MCP35x noise level

[Genny]

Some time ago I purchased an H20-320 edge from swiftech that has an integrated res and MCP35x pump. My flow rates weren't as great as I'd like given that my loop has grown quite a bit, and if the pump was ramped up above 30-40% the noise level was too high for my liking.

Long story short, I added a second MCP35x to my loop and the new pump is WHISPER quiet. Even at 100% I can't hear it over my Gentle Typhoons. So what gives? Why is the original MCP35x so much louder? I'd wager the original one is subjectively louder by a factor of 10.

 

[Guest]

wecome to the wide world of watercooling friend. As far as pumps are concerned it doesn't matter which distributer you purchase from sometime's: like with purchasing cpu's that are the same mhz some are brillant and some not so much but they do what they intended on doing which is work. So it sounds like the second time you got a pump it was of your standard. enjoy!

 

[Guest]

in depth answer would be that a bearing or axle or the balance of the impeller is loose,has a *burr, or is improperly balanced.
*(burr is extra metal,plastic or material of sorts that has not been trimmed of the piece of the product during or after injection molding if its plastic,casting if it is metal or just not trimmed, sanded after it was CNC'd.)

 

[rubix_1011]

It could be manufacturing defect...was it always that loud? As for flow...the MCP35x should be able to push through about any loop with good flow...it's one of the best pumps out there right now for under $150. What was your loop before and after adding the 2nd pump? Could be a few things causing your issues...just trying to gather more info before starting to diagnose.

 

[boiler1990]

It could be manufacturing defect...was it always that loud? As for flow...the MCP35x should be able to push through about any loop with good flow...it's one of the best pumps out there right now for under $150. What was your loop before and after adding the 2nd pump? Could be a few things causing your issues...just trying to gather more info before starting to diagnose.

The MCP35X is really only second to the MCP655 Vario at the enthusiast level (1000 LPH vs 1200 LPH), so I'd honestly be astounded if you had enough stuff to slow the pump down significantly

I've heard that the MCP35X is supposed to very quiet. My MCP655 would be almost silent if it weren't for the bubbles I can't get out yet.

 

[rubix_1011]

Yeah, but the MCP35x pushes more head, which is a better number over flow if you had to choose. (Can't go wrong with either, to be honest).

And yeah...my MCP655 is very quiet...and its about 6 years old...I can't hear it unless I actually put my ear up to it. The DDC pumps are typically quieter...

 

[orangejuice789]

@ boiler the 35x is arguably better than the 655 due to its higher head pressure, I guess it depends on the restriction in your loop though... for instance, if you are running SLI, CPU, and NB blocks the 35x may be more suitable, whereas if you are just running a CPU loop, the 655 may be more suitable... <- These are just assumptions though to emphasize how head pressure and flowrate are seperate factors.

EDIT: Ugh, Rubix.

 

[rubix_1011]

 

[Genny]

It could be manufacturing defect...was it always that loud? As for flow...the MCP35x should be able to push through about any loop with good flow...it's one of the best pumps out there right now for under $150. What was your loop before and after adding the 2nd pump? Could be a few things causing your issues...just trying to gather more info before starting to diagnose.

Three rads, three blocks and two 90 degree fittings. The reason I wasn't happy with the flow rate is that I kept the pump at around 30% PWM or below due to noise level. New one I can't even tell it's on really.

The original MCP35x was always relatively loud but it is nearly silent at 30% or below. Watching videos of noise tests on youtube...some sound similar while others do not at all. It lead me to question whether the new one is just stuck at 10% It doesn't grind or anything like that...it's more similar to a mechanical hum or whine. Unfortunately I don't have enough experience with these pumps to determine which is which...


In this video if you skip to 6:40 that's about comparable to the sound of the original pump at full speed.

 

[boiler1990]

Yeah, but the MCP35x pushes more head, which is a better number over flow if you had to choose. (Can't go wrong with either, to be honest).

And yeah...my MCP655 is very quiet...and its about 6 years old...I can't hear it unless I actually put my ear up to it. The DDC pumps are typically quieter...

That is true - the higher pressure is better. I still think the 35X should be able to handle the rads/blocks. I had 2 rads and 2 blocks on my XSPC X2O 750 (arguably crappy compared to standard DDC/D5 pumps) and it ran/cooled fine.

 

[Genny]

I found my problem.

It's leaking slowly right here. Pump must be sucking air as a result making it so loud...

Sigh...RMA here I come.

 

[boiler1990]

Damn, that sucks. At least you won't have any down time in the loop since you have the second pump, and you can RMA this one.

 

[rubix_1011]

Bearing failure...that's what comes to mind first.

When you first started filling/priming the system, did you run the pump for any amount of time where it wouldn't have any water to pump? The bearings on these pumps are water lubricated and cooled and if the pumps spin without water, they very, very quickly burn out or are damaged.

 

[Genny]

Bearing failure...that's what comes to mind first.

When you first started filling/priming the system, did you run the pump for any amount of time where it wouldn't have any water to pump? The bearings on these pumps are water lubricated and cooled and if the pumps spin without water, they very, very quickly burn out or are damaged.

No, I was very careful to never run dry, however, the H2O-320 edge on its own is a royal bitch to bleed. (half the reason I decided to get another pump and reservoir, just to make things easier on myself). You'll hear it hitting some pretty nasty air pockets for a while... I don't think having the reservoir and pump level with each other is necessarily ideal, however I did tilt the case each time starting up to allow the reservoir to be above the pump.

 

[rubix_1011]

Did you mount it so that the pump was always at the bottom and able to draw water? Mounting upside down would result in the inlet port would draw air, but it definitely doesn't sound to be the instance here.

 

[Genny]

Did you mount it so that the pump was always at the bottom and able to draw water? Mounting upside down would result in the inlet port would draw air, but it definitely doesn't sound to be the instance here.

It's mounted horizontal in the case like this

It's considered a valid way to install as long as you tilt the case so the res is higher than the pump during the bleeding process.

 

[rubix_1011]

I agree, its a valid mounting solution...just wasn't sure if it contributed to premature bearing failure, or you just got a lemon.

 

[Genny]

I agree, its a valid mounting solution...just wasn't sure if it contributed to premature bearing failure, or you just got a lemon.

Yeah it's certainly possible...it'll howl like a banshee for a few hours as it's hitting air pockets after the initial fill. The filling and bleeding procedure was much simpler with a standard res and pump solution.

 

[rubix_1011]

I've heard a lot of people raving about these Edge combos...but maybe they were all vertically mounted. Also haven't heard anything but excellent reviews on the MCP35x's...concerning.

A pump definitely shouldn't be making noise like that...should be a very quiet humming.

 

[Genny]

Best answer selected by Genny.