Packless vs Orifice valve

Fizz

Have Richardson System, with 3 rads added in 30's, which have traps and old packless valves.  Thinking of changing valves on  them and one of Richardson's which was replaced with a packed valve.  Read where a packless is best, but then saw where orificing vaves which are spring packed can also be used.  Which is best for the system in place? 

gerry gill

If the radiators in question have traps,

then basically any radiator valve should work..however on two pipe steam i prefer to use the packless valve as the whole point of two pipe steam was to be able to modulate the valve, which implies it will actually get used..so i would rather see a packless valve used to eliminate the potential stem leakage issue..however if you desire an orificed valve then i kind of prefer the Mepco swrfb as it is readily apparent that it is an orificed valve. The orificed valves that have the internal screw are not so obvious that they are orificed and some times people think the valve is broke because the handle doesn't turn all the way, and they replace it with a standard valve and throw off the system..today most folks think the valve should turn all the way..we in the trade know different..The mepco swrfb allows the handle to turn all the way because it uses a separate orifice unit..if your other radiators are orificed, you may want to orifice the radiators with the real traps also, just to keep them from getting to much steam..balance is after all what your after.



http://www.mepcollc.com/steamspec/regv.htm

Henry

Valves

if you are replacing radiator valves, why not replace them with TRV such as the Danfoss units. They must be installed properly! We have done a number of commercial and residential buildings with them. They increase comfort and reduce the eneergy bill substantialy. One 6 story building owned by German interest we did one floor. The savings were so great within a few months, they had us do all the floors!