Friday, September 3

Pump woes

This morning a little after 7 the pump doctors arrived to see what could be done for the patient. Our well pump was not producing what it should, so it was pulled. It’s a Grundfos pump, supposedly top-of-the-line stuff according to a ranch guest who happened to be the CEO of the American manufacturer in Clovis, California (their main plant is in Denmark). After talking with him over a several-day period I was convinced that we would get a nice long life from a Grundfos. It lasted a little over five years before giving up the ghost.

The two workers pulled out 23 20-foot lengths of pipe to get to the pump, then added five more pieces and a new non-Grundfos pump and stuck everything back down the hole. This time a sand filter about four feet long was added. It seems there is a lot of gritty sand near the top of the well that drifts down and was probably what wore out the pump to start with. The whole operation took about six hours.

Some stats: The depth of the well is just shy of 1,000 feet.
The static water level is at 326 feet.
The new pump is at 560 feet.
The bill for all this will knock me off my feet.

More stats: Our old pump drew 1,700 watts. The new one uses 2,700 watts. The wire size down the well had to jump from #10 to #8 (fatter). We’re going to need more solar panels! Or pay PG&E, the local utility, $104,800 to run power up to our house.

I think we’ll stick with solar power.


Pete S. said...

Why was the well drilled to 1000 feet if the pump only needs to be at 560 feet?

Why did replace the old pump with a more powerful one?

Is the Grundfos blameless for the early failure, given that it was affected by sand?

Tom Hurley said...

Significant water flow was found at the 1,000 foot depth. It comes in and rises in the well. Shallower than that there was not much water.

Since the static level was now at 326 feet instead of the roughly 150 foot level when the well was new, the pump had to be lowered so it wouldn't run dry as the level in the well dropped due to being pumped. Thus the need for more power.

Grundfos prides itself in handling sand. The CEO told me they had sand samples from wells all over the world to use for testing. Oddly, we don't get much sand in the water coming from the well, so I don't know what caused the failure.