Davey HP/T & HS/T Pressure Systems with Torrium2 - Manual (Page 6)

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Where to use Check Valves and Foot Valves
The Torrium2 ® controller fitted to HP models has an inbuilt non-return (check)
valve fitted. HS models have an inbuilt non-return valve cassette fitted in the pump
suction port. In flooded suction installations there is no need to have a suction non-
return valve.
In suction lift installations a footvalve will normally be required for the pump to
retain prime.
In some suction lift installations there may be good reason to remove the inbuilt
check valve to ensure that the discharge pressure is also applied to the suction line
and footvalve. This could be where the suction line was very long or where there
was concern regarding a leaking footvalve. This may not always be applicable and
it is acceptable to retain the inbuilt check valve in the Torrium2 on suction lifts with
good suction plumbing.
Should the inbuilt check valve be removed though, an additional accumulator
should be fitted to the Torrium2, or discharge pipework as applicable, to ensure the
pump is not cycled on shut down. The size of this accumulator will depend on the
size, length and type of pipe used on the suction.
Torrium2 Check Valve Removal
Use unions at pipe connections to enable easy removal
and servicing. Use sufficient tape to ensure airtight seal
and hand tighten only. To prevent strain on pump threads
always support heavy inlet and outlet pipes. If there is a
likelihood the water supply may contain solid particles such
as pieces of plant or vegetable matter, a filter should be
installed before the pump to avoid blocking of water ways.
Lay suction pipe at a constant gradient to avoid air pockets which may reduce
pump efficiency.
NOTE: Suction leaks are the largest cause of poor pump performance and
are difficult to detect. Ensure all connections are completely sealed using
thread tape only.
Flexible pipe should be considered to allow for movement between
building, pump and/or water supply. Braided hose, reinforced hose or
polythene pipe are suitable.
Do not use pipe thread sealing compounds on any part of this pump. ONLY
use Teflon sealing tape.
Remove priming cap and
turn over cap. Lugs on
cap will engage check
valve to unscrew.
Extra Draw-off Capacity
The Torrium2 ® controller has an in-built accumulator which will accommodate small
leaks. In some applications it may be appropriate to install additional accumulator
(Supercell pressure tank) capacity. These applications includes:
• Long suction lines (see Suction Lines / Lift)
• Low flow appliances connected to the pump, such as evaporative air
conditioners, slow filling toilet cisterns, etc.
Any additional accumulators can be installed either in place of the priming
plug (see Figure 1) for tanks up to 20 litres total capacity, or for larger tanks,
downstream of the controller (ie. between the controller and the first outlet).
Where extra draw-off capacity is utilised the additional pressure tank should have a
pre-charge of 70% of the maximum system (shut-off) pressure.
Evaporative coolers, RO filters and extra draw-off
capacity
Where a Torrium2 ® equipped pump is required to supply water to an evaporative
cooler, reverse osmosis (R.O.) filter or similar low flow device, the Torrium2 ® will detect
the limited demand. This will result in the Torrium2 ® adapting to the slow demand. The
pump start pressure will be allowed to drop to a lower cut in pressure each time low
flows are detected. To provide the maximum draw-off from the additional pressure tank,
the tank’s pre-charge should be set at 45% of the pump shut-off pressure.
If normal flow is required from your system, Torrium2
® will initiate instant start.
Fit the Supercell pressure tank (up to 20 litres total capacity) to the tank connection/
priming port with thread tape and pipe socket. Firmly hand tighten. For larger tanks,
these should be installed downstream of the controller.
NOTE: If fitting a tank to the priming port, you may require a 1”
BSP socket, since both Torrium2 ® prime port and tank are 1” male
threads.
DO NOT USE THREAD SEALING COMPOUNDS, HEMP OR PIPE DOPE!
HS Inlet Check Valve Removal
If your installation requires the removal of the HS pumps inbuilt
check valve or the inbuilt check valve requires removal for
servicing, this can be achieved without difficulty. The inbuilt
check valve is a cassette design, which is screwed in through
the suction inlet.
Removal of the check valve cassette is achieved by inserting
any suitable tool (eg. a pair of pliers or the handle from an adjusting spanner) into
the inlet. The check valve cassette has various ribs and recesses to allow a variety
of nonspecific tools to be used in the removal or insertion process.
Installations with flooded suction require a gate or isolating
valve so water supply can be turned off for pump removal
and servicing.
Abrasive Materials
The pumping of abrasive materials will cause
damage to the pressure system which will then not
be covered by the guarantee.