Pentair ONGA IMH750 User manual

OWNER`S MANUAL
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Should the installer or owner be unfamiliar with the
correct installation or operation of this type of
equipment, contact the distributor or manufacturer
for correct
advice before proceeding with installation
or operation
of the product
We recommend, for additional protection, the pump
to be supplied from socket outlet protected by a residual
current device - RCD (also known as an earth leakage
circuit breaker - ELCB) with a maximum rated residual
current of 30mA.
IMH RANGE
HORIZONTAL MULTISTAGE
CENTRIFUGAL PUMPS
IMH750 IMH1100 IMH2200

Technologically advanced solutions for
moving and treating water in the Home,
Garden, Pool and Spa.
Innovative Stock and Crop water
management solutions for Primary
Industries.
Water movement products for Building
services, Emergency services and
Original Equipment Manufacturers.
Relax - you’ve bought an ...
Congratulations on your decision to purchase an Onga product.
Onga is one of the best know brands in its field, with a proud local
and international reputation.
Onga is a brand for reliability, value for money and technological
innovation. You will find an Onga product wherever people need to
move water in 3 broad markets covering:
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1. Continual P roduct I mprovement
We employ the best engineers both in Australia and
around the world to develop new and better ways to
take water further.
2. Operational E xcellence
There is only one standard that we set ourselves for both
product quality and the quality of our service. That standard
is excellence... to have no-one better than us at what we
do... nothing short of that is acceptable. Our commitment to
quality is reinforced with our ISO 9001:2000 accreditation.
3. A Fair Price
Onga products are neither the cheapest nor the most
expensive in their fi
eld. Our products do, on the other hand,
always represent very good value for money; they always
have and they always will.
4. Our Team of Dealers
Our hand picked authorised Onga dealer network throughout
Australia and worldwide are second to none. We invest
considerable time and resources training and supporting
them through the Onga Training Academy.
2
®
ONGA

Table of Contents Page
Model D ata 4
Application 5
Installation 6
Operatio n 11
Service a nd M aintena n c e 13
TroubleS hootin g 14
Warrant y 15
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Motor
(W)
IMH750 750
IMH1100 1100
IMH2200 2200
Technical Information
Inlet( Su c t i o n ) : 1”B SPF (IMH750&1100)
Outlet( Discharg e ) : 1”B SPF
Water Temperature Range: 1º - 50ºC
IP R ating : IP55
Electrical Supply: 230V +10%, -6%, 50Hz single phase
Maximum Ambient temperature: 40 ºC
1/4”
1 B SPF (IMH2200)
(IMH750&1100)
1/4”
1 B SPF (IMH2200)
Model

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Application
Onga IMH Series pumps are suitable for pumping clean water in a
domestic water systems, small irrigation applications, and as pressure
booster pumps. The strength of the stainless steel pump casing coupled
with the impervious nature of the stainless steel impeller and diffuser
make it ideally suited for most potable water pumping applications.
NOTE: Consult your local Onga dealer for information regarding the suitability of
each IMH pump in an automatic pressure system prior to installation.

Installation
The electrical installation shall be in accordance with the national
wiring rules (AS/NZS 3000) for class 1, IP55 rated products.
These instructions are a guide only. Users not familiar with
pumping equipment should seek advice from people experienced
in pump equipment and installation.
Freezing conditions will damage the unit, because when water
freezes it expands. Ensure that the pump is located so that it is
not prone to freezing, or ensure that the product is disconnected
and dried of water during cold conditions.
IMH pumps are electrically connected. Ensure that they are
switched off and unplugged from socket outlet during installation
and any subsequent service work.
The pump is designed to be used with clean water in a residential
application. Do not use it with alternative fl uids, abrasive,
corrosive or explosive fl uids. Do not install or operate your pump
in an explosive environment or near combustible matter.
Incorrectly installed or tested equipment may fail, causing severe
injury or property damage.
Fire and burn hazard. Modern motors run at high temperatures. To
reduce risk of fi re, do not allow leaves, debris, or foreign matter
to collect around the pump motor. To avoid burns when handling
the motor, let it cool for at least 20 minutes before trying to work
on it. Automatic thermal overload cut-out protects the motor for
heat damage during operation and it will restart without notice
when the motor cools down.
The pump is not intended for use by young children or infi rm
persons without supervision. Young children should be supervised
to ensure that they do not play with the pump.
Read the following instructions in this owner’s manual when installing and
operating equipment.
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1. Preparation for Installation
Inspect your pump for shipping damage. Report any damage to your Onga
stockist. Make sure the suction piping is free of air leaks and is laid so that
there can be no airlocks.
Warranty of these pumps is void unless they are operated in accordance with
this owner’s manual.
2. Pump Protection
The pump should be protected from the weather, floods, chemicals, dust,
vermin, insects etc. It is highly recommended that the pump be housed in a
weather proof, well vented enclosure. If the pump is not adequately housed
the warranty may be deemed void.
3. Pipe Installation
Pumps can be damaged if care is not taken when connecting pipes. Pipes
should be supported so that the pump casing is not strained by the weight
or misalignment.
We recommend the pump and pipe are coupled using fl exible type polythene
pipe, rubber hose or a multi-directional barrel union. This union coupling can
also be used to remove the pump for service should it be necessary without
having to cut pipes.
Pipe fittings should be carefully screwed into the pump making sure not to
cross-thread or overtighten. We recommend the use of a moulded pipe fi tting
to connect to the pump as this avoids possible damage to the pump threads
and unnecessary replacement of parts.
For best results use teflon tape to seal the joint. Satisfactory sealing can be
achieved by hand tightening fittings ensuring that no leaks are evident once
under pumping pressure.
4. Locating the Pump
Find a location for your pump as close to your water source as possible.
Ensure that this location is on a seperate footing from your home. To do this
you can mount the pump on a concrete tile or concrete base.
5. Power Source
Arrange for an electrician to install an outdoor 10A or 15A GPO electrical outlet
near the pump if there is not one there already. 15amp is required for the
IMH2200 pump.

6. Suction
This is the most important part of the installation as errors will cause signifi cant
problems for the system in performance and longevity.
IMPORTANT: A gate valve must be installed at the tank outlets.
Installations where the tank base is level with the pump
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Min 100mm
100mm
In Line Filter
500 Micron
House Wall
Recommended Length 150mm
Barrel Union
Solid Base
Non-Return
Valve
Gate
Valve
Min 100mm
100mm
In Line Filter
500 Micron
House Wall
Recommended Length 150mm
Barrel Union
Solid Base
Gate
Valve
Installations where the tank base is below the pump

To maintain optimum performance from your pump, the suction pipe should
be:
- Kept to the shortest distance practical, but not shorter than
- Re-enforced crush resistant (non-collapsable) hose or pipe.
- All fittings should be air tight.
- Pipes should be equal to or larger than the diameter of the
suction/inlet p ort.
- Ensure that the suction pipe is completely full of water.
Consult your Onga dealer for information regarding the suitability of each
IMH pump in an automatic pressure system prior to installation.
7. Discharge
The length and diameter of the discharge hoses/pipes will affect the pressure
and flow rate at which your pump operates. Pressure ratings of all components
must exceed the maximum pressure of the pump by an appropriate safety
factor. All pipework should be supported independently of the pump.
8. Pump Priming
Ensure that there is at least 200mm of water in your tank, (i.e. that the tank
outlet is covered, and the pump will not draw any air into the system). Open the
gate valve on the tank. Check for any leaks, and repair these if necessary.
If no leaks are present, remove the priming plug to open the priming port on
the top of the pump case.
If the tank is above the level of the pump, water will start to run out of this
port. Replace the priming plug carefully. Your pump is now ready to run.
(Note: If a check valve is installed in the suction line, water may not fi ll the
pump. If this occurs, follow the instructions below).
If the tank water level is below the level of the pump, you will need to fi ll the
pump body and suction line. Remove the priming plug and fi ll the pump body
and suction line using a funnel.
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the recommended length.
The pump may require to be primed a number of times during start up to
ensure all air is expelled.
PRIMING
PLUG

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inserting the plug into the suitable socket outlet.
The socket outlet shall be in a dry and flood free location; preferably do not
use extension cords for this very reason and because they can cause voltage
drop.
Supply voltage outside limits specified in Model
Data can cause the motor to overheat leading to overload
tripping, reduced component life or seriously
damage pump and voids warranty.
WARNING
Hazardous voltage.
Can shock, burn, or
cause death.
9. Electrical
The pump is supplied with a power supply cord and standard Australian 10
or 15 Ampere plug and cord. Connection to the power supply is a matter of
We recommend, for additional protection, the pump
be supplied from the socket outlet protected by
a residual current device - RCD (also known as an
Earth Leakage Circuit breakers - ELCB) with a
maximum rated residual current of 30mA.

Operation
The pump operator or owner must be provided with this owner’s
manual. This must be read before operation, and followed during
operation.
Ensure that your pump is filled with water before operating.
The pump is designed to be used with clean water in a residential
application. Do not use it with alternative fl uids, specifi cally
abrasive, corrosive or explosive fluids. Do not install or operate
your pump in an explosive enviroment or near combustible
matter.
Fire and burn hazard. Modern motors run at high temperatures. To
reduce risk of fire, do not allow leaves, debris, or foreign matter
to collect around the pump motor. To avoid burns when handling
the motor, let it cool for at least 20 minutes before trying to work
on it. Automatic thermal overload cut-out protects the motor from
heat damage during operation and it will restart without notice
when the motor cools down.
1. Start-up / Operation
Ensure you have primed the pump correctly. (Instructions on priming the pump
can be found in the installation section under Point 8. Priming Pump).
Note: If the pump is not used for a long period of time, repeat the priming
procedure before start up.
Start the pump and check rotation of the motor. It rotates in a clockwise
direction when viewing the fan through the cowl behind the motor.
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Failure to do so may result in damage to the pump seals and
may void warranty.

2. Pressure Vessel
The Onga IMH series of pumps are supplied with a pressure vessel to
assist the variable speed drive controller. The vessel needs to be
pressurised to 70% of the set pressure of the pump.
Operating set point of pump: 400kPa
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Example:
Operating set point of vessel: 280kPa (70%)
The pressure vessel can be pressurised using a hand pump or portable
air pump.
Failure to pressurise the pressure vessel may result in the pump
continuing to run or cycle on and off. This will cause damage to the
pump and controller, and may void warranty.
Pressure Vessel Maintenance: the air pressure in the pressure vessel
can decrease over time, therefore it is highly recommended to check the
air pressure every 6 months.

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Service and Maintenance
Pumps should only be serviced only by qualifi ed personel. For
best results, use only genuine service parts. Be sure to prime
pump before starting.
To avoid dangerous or fatal electrical shock, turn OFF power to
pump and remove plug from outlet before attending the pump.
RCD tripping indicates an electrical problem. If RCD trips and will
not reset have a qualifi
ed electrician inspect and repair electrical
system and/or pump.
If service is required to the power supply cord and/or appliance
connectors, they must be replaced with the specialised cord
assemblies by Pentair Water service agent or similarly qualifi ed
personnel in order to avoid a hazard.
Liquid may be HOT, release pressure with care before
servicing.
1. General Care and Maintenance
Under normal conditions the Onga IMH series of pumps requires only minimal
attention. A six monthly check of the general condition of the pump and
In order to prevent possible failures, it is advisable to periodically check the
pressure supplied and power absorption is also carried out. A decrease in pressure
is a symptom of wear. An increase current absorption is a sign of abnormal
mechanical function in the pump and/or motor. If these symptoms occur, take your
pump to your nearest service agent for inspection and repair.
plumbing is recommended.

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Symptom Cause Remedy
Pump does
not operate
and motor
does not run.
No Electricity
Verify presence of electricity.
Not Plugged in correctly Ensure pump is connected properly
Circuit breaker activated Reset circuit breaker
Pump hums
and the
thermal relays
cut in and out
Pump is clogged by
debris
Clean suction pipe and foot valve/
strainer. Clean the pump by flushing
with water. Remove the priming and
drain plugs. If the pump cannot start
after several flushings, it must be
dismantled and cleaned.
Pump
operates but
delivers no
water.
Pump is not filled with
water.
Fill the pump with water (see
installation section - Priming Pump )
Suction head is too high Reduce the suction head
Foot valve/strainer is not
submerged enough
Make the suction pipe longer (max 8
metres)
Suction pipe is taking
in air
Check the suction pipe and joints for
air leaks.
Suction pipe/strainer or
non-return valves are
clogged with debris
Clean the suction pipe/strainer or
non-return valve
Pump is clogged with
debris
Clean the pump of debris
Reduced
performance
Suction head is too high Reduce suction head.
Foot valve/strainer only
partially submerged
Lengthen suction pipe.
Pump shaft seal is worn
or damaged
Replace defective parts
Pump is partially blocked
with debris
Remove debris and flush pump with
clean water
Should problems persist, contact your nearest Onga Service Agent.
Troubleshooting

L100367 0917
IMPORTANT
Please attach your sales invoice/docket here as proof of purchase should warranty service
be required.
Please do not return Warranty - Retain for your records.
Purchased From .............................................................................................. ................. .......
Purchase Date..................................... Serial No.............................. Model No........................