Pump Parts

Volume 6, Issue 120; 26 Nov 2003

When you turn the tap and nothing happens, well, let’s just say that it’s not a warm fuzzy feeling.

About mid-morning yesterday, the water stopped. This isn’t quite as critical in New England as the electricity going out or the furnace stopping, that can result in really serious damage, but it’s no fun either. Most of use take for granted that turning a tap will produce an effectively endless stream of clear, clean potable water. When you turn the tap and nothing happens, well, let’s just say that it’s not a warm fuzzy feeling.

A quick consult with the plumber brings out the well repair guys. “We’ll be there in about 20 minutes” sure sounded good.

It doesn’t take long to determine that the pump is drawing zero power. With the well-cap open, out comes two-hudredish feet of plastic tubing with a pump and a honking big ¾-horsepower motor on the end of it. (It wasn’t until all the work was done that I realized I’d failed to take any pictures of this process. My bad. Other things on my mind, I guess. But I may get another chance, see below.)

It’s a dead motor. The whole motor/pump assembly is pretty interesting and the guy who pulled it up was happy to rip it apart and show me the pieces.

Pump Assembly
Pump Assembly

The bit in the back is the actual motor. It attaches onto the bottom of the pump assembly, which is the left hand side of the stainless steel tube in the middle. The actual pumping action is achieved by spinning the impellers. There’s a whole stack of about twenty of these in the pump. I’ve shown two stacked together on the right hand side in the front.

Each of these is comprised of a stainless-steel cup, a plastic rotor, and a grey plastic cover. Water is the only lubricant for the pump, so it’s important that the impellers are sealed in the pump with just the right amount of pressure. Too little and they’ll spin without pumping. Too much and they’ll lock up tight.

Pump Impeller Details
Pump Impeller Details

Nifty engineering. Not cheap, of course, but ¾-horsepower turns out to be a lot more motor than we need so it wasn’t as bad as it could have been. (Why there was an almost certainly used, 1979-vintage, oversized pump in the bottom of our well is something I can only speculate about. But I’m sure it has something to do with the fact that the guy who built the house had a father who was a plumber.)

Put the whole thing back together, sink the pump back down to the bottom of the wellWhy is the pump on the bottom? It’s a good, basic physic question. Think atmospheric pressure., let the water run for a few minutes to clear out the rust and grit stirred up by the process and all is well, no pun intended.

Until the water stops flowing again (at about ten o’clock last night). I’ll take pictures this time.

(Update: it was just the switch on the tank in the basement, so no new pictures.)