TRV's on a closed loop system??

Matt_29

Please correct me if I'm wrong, the system used is a residential, gas fired, hot water boiler, simple closed loop one pipe system (in one radiator and out to another)
I dont believe that TRV's can be used??? wouldn't slowing down the flow of water through one radiator cause a whole system problem...or is there a method of plumbing a closed loop system that would allow the use of TRV's, explain and be technical please!! thanks !!

Mike T., Swampeast MO

It can be done with various different bypass schemes. Requires careful calculation and a quite well-balanced system to begin with.

Years ago someone here posted a link to a VERY good document by Danfoss: "Design of Radiator/Convector Configurations in a One-pipe and a Two-pipe Installation". Unfortunately I've lost the link and can't find it by searching Danfoss US. Perhaps someone will re-post the link.

Here's an interesting quote from the document:

"In two-pipe installations a small heat load leads to high temperature drops, while a small heat load in a one-pipe installation involves small temperature drop, since all the water is led through the bypass. This means that the flow temperature in a one-pipe installation must generally be as low as possible--depending on the local requirements--since otherwise the return temperature becomes too high, leading to excessive heat loss from the pipes. Regulation of a one-pipe installation thus requires the use of a highly accurate, central regulation valve, which in practice is very difficult because of different time constants. A two-pipe installation, on the other hand, has a positive feature in that if the flow temperature is too high, this simply results in the radiator thermostats regulating even faster and thus even more energy-economically."