boiler purging??

Reply

  #1  
Old 10-24-08, 06:00 AM
J
Member
Thread Starter
Join Date: Oct 2008
Posts: 3
Received 0 Votes on 0 Posts
Question boiler purging??

Hi, I have a 1960's American Standard boiler that has two zones, one of which is not heating. Can also hear water running so believe problem is that system needs to be purged? Read alot of info but none of set-ups seem to be same as mine so looking for advice before I attempt. There is pipe coming out of top that goes to a pressure relief valve then a hose bib, between the two there is a old galvanized expansion tank. The supply side exits the boiler and Tee's to the two zones. The return lines each have a hose bib and gate valve, after they come together there is another hose bib abd gate valve. Then the cold water supply Tee's into the line before entering the boiler. On the cold water supply there is a red B&G? reducing valve.
Thanks
 
  #2  
Old 10-24-08, 04:01 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Sounds like a straight forward job... but:

Before you start, what is the pressure reading on the boiler gauge ? and, have you observed what the pressure is when the boiler is cold, and again when it is hot ?

Reason to ask is want to make sure nothing else that needs attention first.
 
  #3  
Old 10-24-08, 05:46 PM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 2,180
Received 0 Votes on 0 Posts
Pictures of the piping would help in giving advice on purging.
 
  #4  
Old 10-27-08, 09:19 AM
J
Member
Thread Starter
Join Date: Oct 2008
Posts: 3
Received 0 Votes on 0 Posts
piping pictures

I couldn't upload pictures, so here is link to them. Pressure is between 12 and 15psi.

http://img.photobucket.com/albums/v2..._1724-edit.jpg

http://img.photobucket.com/albums/v2..._1725-edit.jpg
 
  #5  
Old 10-27-08, 05:21 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Jerry, you can put the images 'in-line' in the message by clicking that icon of the mountains above the compose window. You would need to past the 'direct link' on photobucket into the window that pops up...

I can't tell anything from the pics... too close, no way to relate them to the rest of the piping, so I'm going to go by your description and hope I've got it right. In the meantime, post more pics, from different angles, etc, so we can see how everything fits together.

One thing I want to add ... in the second pic, you see the pressure relief valve on top of the boiler... that must be piped down to within 6" of the floor ! Imagine the poor soul that just happens to be standing in front of that thing if/when it opens ! Talk about a SUNBURN! could even kill someone ... remember what happened to old Charlie Jones!

more---
 
  #6  
Old 10-27-08, 05:41 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Jerry, first thing is to look inside the heater cabinets (do you have fin tube baseboards ? radiators ? what ?) and see if there are any manual air bleeds there. If you can find them, they may have a coin slot, or a square 'clock key' head ... you can probably buy the key at HD or Lowe's if you don't have one. Get a cup and some towels (crappy ones, the water may be dirty), and open those bleeders and let any trapped air out.

The idea is to introduce as little fresh water as possible to the system because fresh water contains more air, and it will be a vicious circle... so start by trying to get that air out by using the bleeders if you have them. If not...

you may have to do a purge of the noisy zone... turn boiler off and let cool to 100F. Is the hose bib on the returns UPSTREAM of the gate valves ? If so, close BOTH of the valves on the returns by turning the handle perpindicular to the pipe. Connect a garden hose to the bad zone and direct it to a drain. Open the hose bib and let run until no more (or very little) air ... close hose bib.

Your red pressure regulating valve, does that have a FAST FILL lever on it ? If so, you can open that fast fill to get more flow once the drain is open.
 
  #7  
Old 10-30-08, 05:22 PM
J
Member
Thread Starter
Join Date: Oct 2008
Posts: 3
Received 0 Votes on 0 Posts
purging boiler more info

I have fin tube baseboard without manual air bleads. The red pressure valve does not have a fast fill lever.
Each of the return lines have a gate valve. The hose bib is between the junction of these return lines and the boiler. There is also a gate valve just after the hose bib, actually its part of the same fixture.

 
  #8  
Old 10-30-08, 06:53 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Sorry, I can't see a thing in those little bitty pictures...

After you turn the lever on the hose bib valve perpendicular to the pipe, put the hose there. Close all the gate valves except the one that is noisy. Open the drain and run until you don't see any air coming out. It helps if the end of the hose is in a bucket, cuz then you can see the bubbles.

The key here is to turn that lever on the drain valve. That way the feedwater is forced through the zone, and not just through that short piece of pipe, and out the drain ... you have to 'direct' the water to go where you need it ... water will take the path of least resistance.
 
  #9  
Old 10-30-08, 06:56 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Jerry, is there any piping that bypasses your pressure valve ? If there is, it will have a CLOSED valve on the line.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: