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First build, first fail.. PWM pump runs at 100%

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Mak150

New Member
Joined
Jul 29, 2016
Hello everyone!

So this is my first watercooling build, ordered this pump combo https://www.ekwb.com/shop/ek-xres-140-revo-d5-pwm-incl-pump

I set it all up, had a few things I didn't consider, a right angle and barbe fitting for the radiators etc.

Anyway, got it all setup, set the pumps PWN connector to the motherboards CPU fan header. Upon turning it on, I noticed the pump ran at 100% use. filled the entire system, ran it for a few minutes. Nothing.

I switched the connectors around, tried a few different headers. But every restart yielded the same result, it simply wont regulate the speed.

What can be done here? Is the pump faulty? Its quite loud :(
 
OP
M

Mak150

New Member
Joined
Jul 29, 2016
I just saw one of my fittings leaked, I will check back in a bit.
 

Jeff G

Member
Joined
May 22, 2016
I'm pretty certain the Molex connector is for leaking testing, it runs your pump at 100%. Only the PWM connector should be connected if you want to control the speed. Should be in the manual for the pump.
 
OP
M

Mak150

New Member
Joined
Jul 29, 2016
I'm pretty certain the Molex connector is for leaking testing, it runs your pump at 100%. Only the PWM connector should be connected if you want to control the speed. Should be in the manual for the pump.

I dont think so, the molex only has a red and black wire on it, they're pretty thick indicating main power comes from that.

The fan connector on the other hand, does not receive power from the mobo it seems.

Leak was caused by a too small tube being used coming off the cpu, replaced with one slightly longer and that sorted it.
 

Jeff G

Member
Joined
May 22, 2016
This is from ek's site:
Default behavior: Runs at 100% duty cycle when no PWM feedback signal is present

Looks like its not sensing the PWM signal.
 
OP
M

Mak150

New Member
Joined
Jul 29, 2016
This is from ek's site:
Default behavior: Runs at 100% duty cycle when no PWM feedback signal is present

Looks like its not sensing the PWM signal.

Must be a broken pump then, as I connected a couple of fans to the same header afterwards, that ran at 800 RPM after it booted.
 
OP
M

Mak150

New Member
Joined
Jul 29, 2016
Case closed. I updated bios to latest version, made sure all fans was set to PWM and it worked.
 

GTXJackBauer

Water Cooling Senior Member, #TEAMH20HNO
Joined
May 22, 2011
Location
USA
I'm pretty certain the Molex connector is for leaking testing, it runs your pump at 100%. Only the PWM connector should be connected if you want to control the speed. Should be in the manual for the pump.

This is incorrect. The Molex is for power and the 4-pin is for read out and PWM for control.

OP, make sure you do a leak test before firing it up! You're lucky you haven't blown anything while finding a leaked fitting.
 

Jeff G

Member
Joined
May 22, 2016
This is incorrect. The Molex is for power and the 4-pin is for read out and PWM for control.

OP, make sure you do a leak test before firing it up! You're lucky you haven't blown anything while finding a leaked fitting.

Yeah, I read it wrong. Looks like Molex is for constant power, while the PWM is what regulates the flow. With no PWM input, it defaults to 100%.
 
OP
M

Mak150

New Member
Joined
Jul 29, 2016
This is incorrect. The Molex is for power and the 4-pin is for read out and PWM for control.

OP, make sure you do a leak test before firing it up! You're lucky you haven't blown anything while finding a leaked fitting.

It turned out, that while flitting with the new radiator at the top, I made the hose from the CPU to the radiator a bit too short.

I made a new one, and it gave a much nicer bend and fixed the leak :D

Glad I used the toilet paper method to check for drips haha.

After the switch I ran it for 24 hours, and its all good!