EXT Pond Pumps

Water needs to be introduced into the suction line before starting the EXT pump for the first time.  The EXT Pump Plumbing Kit includes a plumbing tee with a threaded cap on the discharge side that is used as a priming port to add water to the suction line.  Close the ball valve (turn valve perpendicular to PVC pipe) when filling to make sure the water being added fills the pump volute and suction line. The EXT Pump Plumbing Kit includes a 3″ swing check valve located beneath the surface of the water.  This check valve holds the water in the suction pipe.  Once filled the threaded cap can be replaced back onto the tee and the pump can be powered on.  The ball valve can then be opened to allow the flow of water to begin.  Once primed, the pump can be turned on and off without priming as long as water remains in the suction line. 

The suction line needs to be filled with water via the priming port.  Make sure that all plumbing connections are tight, including the threaded union located above the check valve.  Any air leaks in one of these connections can cause the pump to not prime properly.  Make sure the check valve is free and clear of debris and is in a vertical position that allows the internal flapper to seal and hold the water in the pipe when the pump is not operating.

We recommend trying to keep the length of the 3″diameter suction line at 10 feet or less and the distance from the surface of the water to the pumps inlet at 3 feet or less.  While increasing these distances is possible, it will make it easier to prime the pump and maintain the prime when the plumbing distance and intake height is minimized. 

One of the advantages of the Aquascape EXT pumps is that the motor runs at a very low RPM compared to other external pumps that are used for swimming pool type applications.  This allows the EXT pumps to operate quietly. 

The EXT pumps can be exposed to rain and snow, however they cannot be submerged in water.

There are several different ways to disguise the pumps along the pond edges.  You can build an enclosure out of wood, stone, or other natural materials. You can use a prebuilt metal enclosure or a fabricated fake stone cover.  You can also use landscape plantings to help disguise the location of the pumps. The EXT pumps include a totally enclosed fan-cooled motor so it is important that the structure or cover used has ventilation to allow the pump access fresh air circulation.

The EXT 12000 Pond Pump includes a 10 foot electrical cord with a 115V grounded plug.  This cord can be removed and reconfigured by a qualified electrician to meet the electrical requirements of the project.  The other EXT pumps do not include an electrical cord due to the pump’s electrical requirements and should be configured and installed by a qualified electrician.  

A variable frequency drive (VFD) is a controller that varies the voltage and frequency (hertz) of the pump’s motor allowing you the ability to control the pump’s water flow rate.  The VFD can be used to schedule the pump to slow down during certain hours of the day to conserve electricity and speed up during other hours, such as after work or on the weekends when a larger flow over the waterfalls is desired.  It can also be configured to slowly ramp up pump speed helping to reduce stress on the plumbing fittings during when the pump is starting up.

The VFD can only be used with a 3-P (3-phase) version of the Aquascape EXT pumps. VFDs require 220-480V 3-phase power, which is typically available on commercial installations, but not on residential installations.  The VFDs can operate on single-phase residential applications as long as 220V single-phase power is available.  

Remove the threaded collar on the union located on the suction side.  This will allow the water to drain from the pump. There is a drain plug located below the 3″ pump intake that can be removed to further drain any remaining water from the pump volute.

The suction line needs to be filled with water via the priming port. Make sure that all plumbing connections are tight, including the threaded union located above the check valve. Any air leaks in one of these connections can prevent the pump from priming properly. Make sure the check valve is free and clear of debris and is in a vertical position that allows the internal flapper to seal and hold the water in the pipe when the pump is not operating.

Note: If the initial attempt to prime the pump fails, you must turn off the pump and allow it to cool down for a few minutes before attempting to prime again. This prevents the risk of damaging the mechanical seals through thermal shock during another priming attempt (suddenly introducing cold water to the warm mechanical seal surface).