PowerSmoke 740 (HV) Operating Instructions
Version 2.0
9. Using a Back Pressure Valve
By principal there are no pumps which lock in normal flow direction;
even not when some provider promise or pretend. This means that a
pump only can increase a volume but never totally lock it. Even the
best pumps tend to pass more or less smoke oil without additional
locking means when powered off.
Through expansion of the tank volume by e.g. heat smoke oil can
reach and flood the muffler. This can be avoided by back pressure
valves which are spring loaded and therefore need some minimum
pressure in order to open at all. Unfortunately even toothed wheel
pumps of good quality generate only low pressure when running dry.
This means a spring loaded back pressure valve of a pump makes
intake more difficult or even inhibits it. It is possible that a new pump
can open such a valve but does not manage it after some hours of
operation anymore.
Therefore we recommend usage of the
PowerSmoke 740 HV
with
integrated back pressure valve or an additional check valve in the
pressure line of the
PowerSmoke 740
.
9.1. PowerSmoke Check-Valve
Our in house developed valve is a cost saving alternative to a
magnetically valve. It can be looped in between the pump and the
muffler without problems. A vent pipe (return pipe) to the tank is
necessary. By using this valve you make sure that the pump does not
pass smoke oil unintentionally. Exact turning on and off is assured.
Longer or permanent smoking when the pump is turned off is inhibited
by this passive valve. Flow rate is only reduced by 5% when using this
valve.
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