Help Bleeding Boiler

Are you "bleeding" or "purging"? What is your process?

I will look forward to what the people with a lot more experience have to say, but I think that your method above doesn't provide enough water fast enough to push the air out.

The water goes in slowly with your process (I believe), and the air bubbles stay upstairs in the pipes/convectors.

You might have to hook domestic water hose to the system and blast water through one zone at a time in order to flush it (what I referred to as "purging" above, I'm not sure the real term).

If you have radiators, I believe they must be bled at the radiator…you can't flush the air out of those from the basement.

 Also, shouldn't most the air auto bleed form the air bleeder?

If you have too much air in the system, the water will not flow, and the auto air remover thing can't do its job.

I look forward to seeing how mistaken I am in the thoughts above, so don't rely on them yet!

Yep, that's why I said "if you have radiators". Sounds like Hot Rod set you up with the good info!

I get it. I like them without bleeders because then there's no chance for air to find a way in.

I was just helping a woman who had 3 different plumbers/HVAC techs come in to troubleshoot her leaking PRV. She told each of them she wanted them to empty her expansion tank because she suspected it was waterlogged. Each one tapped on it and said it wasn't the problem.

I hooked a hose to it and drained 16 gallons out of it and then her system worked like a dream. She was right the whole time but they wouldn't listen to her, or look at the evidence.

It was an old bladderless one up in the joists like they used to do. One of the guys told her the bladder wouldn't let it get waterlogged, which is wrong in several ways.

Purge it cold. When you first run it again, more air will come out as the water temperature increases.

Looks like this vent is fairly new? You should hear air come out when you start warming up. Run all the zones to be sure everything is air free.

Does the boiler operate on an outdoor reset control, varying the temperature? Are there multiple low temperature zones?

Seems like people who collect money to come work on a hot water boiler should know what a compression tank is.

Coin key vents never leak, good to know!

Not more than sweated baseboards? I still say it's good to limit the places where leaks can occur. Anyway, details details

any valve or devices that seals water has the potential to leak.

A spec of dirt is all it takes , in a needle valve type bleeder, plus the threaded connection.

One high point vent could be helpful, but you should not need bleeders on every fin tube

Once you have flow the rest of the air should make it back to an air purger

you need ot use the boiler drain in the retiur rather than the supplyand close one of the isolation valves at the boiler.

There's a boiler drain on the return now circled in green. The drain circled in red is on the same pipe as the prv.

the return pipe from radiant, turn the yellow handle off, connect hose to bib to its left. That purges the radiant

you can't get all of the air out by purging, you just are trying to get enough out to get it to circulate then the air elimination removes the rest. the fresh water you added has dissolved air in it that will come out when it is heated so it is impossible to remove all of the air by purging unless you had a pump ad a tank of deaerated water.

this type is a lot more effective

https://www.supplyhouse.com/Caleffi-551028A-1-1-4-Sweat-DISCAL-Air-Separator

increasing the temp and pressure temporarily can help. an automatic vent on the boiler itself may also help.

The purge like you have struggles to get entrained air out of the fluid.

Cranking the temperature to 180 for a few hours can help drive the last air out, as well as increasing fill pressure to 20 psi or more for that period.

Microbubble type air seps work much better. They have a mesh or media inside to catch the tiny bubbles.

Moving the handle position on that blue 4 way can help divert more flow to either loop and sometimes help purging.

I have seen that issue before with the Watts. Not sure what fails to prevent the pin from being depressed. You might need to replace it to get the fast fill to work.

The Caleffi PRV with the gauge is superior.