112 POULTRY LABORATORY GUIDE 



size of the chimney, its location, and the dam- 

 pers which control the draft. Is there any 

 method of cleaning the heat flues? Examine 

 the grate construction, also the method of shak- 

 ing. Is it cUnker proof ? 



Find the point at which the cold water is taken 

 into the system, also the point at which the hot 

 water leaves the boiler, as well as the point where 

 it enters on returning. Also notice the presence 

 of a thermometer if it is a hot water system, to 

 determine the temperature of the water. If 

 steam, note the presence of a pressure gauge. 



Follow the course of the heated water through 

 the various coils, noting the presence of valves 

 controlling same, also the presence at the highest 

 point in each coil of a small pet cock to allow the 

 escape of steam and compressed air which often 

 forms at these points. 



Note the presence of an expansion pipe and 

 tank which keeps a constant supply of water in 

 the pipes all the time, emptying or fiUingupas 

 the water cools or becomes hotter. Do the hot 

 water or flow pipes run level on leaving the 

 boiler, or do they slope ? If so, which way and 

 why ? Measure the size of pipes and determine 

 the radiating surface required. 



In firing a hot water heater, observe the 

 following facts. 



