What is this pipe on my boiler, and why is it leaking?

  • Thread starter Thread starter DaveC426913
  • Start date Start date
  • Tags Tags
    Boiler Pipe
Click For Summary

Discussion Overview

The discussion revolves around a leaking pipe on a boiler, specifically focusing on identifying the pipe's function, potential causes of the leak, and implications for prospective home buyers. Participants explore the technical aspects of boiler systems, safety valves, and maintenance concerns.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Exploratory

Main Points Raised

  • One participant suggests the leaking pipe is likely a pressure safety valve on a mains pressure hot water system, which may require regular maintenance to prevent leaks.
  • Another participant expresses uncertainty about the implications of the leak, questioning whether it necessitates servicing and if a hose to a drain is needed.
  • Some participants propose that if the valve is leaking, it should be replaced, while others mention that a hose may not be necessary if there is no leak.
  • There are suggestions that the leak could be due to debris in the system, and that periodic "burps" of water might clear it out.
  • One participant raises a concern about whether the leak is a steady drip or intermittent, indicating different potential issues with the boiler.
  • A later reply shares a personal experience with a similar issue, suggesting that the problem may not be limited to the valve and could involve other components of the system.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the exact cause of the leak or the best course of action. Multiple competing views remain regarding the implications of the leak and the necessary repairs.

Contextual Notes

Some participants note the importance of a comprehensive diagnosis of the entire system, indicating that the valve may not be the sole issue. There are also references to specific maintenance practices and personal experiences that highlight the complexity of boiler systems.

Who May Find This Useful

This discussion may be useful for homeowners dealing with boiler issues, home inspectors, and prospective buyers concerned about the condition of heating systems.

DaveC426913
Gold Member
2025 Award
Messages
24,286
Reaction score
8,439
TL;DR
This pipe is leaking water. Is it supposed to?
A house inspector has noted this leak in our boiler. I don't know what this pipe is for. It seems to have some sort of steam release valve on top and it vents right out onto the basement floor.

Help! Prospective buyers want to know why our boiler is leaking.

boiler.jpg


1681575048131.png
 
Last edited:
Engineering news on Phys.org
It is probably a pressure safety valve on a mains pressure hot water system.
The instructions probably say to bleed it momentarily, once a month, to pretect the seat from corrosion, which will result in leaking.
 
  • Like
Likes   Reactions: russ_watters
That's kind of what I think. Though I know nothing about this stuff.

So, should the fact that it's leaking be a cause for concern?
Does it need to be serviced?
Also, I guess what it needs is a bit of hose that runs to a drain?
What I really need to do is assure the prospective buyers - basically today - that it's been (or being) remediated.
 
If it has started to leak, replace it.
No hose is needed, if it does not leak.
The water released, when the lever is operated, soon evaporates.
 
  • Like
  • Informative
Likes   Reactions: DaveE, russ_watters and DaveC426913
Probably it just has some crud in it. A couple of gallon-size "burps" of water may clear it out (bucket under exit pipe. But replacing it is sure bet. Not hard to do.
I like having the exit plumbing because it makes the mandatory triannual check of the valve mess-freeeee
It should not routinely let water out.
 
Last edited:
  • Like
Likes   Reactions: russ_watters
Thanks guys. We'll have someone replace the valve.
 
Do you notice a steady drip, or does the wet spot appear, dry up, and appear again?

The first is a symptom of a leaky valve, but the latter could be a symptom of the boiler exceeding design pressure. Mine used to blow off like that because there was no expansion tank installed on the cold fill line on the hot water tank.
 
Last edited:
erobz said:
Do you notice a steady drip, or does the wet spot appear, dry up, and appear again?
I didn't even know it was happening. It was the inspector who noted it, obliging me to investigate.
 
  • #10
DaveC426913 said:
Thanks guys. We'll have someone replace the valve.
erobz said:
Mine used to blow off like that because there was no expansion tank installed on the cold fill line on the hot water tank.
Or heating system stopped making heat. I noticed water had leaked out of the same pipe you have leaking. I found that if the system was filled until just before the leaking started that it made heat. I filled it (by lifiting the bail on the city water make up valve) when it was not running. Once the system came up to temperature, excess pressure slowly drove enough water out of system though the pipe that you have leaking and the heat would stop working. I didn't know what the actual cause was so I just kept overfilling it until the repair tech could get to us.

The actual problem was a jammed automatic bleeder valve which caused excess gas in the system.

The solution was to replace the bleeder valve the over-pressure valve and I think the expansion tank. The tech was not happy with my temporary

solution and zip-tied the bail on the valve down.

Make sure the whole system is diagnosed. It may not (only) be the valve that is at issue.

BoB
 
  • #11
rbelli1 said:
Make sure the whole system is diagnosed. It may not (only) be the valve that is at issue.
Yeah, that sounds like a home buyer problem, not a home seller problem. :wink:
 
  • Wow
Likes   Reactions: rbelli1
  • #12
DaveC426913 said:
Your honor I swear the house became a smoking crater after the signature was dry.
 
  • Like
Likes   Reactions: DaveC426913
  • #13
Like when the pictures in the sales brochure, become the evidence for the coroner.
 

Similar threads

  • · Replies 18 ·
Replies
18
Views
4K
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 31 ·
2
Replies
31
Views
5K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 42 ·
2
Replies
42
Views
6K
  • · Replies 2 ·
Replies
2
Views
4K
Replies
6
Views
3K