Sanremo ZOE SAP Bedienungsanleitung Seite 28

ENGLISH
Warning – correct use of rotary pumps
1-Proper Alignment of Pump and Motor
On occasion the noise of a motor-pump assembly is caused by a poor alignment.
When the coupling between motor and pump is rigid, the pump rotor and the motor rotor may be out of axis. If this condition is maintained over
time the most likely damage is seizure of the pump.
An efficient solution of this problem is the use of an elastic coupling between pump and motor. Fluid-o Tech supplies an optional kit code N. 10051020.
2-quality of Water.
Tight mechanical tolerances of components and materials used for rotary vane pumps require a very clean water, free from suspended particles.
Sand, deposits on connecting pipes or the resins of the sweetener, when flowing through the pump, may scratch graphite parts causing problems
of insufficient pressure and flow rate. If a closed loop hydraulic circuit is not available to guarantee a clean water and no sources of contamination
Fluid-o-Tech recommend to install a 5-10 micron filter between the sweetener and the pump.
Recommended filter: food approved polipropilene wire cartridge. Keep the filter clean.: an upstream dirty filter will create cavitation and the pump
will break shortly (see section 4).
3-Dry operation
Rotary vane pumps may operate in dry condition only for a very short time- few seconds!
Without a proper water cooling the temperature of the mechanical seal will increase very quickly with resulting breakage. The most likely impact is a
remarkable leak visible from the four drain holes close to the motor clamp . For potential lack of feed from city water line Fluid-o-Tech recommend
the installation of a minimum pressure safety switch upstream from the pump.
In case of feed from a tank install on the tank a minimum level switch.
4-Cavitation
Cavitation shows when feed flow rate does not match the pump design requirement: most frequent causes are dirty filters, small diameter pipes,
more users on the same line.
Opening of the safety valve (generally installed upstream from pump and filter) must happen
before the pump start up. This will avoid cavitation. For the same reason closing of the safety valve must be delayed after the pump shut down.
The most noticeable effect is an increase of noise. If cavitation continues the impact is the same as of dry operation.
5-Back Feed of Hot Water
If a non return valve between the pump and the hot water vessel is defective the pump may come in contact with hot water(90-100°C). Dimensional
variations of components will cause seizure of the pump.
6) Wrong connections
Pumps connectors are 3/8"NPT(conical) or 3/8" GAS(cylindrical).
Connectors with thread different from the recommended type are occasionally used. Sealing is made with a glue or with teflon tape. If the connector
is forced it is possible to create beards; if excess sealing glue is used the extra quantity of glue may enter into the pump body.
In both cases it is likely to create a damage.
7) Pressure strokes
To avoid pressure strokes opening of solenoid valves installed downstream must happen before the start of the pump. For the same reason closing
of the valve must be delayed after stopping of the pump. A pressure stroke may break graphite parts and damage mechanical seal causing blockage
of the pump and leaks.
8) Handling
A crash on the floor may create deformations that will jeopardize the tight mechanical tolerances of the pump components. For the same reason be
very careful when clamping the pump to mount or demount connectors.
9) Scale build up
Scale deposits will quickly show on inner components when using hard water, not sweetened with ion exchange resins.
Scale formation increases when the pressure relief valve is used as flow rate regulator: the rate of scale deposition increases with increasing of
closed loop circulation. Scale deposits cause an increase of torque, occasional seizure of the pump or a reduction of operating pressure because
the pressure relief valve cannot work properly.
To minimize this problem Fluid-o-Tech suggest to use pumps with flow rate matching the hydraulic circuit features.
In some circuits it is advisable to periodically remove scale with a chemical treatment.
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