which in itself is more corrosive (acidic, thus more corrosive, more hydrogen ions, and also why you should never consume RO water as drinking water). Bigger issue that needs investigating is why would a closed system, which technically should have no make-up, get make-up water introduced...

lchmb

If you have that much scaling I would begin to look for a leak also. It's possible some of your issue is from make up water...

savage54

Thanks for ur suggestion, but have visually inspected the entire system found no leaks. The make up water is well Water that has been softened.

lchmb

I'd say get some Fernox F3 ( think that's the one, check with a local supply house and explain your issue) ..run it through the boiler for a couple hours to break up all the sludge, then replace all the water in the system with an outside source. I'd also use a fernox treatment and monitor it yearly from there.. btw a visual inspection may not show a minor leak that evaporates.. pressure test the system..

savage54

Thank you guys for all the input, I will try one of the products and post which one and how it worked on my hot water boiler system.