Near Intersection of I-35 & I-90 Southern Mn. | As far as end of season service, I really don't do anything since I always use pure NH3 without any N-serv or the like.
For preseason service I sometimes (didn't this Spring) remove the flowmeter and disassemble it. The flowmeters used today are very simple. A good cleaning and visual inspection of wear on the houshing bushings and turbine shaft are all that is generally necessary.
Probably the greatest damage done to flowmeters is to run the tanks so low that vapor passes through the flowmeter. This is bad in that the applied rate is incorrect but can also cause damage to the bushings and turbine mentioned above. When a pocket of vapor flows through the flowmeter, the turbine turns at tremendous speeds (this is why you may see an extremely high rate). This will eventually cause wear and failure.
Sometimes a good cleaning is all that is necessary. If there is some debris internally, the turbine may still turn but slower than it should. This will result in the Raven system feeling that it is not applying enough product. The overall effect is that the control valve will be opened more than is necessary and over application will take place.
On the other hand if vapor is present, then the flowmeter turns faster than it should. This results in under application since the system feels that is should close the control valve slightly to apply the correct rate. |
raven accu flow
