Capacitor on pump control went bloohey

[OkeeDon]

I recently had a 4" well drilled on my Okeechobee land, along with a 1 HP submerged pump. I have it hooked to Hudson float valve in my pond in order to keep the pond at a constant water level. It flows about 25 gallons/minute. After 3 days of constant running to get the pond full, it settled down to an hour or two every other day or so to keep it full. It hasn't been used for anything else.

Power is supplied by a 20A, 240V breaker in a subpanel, which in turn is supplied by a 30A, 240V breaker in a garage about 150' away. Wire size is 10-2 w/ground NLM, buried 24" deep in a trench. My water contractor said that the 20A breaker was sufficient for the 1 HP pump. The breaker is connected to the pressure switch, which in turn is connected to a Franklin control box.

My son-in-law called and told me the pump wasn't running. I ran out there today to check it out. All of the breakers were on, and the pressure switch contacts were in the closed position, but the pump wasn't running. I verified that it had power as far as the pressure switch, then I opened the control box.

What greeted me was a gooey, gloppy mess that leaked out of the capacitor. I cleaned out the glop, took that part of the control box to the water contractor, and he simply handed me a new one. I slipped that on, and everything came back on and worked just like new.

I don't have any idea what could have caused it, and neither does the contractor. It could have simply been a defective capacitor, or it could have been caused by something in the pump or the wiring. We were guessing at things like a power surge, a lightening strike (although there has been little rain and no thunderstorms of which I'm aware), etc.

Our plan is simple -- we're just going to wait and see if it was a one-time thing, in which case it was probably a defective capacitor, or whether it happens again, in which case we'll investigate further.

But, I'm curious. Does anyone know anything about these things, and have any idea of what happened?

 

[_RaT_]

Don, the start capacitor is typically what goes. I have replaced them on well pumps and heat pumps. A simple $2 part is responsible for a lot. Capacitors seem to have a higher failure rate then most other electrical componets. They are typically wet capacitors. It is a fine line between 100% good and 100% bad. I would venture to say you had the latter and it did what they do, rupture. I suspect your going to be OK.

 

[cperky]

I agree with RaT about the life of a capacitor. It is not uncommon for capacitors to go bad. The usually swell and leak when they go bad. The only thing I have found that helps the lifespan is to reduce the amount of heat that is around the capacitor. If it is in an enclosed case make sure that there are some air vents so that you can get airflow across the capacitor.

 

[Junkman]

Don, I regret to say that I know a lot about them. I had a 2 HP 220 volt, single phase submersible pump on my well and have experienced this many times at my old home. It is a result of a lightning strike somewhere along the aquifer that your well is drawing its water from. This sudden surge of "power" will blow out the capacitor and the only remedy is to have spares on hand. At my old home, this would happen a couple of times a year and sometimes, it would actually blow out the pump also. The good news is that it is covered by your homeowners policy if you loose a pump as a result of lightning, or at least if you are in CT. I have a spare relay and also a spare thermistor, but have never had to replace that one. At my new home, I have a surge and lightning arrestor on the electrical panel, and have not had a problem but twice in 20 years, and never since putting on the arrestor. I remember reading about a kid that was playing ball in Florida that was killed by lightning because of a storm that was far away. They later installed some high tech device that would give early warning when the ground wasn't safe to play on because of this tragedy. I don't remember all the details, but I think that it was a Little League game.
Here is an interesting article on lightning and its effects..... web page

As a side note, one of my Weimeraner's name was Lightning!!!!! /forums/images/graemlins/smile.gif

 

[chucko]

Don I have had to replace a few. (maybe 3 in 15 years) were I am at. I think the heat here in fl gets to them also because every one that I replaced was in June or July. I keep an extra one.
But yours should not have been from heat this time of year.
Does anyone know if cycling the pump on and off affect them. I was told one that that it did and I bet Don's did that a lot filling a pond

 

[_RaT_]

Cycling should not be a factor since it would be almost impossible to cycle it that quickly to cause a capacitor to go bad. It could very well just have been a weak capacitor to start, developed a short and being in a sealed container, heated as a result and burst open. When little we used to blow capacitors up by attaching them to a extension cord and plugging it into 120V.

 

[accordionman]

DON,
even though you are running with no. 10 wire, you have a
run of 150 feet. there may be enough voltage drop to make
a difference. i suggest you check the voltage at the pump,
if this is possible, when it is running. if the drop is more than
10%, this could be the cause of your capacitor failure. then
you would need a larger wire size. ouch! i would keep a supply
of these on hand, in case it happens again. these capacitors
can be bought for just a few dollars.
good luck with your projects.
accordionman
william l. brown
wright city, mo.

 

[OkeeDon]

Good suggestion. I was concerned about that, but stayed with #10 wire to hold the costs down. Going to a bigger wire size, or living with a slight drop for a while, isn't really a problem. You see, I'm cheating. This wiring run is temporary, coming from my son-in-law's garage next door, until we can get our own power. I can get a temporary meter as soon as I pull building permits, but have to pay for it. My plan is to use the power from my daughter's place, along with my generators if needed for construction, until we get our Certificate of Occupancy and can get a permanent meter.

It's a trade-off -- later, I'll be tossing this temporary setup, but I'll save by not paying for the temporary hookup from the power company, and I can use my well in the meantime.

My kids have two meters -- one for the house and one for the garage, and I'm coming directly off the breaker box for the garage, which we just had installed, so I'm not over-taxing their power. I'm just giving them the $$$ for their second power bill until I unhook, so it's a win-win for both of us. Later, my s-i-l plans to do some extensive outdoor lighting, etc., from this meter. When we had the meter installed on the garage, I had the electrician install a 50A breaker for my tig welder and a 30A 120V breaker for my motor home, so I'll be using most of the juice, anyway. It's handy to be next door to family.

 

[_RaT_]

Don, what is the operating current of the pump at 240V. Being 240V and only 150 feet away, I think you will be within voltage drop maximum.

 

[OkeeDon]

I guess you're asking about the amperage; I don't know. I never saw the pump before it went into the well casing, don't even know what brand it is. It's 1 HP @ 240V single phase; my water contractor said to install a 20A , 240V breaker and I did, in the subpanel about 5' from the well. I wanted to be sure I had enough current (as long as the wire could handle it), so I installed a 30A, 240V breaker in the main panel, 150' away. The tables I looked at, at the time, said the #10 wire could handle the current at that distance, although there wasn't much margin. I would have had a greater margin with #8 wire, but there was a pretty good price jump between #10 and #8. If the installation had been permanent, I would have gone with #8, just to have the extra margin.