We have a safety relief valve on ou
We have a safety relief valve on ou
(OP)
We have a safety relief valve on our 175psi steam header. The discharge of the relief valve is piped through the building and up through the roof. A drain leg w/ temp probe and control valve is piped to the floor.
I assume whoever installed this setup thought that as condensate cooled below the 175psi steam temperature, the control valve would open and allow it to drain to the floor. And if the relief valve would lift, the higher temperature would trigger the valve to go closed.
It seems to me that this setup can all be simplified with a steam trap. Any thoughts?
I assume whoever installed this setup thought that as condensate cooled below the 175psi steam temperature, the control valve would open and allow it to drain to the floor. And if the relief valve would lift, the higher temperature would trigger the valve to go closed.
It seems to me that this setup can all be simplified with a steam trap. Any thoughts?





RE: We have a safety relief valve on ou
It sounds like the control valve can be replaced bya thermostatic steam trap.
Is the collection of condensate on the outlet side of the relief valve ? If so, the condensate would be at atmospheric pressure and I would see no need even for a trap. (a periododic drainage of the collected condensate should suffice)
If the condensate collects on the inlet (HP)side of the trap, ensure that any new steam trap is sized for steam system start-up. Condensate loads under start-up can be many times the normal flow
My thoughts only...................................
MJC
RE: We have a safety relief valve on ou
I've never seen a temperature control valve on this type of application but I think a steam trap is perfect for it. It would drain any condensate on the drain leg and high pressure steam would still be forced up through the vent.
RE: We have a safety relief valve on ou
It may also be, that this control circuit was set up to guarantee that the discharge side of the RV is free draining, normally must traps require some motive energy to operate correctly and when the RV closes you lose that energy.
Just my two cents worth.
saxon
RE: We have a safety relief valve on ou
RE: We have a safety relief valve on ou
saxon seems to indicate that 'most' steam traps don't work without some motive force while ihg says the steam trap on the drain leg would work even while the PSV is seated.
ProjectEng
RE: We have a safety relief valve on ou
When the PSV relieved, the hot steam would cause the trap to close. I'd look at something like an inverted bucket, a thermostatic trap would allow some steam to blow through the open trap I'm thinking before it would respond to the rising temperature and close off, I'm just not sure how fast those things respond.
RE: We have a safety relief valve on ou
I agree with TDK, there are quite a few float types that can easily shut-off against the back pressure in the vent pie (during full lift conditions).
Usually the drain is just poiped to a drain. If you have a high capacity relef valve, you need to check the built up back-pressure. It can be significant.
RE: We have a safety relief valve on ou
TD2K is correct in stating that an inverted bucket trap is another reasonable choice for this service.
A quick discussion with a technical rep from Armstrong Int'l or Spirax Sarco would confirm the trap choice.
Saxon states "....normally must traps require some motive energy to operate correctly...." Yes, that is true, and the difference in system pressures make these devices reliable, simple, cheap and in use all over the world......why would you want to try anything else ?
My opinion only........
MJC
RE: We have a safety relief valve on ou
This whole setup scares me.
RE: We have a safety relief valve on ou