Baldor/Armstrong#3

[burner1941]

Just got called that Baldor motor #3 is overloading with the slightess load. The old repaired one operates just fine on the test.

Officially this has been going on since July 11th. [from my point of view since June] Obviously Baldor didn't check it, like the repair shop requested.

Baldor was contacted by the repair shop, and told we had to do something, heat is needed now. Baldor agreed to allow repair shop to obtain another brand motor, and they will make it right with them.

Apparently Baldor has a bad batch of motors. It's hard for me to accept, because of the amount of time that has elapsed.

I do think Baldor is a fine company, and has quality products, but then it shows that they have weaknesses. Their lack of communications and having to call back to get them to act, is dissapointing. Of course I'm dealing thru the repair shop, but they have a stering reputation here in town, so I'm thinging it's Baldor that's lacking, in this situation.

I'll update when I know something new.

Burner

[Oscar_Lives]

Try Reliance. They are world-class.

Emerson/Fasco are shit.

[Jake]

Of course I'm dealing thru the repair shop, but they have a stering reputation here in town, so I'm thinging it's Baldor that's lacking, in this situation.

I'll update when I know something new.

Burner

Burner, the shop is screwing you around... Not Baldor.

You have another problem here... I'd bet you money on it. I've never seen 1 bad Baldor motor come from the factory... in 20 plus years.. much less three.

Check the system out more... something is wrong. Simple stuff.. is the rotation right?

BTW, Baldor is offering to buy another manufacturers motor because they're tired of screwing with your motor shop and want done with it. They tried to do the right thing....

Osc... Reliance Motors are excellent... and pricey for General Duty. I do install them in the most severe applications.

A pump, running right, can be powered by a Leeson or Marathon or even the Chinese junk just as well as a Baldor. The only question then is how long it will last.

Jake

[burner1941]

I don't think so, talking to the repair shop since last post I found out that Baldor is going to do is give them a good motor of their own. The repair shop is working it out with Armstrong Pump to provide another motor. Armstrong distributor in Columbus, Ohio is aware of the situation, so if the repair shop is blowing smoke, they are in concert together.

I'm not paying for anything this is warranty work from Armstrong Pump Co. provided by their authorized repair shop. So I can't really dictate what they are going to provide. This is on Armstrong. The only thing I'm paying for is the repair of the old Armstrong pump.

Burner

[burner1941]

Jake, didn't answer some of your questions.

The rotation was checked several times, volts, amps. I've been challenged by different people.

I'm just service not an engineer, however if something changed in the system to change the load on this pump, it will show up when I reinstall the old original pump, because I'm chicken shit to wait any longer.

I "think" I know this much, when you shut off a discharge valve on a centrifugal pump, and the motor amps are below full load, and then barely crack it open and the amps go crazy, it's hard to believe that it's the system. I've had a similiar problem before and it was a solved by a larger horsepower motor for the system. It could have been sized wrong, and operating on the end of it's curve. With this job, it has a 12 or more year history of the same pump, with the balancing valve open much further. The old pump's motor didn't fail, just the bearings, and it needed a seal plate.

This pump is on a primary loop in a boiler room, with two boilers and their pumps pumping thru the loop, and the secondary pumps are also pumping thru this loop. I've had the other pumps off/on and the results are the same. The primary loop probably isn;'t 50 feet around the boiler room. So I think it's the pump/motor.

Crazy thing about this job, is they have two boiler, with their pumps, and two secondary pumps, only run one at a time. However they only put one primary pump on the system, if it's down your done. Go figure.

Like I said we'll see.

Burner

[Jake]

burner1941 wrote: > I "think" I know this much, when you shut off a discharge valve on a

In my experience, that's correct. No discharge FLOW will idle down the pump.

When flow exceeds the prime mover's (motor) ability to handle it... the motor overloads trying.

Can the impeller clearance to the volute be adjusted on these pumps? Impeller design or differences will change flow... as you checked for... but so will the clearance between the impeller and the volute.

I would assume there is a mixer valve in the system? Is it OK? Does your primary loop maintain its setpoint (like 180 or whatever)? If it's fluctuating much... that would indicate a valving problem to me.

Higher than spec. flow also means poor transfer... which translates into really bad efficiency. Do you know where the flow is now?

Sorry for all the questions... it's just I've seen many, many times where something like a pump is blamed for trouble when it is really buried a little further along...

Granted... that's all in commercial/industrial systems... but they only make hydronics more interesting... don' they (-;....

Jake

[AKS]

That is normal for any pump for amperage to go down if flow came to complete shut off, not only the amperage goes down but in addition RPM will increase, however these ONLY happens on none positive displacement pumps. Note on positive displacement pumps regadles if is liquid or gas it is just the opposite, the amperage will continue to go up until something gives up fusses, circuit barker, overload, motor itself Etc. Dido

[burner1941]

This weekend, I installed the repaired original Armstrong pump, no problems worked like always. So in my opinion it's official the Baldor motor is defective.

Talking to the repair shop, they told me the owner was the one who is trying to get this resolved. So he's purchasing a motor and will settle up with Baldor. Baldor really aren't doing anything different just standing behind their product. As far as I'm concerned they struck out on performance on this one. But then again no one is perfect.

Burner

[Steve Scott]

[burner1941]

Your sequence is correct.

The only correction to your comment, is that I DID NOT replace motor, this new pump hasn't left the repair shop, since officially July 11th. I believe the repair shop. They said the eternal part were the same, with both pump. This makes since to me since their the same model number. [I realize changes could have been made] The 3rd motor from Baldor draws full load amps on the bench, so they didn't bother to hook it up. Baldor said this third motor was from a different batch.

I can't 100% say it's the motor, but I'd be willing to bet, it is. Baldor eventually said the first two motors were bad, and sent the third. The repair shop said the third motor is bad, I believe. This work is being performed for Armstrong and Baldor, not me. Of course I'm taking it in the ass on this job.

Burner

[Bob_Loblaw]

"AKS" wrote

circuit barkers?...fusses?? ya, if I was looking for HVAC advice from a complete stranger, I'd listen to you.....ROTFLMAO!!!!!

[Jake]

A centrifugal pump is not positive displacement...

It's also common practice... as a matter of fact code in most locales... to make certain there are pressure relief valves on real positive displacement pumps.. whether they be lobe, progressive cavity, rotary gearpump, piston, screw, diaphragm, etc.

Under NO circumstances (except maybe super critical systems) should a pump stall or overload. A external or internal relief will keep system pressure below the safeties.

Jake

[Jake]

bother to hook

Curious about this. The motor drew near FLA on the bench without a mechanical load of any kind connected... or was it hooked to a pump?

Jake

[-zero]

You really need to add a couple of gauges (1 on the inlet, and 1 on the outlet flange) and record the system-off pressure and the system-on differential pressure. Then the quasi-system curve can cross against the pump curve to see what may be happening. If you have any valve movements (3-way, etc. vs. on-off control), you need to log those also in there respecting positions.

If you post the pump info and the readings, I'm willing to have a look see.

-zero

[AKS]

NO ONE IS ASKING YOU TO do so JACKASS!