Zoning with thermostatic valve electric actuators

Chuck_17

Any down side to the following?

A church with a two pipe system and main serving classrooms on the lower level and sanctuary above. They want to use the classrooms during the week without heating then entire sanctuary. If we install thermostatic valves with electric actuators on the sanctuary radiators we can shut them off (or control at much lower temperature) while heating the lower level. This would effectively reduce by say 75% the load the boiler sees.

Jamie Hall

There is an obvious down side...

which you are probably aware of.  The boiler will short cycle on pressure, since it will effectively be way oversize.  It will still use less fuel than running the whole show, but not as much less as you might think.



Depending on how the piping is arranged, you might want to use a valve on a steam main, rather than on individual radiators.  If you were to do that, that valve must -- absolutely must -- be full port.  Which could be pricey; you'll want to look into the most cost effective way to do that.  Also if you were to do that, you will need a drip to a cold return on both the hot and cold side of that valve.



Do not valve off the returns, either wet or dry.

Chuck_17

Main valves

In this case the mains can't be zoned because they serve both the radiators for which we want heat (down), and the radiators we don't want heat (up).