How to install variable speed pumps
Installation of a new pump often requires removal of an existing pump. Removing and replacing pumps is not difficult, but preparation can make the job quicker and easier. Having the appropriate tools on hand will make the job go faster. Tools needed include:
• Electrical meter
• A pipe cutter such as a reciprocating saw, hack saw, or a ratcheting PVC cutter.
• Miscellaneous tools such as screwdrivers, wire cutters, wire strippers, wrenches, pliers, and sand paper.
• PVC materials such as 90° and 45° elbows, unions, couplings, valves, pipe thread compound or Teflon tape, PVC glue and primer. For common PVC fittings, schedule 40 or 80 pipe is recommended. Note the threaded fitting size of the replacement pump housing. Most are 2” male pipe thread and some pumps come with the threaded fittings.
• Prior to exchanging pumps, ensure that the electrical supply voltage as well as wire and circuit breaker size are compatible with the replacement pump.
• Measure the replacement pump dimensions and compare these to the existing pump. Certain critical dimensions such as the suction port height and distance from pump suction port to discharge port can vary between the pumps. It’s a good idea to plan ahead for how the replacement pump will fit and where it would be best to cut pipes. Finally, ensure that sufficient wire and conduit is available.
When these preparations are complete, the pump can then be removed.
If the existing pump is not in an ideal location, service techs may want to relocate the new pump.
For example, if it is not already the case, the pump should be installed as close to the pool and spa as possible. Short and direct suction and piping returns minimize friction loss and will improve the pump’s efficiency.
In most cases, the pump should be installed a minimum of 5 feet from the inside wall of the pool, and not more than 8 feet above the water level or three feet below.
The pump should be installed in a sheltered but well ventilated location protected from excess moisture.
For future maintenance needs it is best to install the pump with a rear clearance of at least 3 inches.
• To remove the old pump, begin by disconnecting electricity to the pump at the circuit breaker.
• Ensure that the pump is not receiving electricity with an electrical meter.
• Disconnect electrical wires at the pump junction box.
• Use pipe cutters or a hacksaw to cut the discharge and suction pipe.
• The pump can then be removed.
• Before installing the new pump, make sure that the area is clean. Place the new pump on the pad so that the suction and discharge pipes are aligned. It may be necessary to use shims to compensate for varying pump heights, but be sure to create a level and stable surface.
• Install threaded fittings in suction and discharge ports. Be sure to use thread sealant or pipe glue in order to keep the fittings leak free and well connected. Allow these fittings to dry before introducing water.
• If space allows, prior to any elbows, valves or tees, install a straight length of pipe prior to the pumps inlet that is five times the diameter of the pumps suction port. For example, if the suction pipe diameter is 2 inches, a straight 10 inch pipe is required before an elbow. This will help the pump prime faster and last longer.
• Above all, don’t install 90° elbows directly into the pump inlet.
Larger pipe sizes improve the pumps performance.
• Reconnect the electrical conduit and wires according to code. Be sure to connect the ground bonding wire to the pumps bonding lug. Make sure all electrical connections are clean and neat, with the wires cut to the appropriate length so they do not overlap or touch.
• Bond the motor to the pool structure. UL requires the use of a solid copper bonding conductor no smaller than 8 AWG. This wire should be run from the bonding lug to the pool bonding structure.
• The pump should be permanently connected to either a circuit breaker, 2-pole timer, or 2-pole relay.
When connecting the pump to an automation system, continuous power must be supplied to the pump by connecting it directly to a circuit breaker.
Prior to system start-up, the pump must be manually primed and evacuated of air. Air that has entered the system during the removal and installation process can become pressurized and explode. Vent the air through the filter’s manual relief valve.
Running the pump dry can also damage the mechanical seal. • To prime the pump, remove the strainer pot lid and fill the pump with water until the water level reaches the suction port. Replace the strainer pot lid. Begin by opening the manual relief valve on top of the filter and start the pump. Bleed the air from the system by allowing it to escape from the filter until a steady stream of water comes out. Finally, close the manual relief valve.
• Finally, the pump must be programmed in order to get proper filtration and circulation while using the lowest motor speed.
• It should be set to operate at a speed that will turn over the pool volume at least once every 24 hours, depending on the amount of debris and bather load. The turnover time should not be less than 6 hours for normal operation.
The flow rates should be set as low as is possible to accomplish a given task to maximize energy efficiency.
The start-up flow rate will probably need to be higher, however, to prime the pump and vent the air from the filter, as well as other start-up tasks like filling up solar panels.
New Variable-Speed pumps are equipped with programmable setting for different operations such as normal filtration, extra filtration, jets, water features, and pool cleaners.
It’s a good idea to have these programmed in advanced to provide the pool owner with modes that temporarily override normal filtration flow rate.
This is especially useful in the event of a storm or pool party.
To ensure customer it’s always a great idea to familiarize to pool owner with the new pump’s functions, operation, and programming.
Furthermore, if the pool owner does not understand that lowered flow rates directly affect energy efficiency and therefore financial savings, the new pump may not save money after all.
It’s important to educate the pool owner about these things.
Finally, service professionals will want to measure the average energy use of the new pump, especially if the pump was installed due to the service technician’s recommendation.
Compare the energy use of the new pump to that of the old pump and present this information to the pool owner in terms of monetary saving for happy customers.