178 



GREENHOUSES 



i 



Fig. 94. A method of piping a medium size house 



gram A is the flow pipe extending directly 

 up from the boiler; B, B, branch flow pipes; 

 C, C, branch flow pipes extending the length 

 of the house; D, D, distributing pipes at the 

 opposite end of the house; E, E, E, E, the re- 

 turn coils; F, F, F, F, return pipes; and G, 

 expansion tank. 



Valves should be conveniently placed so 

 that any or all of the coils may be cut off in- 

 dividually. They may be placed either in the 

 flow or return pipe, or in both. If there is a 

 valve in both the supply and return from each 

 coil, any one may be repaired in case of an 

 accident without drawing the fire or inter- 



