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Need help purging air from system

Pipes5780
Pipes5780 Member Posts: 4
I have trapped air in my boiler system and cannot understand how to remove it. I have no isolation valves, and the only purge valves I have are on the supply side just before the zone valves.

To describe the setup, boiler I have a hy-vent and a pressure relief valve. On the supply side I have an expansion tank and then out of the boiler it splits into 3 zones. Each zone has a purge valve and then the Taco zone valve. On the return, all 3 zones are joined together and also merged with a line from the home water line with a pressure reducing valve. Following that the return feed runs directly into the circulator pump. There is an additional purge valve under the circulator just before it enters the boiler.

Beyond that there are no isolation valves at all on the system and no additional purge valves.

Andy help would be appreciated!

Comments

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,317
    edited February 5
    Does the circulator have isolation Flanges? those are flanges with valves built in. Sometimes you need a screwdriver to close the valve. Sounds like you need to purge the air backwards, Can you take a picture of the boiler with the pipes from floor to ceiling and post it here?


    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • Pipes5780
    Pipes5780 Member Posts: 4

  • Pipes5780
    Pipes5780 Member Posts: 4
    Here is the circulator, no isolation flanges.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,317
    Looks like you are missing a valve

    Since the air was removed in the past, there must be another way to remove the air. What do your radiators look like?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • Pipes5780
    Pipes5780 Member Posts: 4
    All the same, simple baseboards with no control valves or air valves.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,317
    How are you at soldering? Can you add 3 ball valves at this location? Then you can use the fast fill feature on the autofeed to increase the pressure to the return side and then purge in reverse by opening one zone valve at a time.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,317
    edited February 5
    If you prefer no soldering, you can twist the pipes off with a pipe wrench. This Blue section of pipe can be removed by disconnecting the flange at the circulator and twisting the pipe that drops to the circulator pump. Then you can add a valve here with 2 short pieces of pipe. Then reassemble the pipes to the circulator pump and then you will have what you need to purge the system.


    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • hot_rod
    hot_rod Member Posts: 23,275
    Moving the expansion tank connection would help, and adding a backflow device. All that could be done to the left of the union on the fill valve piping

    An air purger would be nice also, but not so easy to add.

    I’d pull out the drain valves and press in 3 of these, no soldering required.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    EdTheHeaterMan
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,317
    hot_rod said:

    Moving the expansion tank connection would help, and adding a backflow device. All that could be done to the left of the union on the fill valve piping

    An air purger would be nice also, but not so easy to add.

    I’d pull out the drain valves and press in 3 of these, no soldering required.

    If you dont have a Propress® tool you can rent one form HD or Lowes

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    alTobine