Davey HM Series Pressure Systems with Pressure Switch - Manual (Page 4)

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Electrical Power Surge Protection
An electrical power surge or spike can travel on the supply lines and cause
serious damage to your electrical equipment.
If the installation is subject to electrical power surges or lightning we
strongly recommend the use of suitable additional surge protection devices
on ALL electrical equipment.
In accordance with AS 3350.2.41 we are obliged to inform you that this
pump is not to be used by children or infirm persons and must not be used
as a toy by children.
Pipe Connections
For best performance use
P.V.C. or polythene pipes at
least the same diameter as the
pump’s inlet and delivery outlet
openings. Larger diameter
pipe may be used to minimise
resistance to flow when pumping
longer distances.
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.
Do not use pipe thread sealing compounds on any part of this
pump. ONLY use Teflon sealing tape.
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.
Trouble Shooting Check List
A) MOTOR RUNS WHEN SWITCHED ON BUT DOES NOT PUMP.
1. Suction line and pump body not filled with water.
2. Air leaks in suction lines or suction pipe not under water.
3. Air trapped in suction lines (also possible with flooded suction due to
uneven rise in piping; eliminate humps and hollows).
4. No water at source or water level too low.
5. Valve on suction line closed.
B) PUMP SWITCHES ON AND OFF FREQUENTLY (CYCLING).
1. Check that tank air pressure is correct.
2. Leaking taps, float valves etc. Check plumbing.
3. Leaking check valve/foot valve.
4. Pressure Switch may require adjustment to cater for flooded suction
installations – consult your Davey dealer for advice.
C) MOTOR DOESN’T START WHEN SWITCHED ON
1. Power not connected.
2. Supply voltage too low.
3. “Over temperature” cut out tripped.*
4. Motor not free to turn e.g. a jammed impeller.
5. Internal motor fault.
NOTE: For protection, single phase Davey pump motors are fitted with
an automatic “over temperature” cut-out. Constant tripping of this
overload device indicates a problem e.g. Low voltage at pump, excessive
temperature (above 50°C) in pump enclosure.
Care should also be taken when servicing or disassembling pump to avoid
possible injury from hot pressurised water. Unplug pump, relieve pressure
by opening a tap on the discharge side of the pump and allow any hot
water in the pump to cool before attempting to dismantle.
WARNING: When servicing or attending pump, always ensure power
is switched off and lead unplugged. Electrical connections should be
serviced only by qualified persons. If the electrical supply lead of this
pressure system is damaged, it must only be replaced by authorised Davey
service personnel as special tools are required.
NOTE: For protection, the Davey pump motors are fitted with an automatic
reset thermal overload, constant tripping of this overload indicates a
problem e.g. low voltage at pump, excessive temperature (above 50°C) in
pump enclosure.