Finally , the last calculation and the temperature entering my radiant panel , Z5 , is 170 ° F .
( 15.5 gpm x 170 ° F )[ 2635 ] + (. 5 gpm x 160 ° F )[ 80 ] = 2715 ÷ 16 = 170 ° F
Now , we would just have to wire this all up . Using a TACO ZVC404-EXP Zone Valve Control , Figure 12 , the wiring becomes easy , and I can tell you these make life a lot simpler which is why
Figure 12
Figure 10 Figure 11
The temperature leaving the panel is 164 ° F . Not much temperature drop and way over my desired temperature of 100 ° F and remember this is on a ‘ design day ’. What about the rest of the heating season ? So , what do we do ? Well , the simplest solution is another mixing valve , Figure 4 . In Figure 10 we have what the piping should look like for the radiant loop , Z5 . The water now leaves the Primary loop through the double tee fitting , Figure 11 , enters the hot side ( h ) of the mixing valve and mixes with the cold side ( c ) of the Secondary loop and enters the circulator from the mixed side ( m ) of the mixing valve . The water is pumped through the Secondary loop and returns to the double tee fitting and re-enters the Primary loop while supplying the mixing valve cold side ( c ).
You must also make sure a few rules regarding radiant loop mixing valves are observed :
1 . That there is no more than 4 pipe diameters between the tees in the primary loop and the double tee fitting , Figure 11 , ensures this .
2 . That there are at least 6 pipe diameters on either side of the double tee fitting to prevent the primary pump from pushing water into the Secondary loop .
3 . That there is at least a one-foot drop on the return pipe and mixing valve cold side ( c ) to create a thermal trap and protect the mixing valve and prevent unwanted heat siphoning .
there is one in my own home . The wiring is shown in Figure 13 .
I have four zones using zone valves for control , a primary circulator , a secondary circulator and my indirect circulator all communicating with each other and my boiler operating control through this panel , easy-peasy , Figure 14 . Thanks for reading this and see ya ! l FON
Figure 13
Figure 14
* George Lanthier is the owner of Firedragon Academy . His website and contact information can be found at www . FiredragonEnt . com
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