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Hose on Pressure Relief Valve!

Ron Root_2
Ron Root_2 Member Posts: 12
Sorry about that, first time I've done this! So much to learn, and so little time! I hope this is better.


  • Ron Root_2
    Ron Root_2 Member Posts: 12

    While on a service call to repair a gas leak I noticed a hose from the pressure relif valve to a drain on a CGM 8 PI (unrelated to my call). I also noticed the monoflo tee's were on the return with the all the arrows opposing the flow. 1. is the pressure relief valve, 2. is the diaphragm-type expansion tank, 3. are the monoflo tee's, 4. is the supply. I've never seen a piping arragement like this, I guess it's worked that way for years. I'm guessing the relief valve leaks because one pump is getting 12 psi and when the water temperature rises from being heated it increases the boiler pressure over 30#. But I don't understand the monoflo tee arrangement. I would appreciate anyone elses thoughts on this.
  • Robert O'Connor_7
    Robert O'Connor_7 Member Posts: 688

    Unfortunatly, I need a car to drive from one end of your picture to the other, could you maybe shrink it a bit first? My eyes hurt... Robert O'Connor/NJ
  • Ed_13
    Ed_13 Member Posts: 164
    Size of your post

    Hey Ron,

    You have to delete that post, and reduce the document or picture before you post it again, It is not readable the way it is.

    Ed Carey
  • jim lockard
    jim lockard Member Posts: 1,059
    \"alright \"

    Last week I found a hose connected to the relief pipe, run across the basement to the sump pump hole. The boiler was cold and the pressure was 30 psi. More stuff for my to do list. best wishes J. Lockard
  • Attachment Size

    Ron and others,

    Here is the attachment in a more viewable format and size.

  • Ed_13
    Ed_13 Member Posts: 164
    Hose on relief


    Although that system described is not correct, the question would be is it causing the relief valve to deploy.

    How old is this system? How long has it been piped that way? Has the relief valve ALWAYS leaked while the unit runs? Does the relief leak when the unit is not running?

    If the system is relatively old and has always been piped that way, but the relief valve has started to leak recently, (relative to the age of the system), then something else has changed and is causing the relief to discharge.

    You may just have an odd system that just has a feed valve leaking through, or a defective expansion tank, or a bad relief valve. Don’t jump to the conclusion that the system design is the cause just because it is not right.

    Be sure to eliminate the common causes of a relief valve problem as though everything else is normal, before you try to re-engineer the rest of the system.

    After you are done, take the hose off and leave it off. If the relief valve does have to deploy a large volume quickly, the friction loss of that hose will cause real problems, (especially if it has a low spot causing a trap).

    Good Luck

    Ed Carey
  • Ron Root_2
    Ron Root_2 Member Posts: 12

    I wasn't there for any boiler related problems (gas leak at union inside from meter). I'm just curious about what I saw. Monoflo tee's all opposing the flow to the boiler, expansion tank location, pumps locations, etc. I guessed at the reason for the hose on the relief valve, and that the system has been working properly for a while. In other words, if this was your home what changes (if any) would you make, and why?
This discussion has been closed.