Swimming Pool Blog
by Mark Garcia March 04, 2014
Installing a Variable Speed Pump
By now I am sure that you have heard of the new technology known as Variable Speed Pool Pumps - with a permanent magnet induction motor, they run cool to the touch, and are quieter than standard motors. And the best part is - they can save over 75% off your pool pump electrical bill. In some states with expensive electricity, this can save hundreds of dollars per year, or more for larger pools or fountains running 2 or 3 hp standard pumps.
But what about installation - is it complicated? Naaa, aside from programming your new pump, which can take the place of a time clock, a VS pump installs in the same manner as a regular pump. Not so with 2-speed pumps, which require a 4th wire - the low speed wire, and a new time clock. VS pumps don't have an extra wire, just two power leads and a ground wire. They operate on 220V, or 110V per wire.
I'll try to get a video together on the process when the weather warms up, but for now, here's a description of the 3 steps involved in installing a variable speed pool pump - Plumbing, Wiring and Programming.
PLUMBING FOR A VS POOL PUMP:
Start by cutting the pipe that comes in, and the pipe that goes out of the existing pump. This will allow you to move the pump to a better position to remove the wires coming into the rear of the motor (shut off power first at the breaker and the time clock), and the bonding wire. After cutting, use large channel pliers or a strap wrench to remove the threaded fittings in the pump. You may reuse these fittings on your new pump, or use new fittings.
VS Pumps come ready to accept 2 inch pipe, and with the proper fitting, can also accept 1.5", 2.5" and 3" pipe. Some VS pumps, such as the Hayward Eco Star, come with Union connections to make future service removal easy. If you use these connections, make sure that you use a cement suited for CPVC.
If the new pump is too low or too high, you may be able to adjust the pump foot, or the base under the pump to raise or lower the pump to best match the incoming and outgoing pipes. The incoming pipes can also be raised if needed, by using couplings to extend the pipes. In some cases, new plumbing will need to be run all the way to the filter, but it's not that far. Try to plumb in straight runs, with as few 90's and 45's as possible, which add resistance to the system.
WIRING FOR A VS POOL PUMP:
As mentioned earlier, the wiring for a variable speed pump is no different from a regular pump. First, make sure that all power is off, at the timeclock and the breaker. Use a test meter to verify. Attach a straight conduit connector to your new VS pump, on the junction box mounted on the motor. Connect the ground wire first, and then connect your two power leads (110V ea) to the two terminals labeled for incoming power. If unsure which connection to make consult your owner's manual.
Here's a couple of shots of the wiring for VS pumps. The Hayward Eco-Star is pictured on the left and the Pentair Intelliflo is on the right. After tightening down the wires, secure the cover plate and fill the pump with water - we're almost ready to test!
PROGRAMMING A VS POOL PUMP:
If you have ever programmed a TV universal remote, or set up a home thermostat - the menu driven application will feel very familiar. You'll configure the pump address (like an IP address), then set time, AM/PM, Langauge. Then you can set minimum and maximum speeds, and a ramp speed, or how fast the motor ramps up. Then you can set timer modes, or running schedules, and set special cleaning cycles or freeze protection. You can even set a password and engage an auto-lock to prevent someone from tampering with settings.
In most cases, programming for a variable speed pump will take no more than 10 minutes. If you are interfacing with an external controller, then you can expect more time in wiring the pump up to the controller for operation at the main control panel.
Thanks for Reading!