Export thread

People.

Have a shallow well pump, Craftsman 3/4 HP. Tested it with 120v first to make sure it actually runs. Then connected it all up with pvc pipes, and electrical 240V. I switched the button to 240V internally first. I have voltage at the pressue switch but the pump will not even start. I primed it with water as well. No luck. Could it be a bad pressure switch? Can one do anything else?

Thanks.

Time to get out the DVMM and start testing the electrical connections. The might be at the pump mode switch itself.

Just be thankful it wasn't a submersible pump that you didn't verify the 240V operation before installing. I just pulled my pump because the electrical connection broke down near the pump in the well. Had to make a tool to unmount the pit less connector and it was stuck so tight it took a engine crane to free it. Pulling a 100 ft of hose with water and pump is exhausting for a 62 yr old to do by himself.

StarTech said:

Time to get out the DVMM and start testing the electrical connections. The might be at the pump mode switch itself.

Just be thankful it wasn't a submersible pump that you didn't verify the 240V operation before installing. I just pulled my pump because the electrical connection broke down near the pump in the well. Had to make a tool to unmount the pit less connector and it was stuck so tight it took a engine crane to free it. Pulling a 100 ft of hose with water and pump is exhausting for a 62 yr old to do by himself.

Click to expand...

Well, I got 240V at the 2 wires from the source (taken at the 2 "buttons" on the pressure switch), but not at the 2 other screws/contacts at the switch. But the contacts are "touching" meaning, the switch 4 contacts are touching the contact points on the switch . What is the mystery? Shouldn't my pump fire up? Why is not the 240V being transferred to the other 2 contacts?

noquacks said:

Well, I got 240V at the 2 wires from the source (taken at the 2 "buttons" on the pressure switch), but not at the 2 other screws/contacts at the switch. But the contacts are "touching" meaning, the switch 4 contacts are touching the contact points on the switch . What is the mystery? Shouldn't my pump fire up? Why is not the 240V being transferred to the other 2 contacts?

Click to expand...

Can you send a pic of the connections at the pressure switch?

StarTech said:

Had to make a tool to unmount the pit less connector and it was stuck so tight it took a engine crane to free it. Pulling a 100 ft of hose with water and pump is exhausting for a 62 yr old to do by himself.

Click to expand...

I have 2 wells. One for the house and one for the heat pump. 120' deep and we have the slimy bacterial iron. I have had to pull pumps quite a few times in the last 25 years. Last time was a year ago. At 65 pulling up the slimy mess whipped me pretty good. I feel your pain.

Hammermechanicman said:

Can you send a pic of the connections at the pressure switch?

Click to expand...

This is insane- I just measured ohms and V and got continuity on all 4 contacts on the switch. ALSO, now, I am getting 240V on the 4 contacts!! So, I figured, let me take V on the 2 leads going INTO the motor itself, I opened up the back and touched the 2 hot leads at the motor itself and they registered 240v! How can I get 240V at the motor itself and still the motor will not start?

Going to assume it is a split phase capacitor start motor. Even if the start winding or capacitor is bad you should still get a good humm out of the run winding. Does it have a capacitor?

Hammermechanicman said:

Going to assume it is a split phase capacitor start motor. Even if the start winding or capacitor is bad you should still get a good humm out of the run winding. Does it have a capacitor?

Click to expand...

Yes, it has a capacitor. It is a Craftsman, Model # 390.261B, the B may be an 8, hard to read. 3/4 HP. Can I run this on 120V? The switch can be switched to the 120V side. Then I use only one wire, and cap off the other? Think that would help? I dont care what V it runs on, I hardly use it. Maybe the 240V switch position is bad, if so, the 120V side could do the trick(?).

remember- in post #1, it ran on 120V before I connected it all up.......

I am not exactly sure what you have. I am going to assume the pump uses an external pressure switch. On the pump itself should be a tag, plate or sticker that has the motor info like voltage, amp draw, Hz and maybe some other stuff. SOME pump motors can be dual voltage 120/240 but it requires some rewiring the connections. There will usually be a schematic for this on the cover for the motor connections. If you tested it on 120v but then connected it up to 240v i am confused. What does the plate on the pump say the voltage should be?

Certainly you can try to run the pump on 120vac. There should be a diagram indicating how to wire power when set to the 120vac setting. Likely you will have line & load & a ground. Connect that way, switch the selector to 120vac and it should work.
It could be there is a fault in the motor where one leg of the 240 has a break, either a broken wire or loose connection. Give it 120, and it doesn't use that conductor, so it works. Try the 240 and you are applying two 'hot' leads, and apparently the switch is sending power... but it doesn't run. Likely one leg has taken a hike. (get it)
tom

tomw0 said:

Certainly you can try to run the pump on 120vac. There should be a diagram indicating how to wire power when set to the 120vac setting. Likely you will have line & load & a ground. Connect that way, switch the selector to 120vac and it should work.
It could be there is a fault in the motor where one leg of the 240 has a break, either a broken wire or loose connection. Give it 120, and it doesn't use that conductor, so it works. Try the 240 and you are applying two 'hot' leads, and apparently the switch is sending power... but it doesn't run. Likely one leg has taken a hike. (get it)
tom

Click to expand...

OK, so if one just switches the selector it may require more work like rewiring? That may be my problem. I made no other wiring changes assuming the switch was all that needed to be done. I never knew. I should look at/study the diagram on the label. Feedback appreciated.

Sounds like bad pressure switch, 120 would work fine but install a new pressure switch anyway.

Some jet pumps will have a knob switch on the box on the motor where the wires go in to switch voltage but most require changing a couple wires around. If this pump uses an external 4 contact pressure switch it can not change the voltage the pump needs. If the pump is dual voltage then somewhere on it there should be something that tells you how to switch the voltage. At this point we are just guessing. If it ran properly with 120v and then you applied 240v to the same wires i would be suprised that the magic smoke didn't come out.

tomw0 said:

Certainly you can try to run the pump on 120vac. There should be a diagram indicating how to wire power when set to the 120vac setting. Likely you will have line & load & a ground. Connect that way, switch the selector to 120vac and it should work.
It could be there is a fault in the motor where one leg of the 240 has a break, either a broken wire or loose connection. Give it 120, and it doesn't use that conductor, so it works. Try the 240 and you are applying two 'hot' leads, and apparently the switch is sending power... but it doesn't run. Likely one leg has taken a hike. (get it)
tom

Click to expand...

Tom, I like your response. I was thinking someone would remind us the 120/240 switch doesn't convert the pump; it lends a crutch so the pump wont try to run on one leg.

kjonxx said:

Sounds like bad pressure switch, 120 would work fine but install a new pressure switch anyway.

Click to expand...

So, 240V at the pump itself (bypassing the pressure switch) condemns the pressure switch???

noquacks said:

So, 240V at the pump itself (bypassing the pressure switch) condemns the pressure switch???

Click to expand...

Not necessarily. Generally the switch will break one leg(crutches not needed...) not both. When switching the 120V, breaking that hot will stop the pump. Breaking the same hot lead will also stop the pump when set to 240v mode. Takes two hots for 240, and only one for 120V operation. For that reason, it is likely the pressure switch only makes/breaks one of the two leads to the pump motor.

tomw0 said:

Certainly you can try to run the pump on 120vac. There should be a diagram indicating how to wire power when set to the 120vac setting. Likely you will have line & load & a ground. Connect that way, switch the selector to 120vac and it should work.
It could be there is a fault in the motor where one leg of the 240 has a break, either a broken wire or loose connection. Give it 120, and it doesn't use that conductor, so it works. Try the 240 and you are applying two 'hot' leads, and apparently the switch is sending power... but it doesn't run. Likely one leg has taken a hike. (get it)
tom

Click to expand...

It just hit me- I was looking at the end/rear of the pump wiring and the green ground wire has no connection to anywhere. Could that be the problem? Should I connect a wire to that and ground it where the power source is at the pressure switch, together with the source ground?

In all cases I know of, the ground connection is not used in normal operation. It is to be the alternate path for juice to take vs going thru a person. The two used in AC current are the Line and the Load. Black & white.
In 240VAC, there are TWO conductors, out of phase with each other so the difference between them is double each conmductor to ground.
Have you found 120VAC settings? Is there anything indicating how to wire for 120VAC? Ground is ground is ground... or SHOULD BE.
Take some pics of things & post.
tom

Crazy- I tried to upload just one picture of the back of the motor like Tom suggested and I get from this website "the uploaded file is too large for the server to process". Sheeeesh.

tomw0 said:

In all cases I know of, the ground connection is not used in normal operation. It is to be the alternate path for juice to take vs going thru a person. The two used in AC current are the Line and the Load. Black & white.
In 240VAC, there are TWO conductors, out of phase with each other so the difference between them is double each conmductor to ground.
Have you found 120VAC settings? Is there anything indicating how to wire for 120VAC? Ground is ground is ground... or SHOULD BE.
Take some pics of things & post.
tom

Click to expand...

Tom,

When you say "120VAC settings", you mean the simple hex switch to switch back/forth from 120 and 240?

noquacks said:

Crazy- I tried to upload just one picture of the back of the motor like Tom suggested and I get from this website "the uploaded file is too large for the server to process". Sheeeesh.

Tom,

When you say "120VAC settings", you mean the simple hex switch to switch back/forth from 120 and 240?

Click to expand...

open your photos in a phot editing app
Resize the photo to 12" on the longest side & set the resolution to 72 dpi and SAVE it as a JPG
The WWW see RAW f ormat phone images as 5 times the size thatthey are .

Open PAINT program. Open the picture file. Find the 'reduce' image thingy near the top left. Reduce by 50% in both directions H&V. Click "FILE" and then 'save as' and select JPG. Name it something you can remember. Try uploading that. PAINT can make it smaller, but still legible.


I can't explain as i DO NO know what you have in front of you.
I AM NOT AN ELECTRICIAN.
Search for the installation DOC for the pump if you have a Model/Serial etc.
tom

got it, here:

tomw0 said:

Open PAINT program. Open the picture file. Find the 'reduce' image thingy near the top left. Reduce by 50% in both directions H&V. Click "FILE" and then 'save as' and select JPG. Name it something you can remember. Try uploading that. PAINT can make it smaller, but still legible.


I can't explain as i DO NO know what you have in front of you.
I AM NOT AN ELECTRICIAN.
Search for the installation DOC for the pump if you have a Model/Serial etc.
tom

Click to expand...

Model is Craftsman, 390-2518. SN is not readable anymore. Never requested/demanded that one here must be an electrician. Help offered though is most appreciated, whatever your capabilities are. If you cant help, then thats OK. I was able to post a pic. Not sure if that helps, people. I have no where else to ask for help. Thanks.

Looks like the black knob sets the voltage the pump is looking for. The pressure switch is a dual pole switch. Do you have 220-240 at the terminals of the pressure switch of the wires from the service panel? Is the black switch set to 230? Do you have 220-240 volts at the terminals of the pressure switch of the wires going to the pump?
From the picture the pressure switch looks pretty crusty. Might want to just replace it.

The disclaimer I AM NOT AN ELECTRICIAN was to make you aware that I am just a guy who has done some stuff, but am not qualified to give electrical advice.

This link is to the owners manual, including INSTRUCTIONS TO SWITCH TO 115V and parts.


Hope this is helpful.
tom

Hammermechanicman said:

Looks like the black knob sets the voltage the pump is looking for. The pressure switch is a dual pole switch. Do you have 220-240 at the terminals of the pressure switch of the wires from the service panel? Is the black switch set to 230? Do you have 220-240 volts at the terminals of the pressure switch of the wires going to the pump?
From the picture the pressure switch looks pretty crusty. Might want to just replace it.

Click to expand...

I have 240V at the terminals at the PS. Yes, the black hex shaped switch is at 240V. But no V at the PS terminals. So wierd. Gotta be a bad PS, right?

BUT, just now, I tried something- I disconnected the 2 wire leads coming from the back of the pump from the PS, and connected them directly to a cord, going to a 120V outlet, and BAM, pump runs. So, it runs on 120V but not on 240 even when the hex switch is turned to the 240V selection. I dont care if it runs on 120 and not 240, as long as it runs.

tomw0 said:

The disclaimer I AM NOT AN ELECTRICIAN was to make you aware that I am just a guy who has done some stuff, but am not qualified to give electrical advice.

This link is to the owners manual, including INSTRUCTIONS TO SWITCH TO 115V and parts.

Craftsman 3902518 water pump manual

Download the manual for model Craftsman 3902518 water pump. Sears Parts Direct has parts, manuals & part diagrams for all types of repair projects to help you fix your water pump!

www.searspartsdirect.com

Hope this is helpful.
tom

Click to expand...

Wow, so helpful, Tom. Thanks. I should study that! I will let yous know what happens, if I can glean anything from that manual........

I got it running!!!!!! Yahoooo! Finally. On 240V. I dont know what I did differently, but it works. I primed it with a garden hose, and it pumps great. BUT, it doesnt shut off unless I cut the power to it. Now that I (we) got this far, what do I do to the pressure switch to naike it shut off? I will read up more on that diagram meanwhile.

Thanks, people.

If it is a bad PS can I install a new one I have , the range for which is 30-50 psi? I cant tell from the manual Tom posted what psi's the pump is rated for. All I can find is on page 2, showing "discharge pressure " of 40 psi. Would my 30-50 work?

You might just try loosening the PS adjustment screw. They are mostly spring loaded switched with an adjuster to change the open/close pressure. If adjusted too high(by someone trying to get it to run) it would not shut off no matter the pressure. If you look at the PS I expect(do not know) that you will see a spring with a threaded shaft sticking out of it. The shaft is attached at the base, and it has a 'plate' that rides on the shaft and compresses the spring. If the spring is compressed too tight, the switch will not operate. Too loose and it will not turn on. Generally you tighten the screw (CW or CCW) to make the plate/washer/?? push down on the spring harder for higher pressure, loosen to make the spring push less.
All PS have a range. Yours is likely close enough. IMO. BTW, not a plumber either.
tom

tomw0 said:

You might just try loosening the PS adjustment screw. They are mostly spring loaded switched with an adjuster to change the open/close pressure. If adjusted too high(by someone trying to get it to run) it would not shut off no matter the pressure. If you look at the PS I expect(do not know) that you will see a spring with a threaded shaft sticking out of it. The shaft is attached at the base, and it has a 'plate' that rides on the shaft and compresses the spring. If the spring is compressed too tight, the switch will not operate. Too loose and it will not turn on. Generally you tighten the screw (CW or CCW) to make the plate/washer/?? push down on the spring harder for higher pressure, loosen to make the spring push less.
All PS have a range. Yours is likely close enough. IMO. BTW, not a plumber either.
tom

Click to expand...

Thanks, Tom. I peeked around a bit more before I started messing with the speings like you said, and i decided to take apart the 2 nipples on the to/from the narrow pressure black tube that feeds the PS. They both were clogged! Geez, no wonder. I ran a fine steel wire through both of them, and opened up.freed up the orifices. They were packed with gunk! Put it all together and now the pump stops! Success in steps!

Lastly, I found that the pump starts/stops within a second or 2, with a tiny leak in the pipes. I fixed the leaks, and now pump behaves a bit better. But shouldnt I have installed on top of this pump one of those low pressure air tanks, in case of a slow tiny leak, the pump wont kick on unless the pressure in the tank is depleted say, over a much longer time? Like this one:


The old pump I removed (30 years old or so) had one. After this, I am completely done! Thanks.

Yes you need a tank. Size depending on your application. Modern tanks have a bladder in them to separate the water and air. In older nonbladder tanks the air would slowly be absorbed and air would need to be added to the tank every couple of months. Most systems are 20/40 or 30/50. If you get a tank you should get fairly detailed instructions how to set the bladder pressure of the tank for your system and you will need to install a pressure gauge to know what is happening . The hardest thing for a pump to do is start up under a head of pressure. You want it to have a few startups as possible. That means proper size tank, the bigger the better, setup properly and pressure switch setup properly. A fast cycling pump is not a good thing.

Yup, save $$ and save the pump by adding a pressure tank. Longer run time on each cycle with ~no loss of head pressure cuts the surge electrical current flow number and lets the pump do a run cycle before shutting down. As stated, the bigger the better with more noticeable effect if your water use is high, such a multiple users vs a small household.
And, read the directions. The tank can be 'teed' in just about anywhere in the line and work fine.
tom

Wow, too much- I unscrewed the old tank from the old pump, tank is still good, almost new. Added a little pressure to 20 lbs (stated on sticker), screwed it onto the top of the pump thread, turned on the power, and pump runs, then stops, and stays off! Tested pump by turning on the hose faucet 30 feet away, pump runs great, no other problems!

You guys are great! Thanks.

When you turn on the hose faucet, the pump should not run until the pressure stored in the pressure tank is exhausted. The compressed air in the tank will force water into the system to feed the hose. As I sort of understand, you want the pump to kick on just before the air pressure reaches your setting. Thus as the air pressure is used up, the pump should kick in just before. The pump will then run, even with the hose faucet closed, and compress the air until hi shutoff is reached.
tom