Ejector-Head- Incredible Product Defect......

[xylstra]

Ejector-Head for Jet-Lift Deep-Well Pump - Wrong Connector Pipe
"The Connector-Pipe's the wrong length @##%$**!!!"
.... Can anyone relate to this? (I want to hear your story)......


The attachments below illustrate a (brand-new, fresh out-of-the-box!) 'TAIFU' (Chinese brand) ejector-head in the attempt to assemble it. The first photo pretty much says it all: the venturi discharge-end projects 18mm above the end of the connector-pipe. The second photo shows what happens next: the standard fitting will only engage barely 3 threads before bottoming-out on the end of the projecting venturi, i.e. it is physically impossible to do it up properly (note the amount of exposed thread). Any attempt to force it will only crush the venturi and risk damaging it. The third photo is staged to show how it should appear if properly tightened.
The measured length of the supplied connector-pipe is 161mm and by my calculations, should in fact be 178mm.
Although in my case the brand is 'TAIFU' I wouldn't be surprised if this ejector-head is a generic type supplied with a variety of other Chinese-origin brands.
I am interested to hear if anyone else has encountered the same problem and whether your story ultimately lead to any resolution with your supplier e.g. warranty claim due to deffective goods, etc.
I suspect that my case is only the tip of a very large ice-berg and I want to gauge the magnitude of the problem. I do expect however that there may be a lot of engineering-illiterate idiots who have foolishly installed this in their well not appreciating that the connector-pipe is not done-up properly i.e. in service; leaking/loss-of-prime, risk of joint separation, premature corrosion of threads.
Looking forward to your replies.

 

[Valveman]

Threaded PVC or steel pipe would work. It is your barb fitting that is the problem. People installing this on PVC or steel would not see this as a problem. Use a regular threaded coupling and a short metal nipple over the venturi, and attach your barb fitting to the extra nipple.

 

[xylstra]

Hi 'Valveman'. Thanks for the reply. I need to clarify that I already know all the solutions and work-arounds (I am an engineer). Seeking solutions was not the purpose of my post. The point is that the kit was flawed new from the box. There are legal issues of liability for putting the matter right and legal action to this effect is curently in progress. For this reason I am only interested in hearing of specific examples of this product defect to gauge how widespread it is. General commentary is of no assistance to my case. So any examples that anyone can provide would be most welcome.
I'm guessing that the pump in your picture is about ~1Hp, would that be right? How deep have you suspended the Ejector-head? Is there ice or snow at your location?
Cheers.

 

[Valveman]

That pic is just one from a customer review. I have no idea how deep the ejector is. But it can be as deep as needed as long as the pump is sized accordingly.

I am just saying there is no defect with that injector if you were installing on rigid pipe. Did it come with instructions for installing on poly pipe?

 

[xylstra]

Hi Valveman,
Understood. The use of rigid pipe is peculiar to America and similar latitudes, I suspect due to the seasonal prevalence of ice and frost, code compliance issues and traditional practice. In Australasia (I'm in New Zealand) this practice is unheard of. All Ejector-Head installations are exclusively suspended with flexible PE pipe, double-clamped with industrial grade s/s hose clamps.
Such "instructions" as there were are written in the usual 'chinglish' but the pipe type is not stipulated.
There is no real mystery about the defect. As an engineer I read magazines like "Model Engineer's Workshop" and Model Engineer". You don't have to browse too hard or wait very long before some author describes his 'fix' for a Chinese-made machine-tool design/manufacturing fault - one that made my eyes pop was a tail-stock whose axis was not co-linear with the spindle (Quality Assurance inspection, what's that?!). This jet-pump is a small volume part of Taifu's range so is probably sub-contracted out and the Ejector-Head probably sub-sub-contracted out. The defective connector-pipe measures ~160mm long - think how many times in life you've mis-interpreted a '6' for an '8' or vice-versa due to bad hand-writing or a smudgy drawing. 180mm would be about right so after the dust settles I suspect it will turn out to be something as silly as the machinist getting the number back-to-front and likely the receiving 'inspector' (brain not plugged in!) using the same wonky drawing.
My day in court is May 8th, so we'll see.
Cheers for now.

 

[Valveman]

I understand. I have gotten some Chinese stuff off the Internet and all you get is a picture. Had to figure out if it would work and how to use it on my own after it showed up. Everything is "subbed" out. What you get this month will be completely different than what you get next month. I can't imagine going to court for something as trivial as this.

As an Engineer, if you want to fight a good cause in court. go after all the manufacturers who claim their VFD saves energy. This is absolutely not true. Just adding the VFD decreases efficiency by 3%-5%. Then anytime you vary the speed of the pump, you are getting fewer gallons per Kwh, not more. Yet they sell 27 BILLION dollars worth of VFD's every year on the false pretense that they save energy. They will show you the amps needed to spin the pump and motor will reduce by 50% when using a VFD. But they fail to mention that actually increases the cost per gallon by up to 500%.

 

[xylstra]

I understand. I have gotten some Chinese stuff off the Internet and all you get is a picture. Had to figure out if it would work and how to use it on my own after it showed up. Everything is "subbed" out. What you get this month will be completely different than what you get next month. I can't imagine going to court for something as trivial as this.

As an Engineer, if you want to fight a good cause in court. go after all the manufacturers who claim their VFD saves energy. This is absolutely not true. Just adding the VFD decreases efficiency by 3%-5%. Then anytime you vary the speed of the pump, you are getting fewer gallons per Kwh, not more. Yet they sell 27 BILLION dollars worth of VFD's every year on the false pretense that they save energy. They will show you the amps needed to spin the pump and motor will reduce by 50% when using a VFD. But they fail to mention that actually increases the cost per gallon by up to 500%.

 

[xylstra]

Hi 'Valveman',
That's not the only thing they don't tell you about VFD's , in fact, many of the buyers don't even try to educate themselves about some important technical issues ..... quite a few make the fatal error of retrofitting VFD's to old or non-compatible motors thinking it's all just plug-and-play. WRONG!! Old motors usually have lower insulation-class windings which means that they are prone to 'punch-through', i.e. the insulating coating has insufficient dielectric strength when subjected to the transient voltage spikes and other high-frequency switching artefacts generated by many VFD's (in spite of manufacturers claims to the contrary). But it gets worse: the bearings are prone to premature failure caused by micro-discharge sparks (same as EDM - Electric Discharge Machining) which results in surface erosion unless the bearing system is specifically designed to accomodate VFD's. So, the motor burns-out and the ignorant user wrongly blames the VFD.....
By the way the Ejector-Head issue is only part of a number of complaints I have concerning pumps sourced from this particular supplier. In New Zealand we have what we call the "Disputes Tribunal" (a sort of 'el cheapo', 'wild-west' quick-draw complaints resolution process) - very cheap and the rule is: no lawyers are permitted. Even without the tangible product problems, just for the way this particular supplier has messed me around I am happy ot do it just for the sheer satisfaction of being able to shove their head up their backsides. Pity I couldn't bring a camera into the hearing - the picture of their face would be worth hanging on the wall!
Cheers.

 

[Valveman]

Thanks xylstra!
You are right on the money about VFD's. The one thing that really bugs me is people thinking VFD's save energy when they do not. Just adding a VFD decreases the efficiency by 3%-5% because it takes that much energy to run the VFD itself. Then the more a VFD slows a pump down, the fewer gallons per Kwh it is producing, not the other way around. But everyone sees the amps needed to spin the pump and motor decrease and thinks they are saving energy. They don't understand the drop in amps and drop in flow rate is not linear. The flow drops off much faster than the horsepower, so reducing the pumps speed with a VFD always increases energy consumption.

I could use some help here if you wouldn't mind explaining that again?
http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/aft/83335/afv/topic/afpgj/5/Default.aspx

Thanks
Cary

 

[xylstra]

H

Thanks xylstra!
You are right on the money about VFD's. The one thing that really bugs me is people thinking VFD's save energy when they do not. Just adding a VFD decreases the efficiency by 3%-5% because it takes that much energy to run the VFD itself. Then the more a VFD slows a pump down, the fewer gallons per Kwh it is producing, not the other way around. But everyone sees the amps needed to spin the pump and motor decrease and thinks they are saving energy. They don't understand the drop in amps and drop in flow rate is not linear. The flow drops off much faster than the horsepower, so reducing the pumps speed with a VFD always increases energy consumption.

I could use some help here if you wouldn't mind explaining that again?
http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/aft/83335/afv/topic/afpgj/5/Default.aspx

Thanks
Cary

Hi Cary,
Thanks for the invite-in but I've got too many other issues on the go at the moment but I'll give you with some useful ammunition to broaden the debate: Inverter-Drive Heat-Pumps. These are marketed and sold on the lie that they will lower your energy costs .... so the poor fools swallows it hook, line and sinker. Things are nice, cosy and warm for a month and then they get their first electricity utility bill: WHAT!! - their useage has exploded (along with their wallet!). Mainly for many of the same reasons you allude to with respect to VFD water pumps. I am a regular reader of "Silicon Chip" magazine and not infrequently their are reader complaints over this issue in the mailbag section. Many owners bitterly regret the installation and out of frustration en-up manually switching on these thieving units only as required. Try GOOGLE searching the issue and contact the American Consumers Institute who I am sure will have come across it and likely have done comparative testing nd other investigations.
My own water woes have suddenly become worse with the visit a couple of days ago to my doorstep by a "hired gun" representing some rich pr@#**k who intends to start up a massive kiwifruit growing operation nearby (950m) with the intention of sinking not one, but 3 new well bores and advising me of the possibility of its effect on my well's water level. That same rick pr@#**k hasn't even the common courtesy of knocking on my door to show his face and say "hello" and introduce himself - instead he sends his 'henchman' to do his dirty work for him. I've no doubt me and my neighbours will be giving him the 'welcome' he deserves!
Cheers for now, Andre.

 

[Valveman]

Thanks again! I will check those out. The whole world is being fooled into thinking a VFD saves energy. I guess it is true, the bigger the lie the easier it is to believe.