Pulsafeeder PULSAtron Series T7 - Manual (Page 13)

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USE AN ANTI-SIPHON VALVE IN THE DISCHARGE LINE whenever the fluid pressure in the discharge line is below
atmospheric pressure. This can occur if the injection point is on the suction side of a water pump or against a "negative"
head such as when feeding down into a well.
4.2 Piping
Use provided tubing of specified size for connection. Connect tubing securely to prevent leakage of chemical and the
entrance of air. Since plastic nuts are used for fittings, they should not be tightened excessively (i.e. hand tighten only).
NPT suction and discharge valves must NOT be over tightened. Hold fitting in place while adding piping and fittings. NPT
suction and discharge valves should only be tightened 25 to 35 in. lbs. (4.5-6.3 kg/cm).
If the air bleed valve assembly is being used, a return line (tubing) should be securely connected and routed back to the
storage tank. To avoid possible injury from chemicals do not attempt to prime using a bleed valve without
installing a return line.
When pump is shelf mounted or top mounted on tank, suction tubing should be kept as short as possible.
To maintain metering performance, a backpressure/injection valve is provided. The spring in the standard injection valve
typically adds 17 - 20 PSI (1.17 - 1.38 BAR) to the line pressure, with the exception of the H8 pump, which adds 8 - 10
PSI (.55 - .69 BAR). The injection valve must be installed in the discharge line. Best practice is to install the injection
valve at the point of chemical injection.
If the discharge tubing is going to be exposed to direct sunlight, black tubing should be used instead of the standard white
translucent tubing supplied with each pump. To obtain, contact supplier.
To prevent clogging or check valve malfunction always install a strainer assembly to the end of the suction tubing (Figure
5). This foot valve/strainer assembly should always be installed 1 to 2 inches (2-5 cm) above the bottom of the chemical
tank. This will help prevent clogging the strainer with any solids that may settle on the tank bottom. The chemical tank
and foot valve/strainer should be cleaned regularly, to ensure continuous trouble free operation. If the chemical being
pumped regularly precipitates out of solution or does not dissolve easily or completely (e.g. calcium hydroxide), a mixer
should be used in the chemical tank. These are readily available in many motor configurations and mounting. To obtain,
contact supplier.