sump pump float switch failure seeking advise from communty

[mark gordon]

hello all,  

before I spend more money I was hoping to get a bit of feedback from the community 

i have a greenhouse with the IBC chop system, been growing for about three years and have found many useful tidbits here.

 my system uses a large 60 gallon trash can for a sump, buried in the lowest part of my greenhouse, all grow beds drain into a common drain pipe which feeds into the trashcan.  I have a Harbor freight waste sump pump on a float switch in bottom of the trashcan,  It runs about 2600 gph,  for about 30 seconds every time the float switch is activated, which is then fed back up 6ft to the fish tank, and I siphon off about 6-8 gallons through a small 1/2"T fitting on the main pipe to feed my grow towers. 

Everything has been running for about three years, then over the last week my pump has started to fail.  

I just expanded ....added two new 30 gallon grow beds, and about 50 gallons more water into the system, plus added some grow towers.  No water leaks, system has rebounded nicely and  strawberries are now vertical and producing berries.

Problem is the pump has been cycling on way to often, and not pumping all the water down to the bottom.  as near as I can tell, the float switch is randomly coming on and shutting off early. causing the water to only cycle a small amount at a time, which is speeding up the flow rate on the system and everything is draining more often than desired, and my power bill is increasing.

 last week I pulled out the pump, took it apart and pulled out a good amount of clay pellets that had been sucked in.  Now have a collection net on outflow of main drain pipe, and small screen wrapped around bottom of pump.  now float switch is failing.  

Should I replace the whole pump? or can anyone recommend a better float switch to add.  The pump when it cycles on is still rock solid, and it is relatively easy to service,  Just not sure what type of switch replacement I should be getting.  the float is only about twenty inches long.  Looks like Monday will be pump repair day.

any advice appreciated

[Philippe Pauvert]

Hi Mark, an electric pump is aging when it starts, better said the motor. If you experience the first problem after 3 years it's not so bad. So try to spare the pump startups.

As for the float. Looks like the contacts are wasted, might be because the float is rated near or below the pump power. eg 10A for 15A...

I use the float to pilot a relay that actuates the pump. Electrician name that a contactor or whatever. I started to use them with the timers and other automations and now they are always in the circuit.

[mark gordon]

Anybody else want to add anything?  Can anyone recommend a solid replacement float switch I can swap out with my wasted one.  I plan on reuseing the pump until it dies,  The whole purpose of the forum is for an exhange of ideas and info.  

thanks for the quick response Philippe,

 I am going to check with our local Harbor freight outlet and see if I bought an extended warranty, who knows maybe they"ll give me a break on a new one.  Anyway the pump is coming out tomorrow evening, and the system will be idling for at least one day.  

[Vlad Jovanovic]

Hi Mark,

Any 'ol halfway decent float switch should do (110v)...

https://www.google.com/webhp?sourceid=chrome-instant&ion=1&...

Whether or not they use a mercury ball to make the contact and close the circuit or not, most of them operate in a similar fashion. Your "biggest question" in terms of "operational decision making" is whether your current float switch electrical plug is "piggybacked" onto your sump pumps, or has to be hardwired...

You may (or may not) want to stay away from the mercury ball float switch design (especially if your buying crappy Harbor Freight 'junk')...mercury introduced into an AP system via a faulty cheap float switch would suck...

But otherwise, there is nothing all that special about any number of liquid level switches that operate a pump (closes a circuit and turns a pump on, opens the circuit and turns the pump off) are all that "special". Keep the pump, just swap out the switch that operates the pump 

[mark gordon]

Thanks Vlad,  I have been looking at alternative pumps to move into as time allows; I took the old pump back yesterday, and it was still under warranty so I took home a brand new one, and 

I do realize the pump from "harbor" is often considered "Junk".  But looked at from a hobbyist perspective.  When I first got started in the aquaponic garden building phase - I had know idea how much of a change this would create in our lives, and the lower price point was very attractive.  So I found the biggest all steel pump that would be easy to service.  and just got growing.

 Now this gardening has become a daily part of my  lifestyle, and as we expand, we will be upgrading to better equipment.  

thanks for your input, your online discussions are very helpful 

[Jeff S]

Big box stores have float switches for under$20.

[Adam McMillin]

you got a sump pump from harbor freight to last 3 years!?!  I cant get a pump to last reliably for a year just in my basement.  I would say you got a bargain.

[Jack Rife]

Switch to smaller pump and run constantly, eliminate float switch, even commercial applications, float switches constantly cause problems. I use a 600 gph pump from Harbour Freight $42.00, pluged it in 4 yrs ago still going strong 24/7 700 gal total system GB and DWC. Swirl filter prevents waste build up in the sump tank.