I wanted to know if anyone's experienced this problem before. Also, before I start dropping money on my Aurelia, I wanted confirmation if it's the water pump.

I bought a used NS Aurelia for a steal and overall it was in great condition. One thing however, when I got it hooked up and turned on is every time I pull a shot, the machine makes a loud whirring noise. It sounds like it could be the water pump that's just working, but it's definitely very audible and nasty sounding. Not only is this embarrassing, but it just sounds wrong.

Any suggestions? 

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had that problem on my pump as well i just open the back of the motor and there is a little fan ther and it was flaping on the side of the motor stand.

Nice, thanks! I'll try it and see if that's the case.

Do you use the Aurelia as well?

olivier dutil said:

had that problem on my pump as well i just open the back of the motor and there is a little fan ther and it was flaping on the side of the motor stand.

No Was on my Gb5 but pump motor are almost all the same

There could be a number of issues so don't go ordering parts just yet.  The first thing I would look at is the water pressure guage.  Pumps can make awful noises when the incoming pressure is way to low.  Most locations have water pressure that "sits" somewhere between 3 and 6 bar.  When the machine is not running the water pressure guage will read the site pressure.  The next thing I'd look at is what the pressure guage says when you pull a shot.  Pumps that are turned up to a very high pressure will make an awful racket, as well.  You want to see the pressure indicator somewhere around 9bar.  If it's at 11 or 12 when pulling a shot then decreasing the presure adjustment might easily make the noise go away.  Also, does the machine make the noise regardless of whether the portafilter is loaded with coffee?  What does the pressure guage read when you engage a shot with the portafilter empty?

I'd say check the stuff Mike mentioned before you go cracking into the motor. That may well have been Oliver's problem, but that isn't a problem I've ever run across, so I think other causes are more likely. I've replaced more pump heads than I can count, but only 2-3  motors (all of those being the result of failed pump seal leaking and corroding the motor bearing).

First step - verify that the machine's main shutoff valve is fully open (this is the valve that is between the braided supply line and machine pump). The black plastic handle should be in line with the valve housing. If it isn't, make it so and try a shot. Another thing to check - is the supply line kinked, flat-spotted, or under one of the machine's feet? Facepalm optional here (I have seen both of these be the problem).

On the "adequate water supply" item - verify that there is adequate pressure AND flow. Pressure should be 2-5 bars at idle, like Mike said. HOWEVER the supply must also be at least 35 gallons per hour (.6 gallons per minute). To verify this, turn off the water to the machine, disconnect the supply line where it feeds into the machine shutoff valve, then turn the shutoff back on and time how long it takes to get half a gallon of water. If it takes longer than 50 seconds then you need to increase the flow of water to your machine. Failure to do so will lead to pump failure.

Too little water flow is often caused by clogged water filters or when people use those little brass saddle valves to tap into an existing water line. Or sometimes people just forget to fully turn on their shutoff valves.

If your pump pressure is too high (12+ bar) and won't adjust lower, you have a pump issue. Often the pump bypass (which controls the output pressure) freezes up with time, forcing water through the machine's expansion valve and making lots of noise.

If you do choose to adjust your pump (especially lower), be careful. That brass screw is not terribly long, and if you unscrew it too far the water pressure will blow it out - giving you and your machine internals a good shower AND blowing the pump innards to the far reaches of your cafe. To be safe, I'd note the pressure then turn off the machine and main water valve, back the screw out 1 turn, then back in a quarter. Turn the valve and machine back on and check pressure. If it went down, repeat until you're at your desired pressure. If not, try again. If you see no response after making several adjustments, you've found your problem.

One other cause of high-pitched noises when pulling a shot is a partially-clogged orifice. That's more of a whining noise though.

Hope that helps. Please post back once you've found the problem?

Thanks all for the input. Checked the pressure and found mine was a little high. However after adjusting to 9 it still made the noise. Brady, you may be on something. The noise is a somewhat higher pitched whirring noise. Could it be a clogged orifice? How do I go about checking that?
There are two orifices for each group, one at the flow meter and one up at the grouphead. Checking them requires taking the tubing apart. If your Aurelia is the WBC model it will make a higher pitched sound anyway because it uses very small orifices, different from the standard Aurelia. The first one is on the "out" side of the flow meter, you'll have to take the meter out to get to it but you should see a small hex head inside the long fitting that has a small hole in it. That's it. You can also open up the top of the flow meter to check for debris, as well. I am assuming you know enough to unplug the machine and turn off the water. When you start getting into the lower area of the plumbing and taking stuff apart just know that the heat exchangers will empty themselves and that water is hot. Be prepared with towels and flat trays to catch the water. The second orfice is on the upper of the two fittings on the back side of the grouphead. If there is buildup this is where it is likely to be. Scale likes joints like this one since the water is so hot up here and when entering the grouphead can change temperature dramatically causing the scale to pricipatate out and build up at the fittings and inside the grouphead itself. The orfice itself is the same kind of hex head screw with a tiny hole in the middle of it. You'll have to take the whole pipe off that comes from the top of the heat exchanger to that top fitting so you'll have to deal with some got water. You might ask the people you bought it from how they descaled the unit and if they descaled the heat exchangers and group heads. The scale up there can be really dense. I've had to drill out Aurelia heads when the Citric acid wouldn't clear out the water path ways.

The reason I asked about how the machine sounded and what the guage reads with empty portafilters was to help diagnose this issue. If the gauge reads around 9 with no coffee in the portafilters then you know that you've got a restriction before the water gets to the portafilter. A clear pathway will put the gauge a bar or two above the site pressure when the pump comes on but not much more than that. Checking for adequate water flow before the machine is critical, too.

Have you owned or worked on a machine with an internal pump before?  I ask, cause they are way noisier then say a GB5 with an external pump that is usually mounted under the counter and out of sight.  I have a NS Program Plus in the basement and when working on it I forget how much noise those things make in comparison to a LM Linea.  Or maybe I'm oversensitive.  I recently performed a Pumpandectomy (relocation to under the counter, in case anyone doesn't get the joke) on a Brasilia for a similar noise abatement issue.  

If non of the above applies, then carry on with what the boys have already mentioned and report back.  

Thanks guys for the awesome responses!

Mike, I'll give it a shot, but it seems like I'm eventually going to have to do a full descale? Also, sorry about missing the empty portafilter question. I'm going to need to check on that again and I'll let you know. 

Scott, I've worked on the GB5 before, and I'll agree, that thing is super quiet. The thing is, it just seems like my Aurelia is so much louder than the others. Maybe it's just one of those things no matter which Aurelia I check, mine will always sound worse because it's mine. 

I'm more of a coffee roaster with a coffee lab setup that has an espresso machine. So when it comes to the espresso machines, I'm a noob at. Now if we're talking roasters then that's another story...

I've noticed the "whirring" sound on many aurelias.  I think it is due to the pre-infusion chamber above the group.  NS will sell a "blank" that you can put in there.  This helps with the whirring noise as well as cleaning out the jets.  Blocking the pre-infusion chamber will also help with the "drip after" the shot is pulled.

If its a noise that just starts and doesn't change when the pump is running then it could be the pump.

Hey, here's another thought... is anything touching the pump or motor? Is the braided stainless supply line touching another part of the machine? The motor is isolated from the machine with rubber bumpers, but if there's physical contact somewhere that might be the cause of your noise. Something worth looking at.

All very good suggestions! I guess I'll have to do more digging. I'll keep you guys updated from what I find!

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