New mac Fans going

A mate has just got a new iMac from Apple a refurb.

However the fan is going 100% all the time at over 4k rpm

I installed a HDD fan tool and from this found it was the system fan not the HDD fan i think.

Anyway I tried the Apple reset by unplugging for 15 seconds plugging on 5 second and starting all the same thing.

However what i noticed was that it only started to run when he clicked into the profile.

I created a new blank standard user account and logged onto this and no fan well not 100% all the time.

So before i go and delete the profile etc. anything anyone can suggest what is causing this?

I did call apple but their only soloution was to give a full refund and not fix it;

It sounds like there is a runaway process that is making the machine run warm. I would open Activity Monitor (Applications => Utilities) and sort the process list by CPU utilization. That should give you a clue as to what process is spiking utilization.

Culprits could be things like animated wallpaper or a poorly written program or dashboard widget. Finding out the name of the process should help us isolate the issue.

Since the machine is a new refurbished model, it's probably best to go ahead and delete that account and just use the new one you created. And of course keep a close watch on the Fan speed. Fan speeds in an iMac are controlled by heat sensors - and there are three fans. HD, CPU, and Optical drive.

If any of the fans begin to act up again, get a refund from Apple or have them send out another refurbished unit.

Normal Fan speeds for a newer iMac:

CPU = ~1200 RPM

HD = ~1100 RPM

Optical = ~1000 RPM

I did have a look at the Activity monitor and nothing in there at all causing any issues as per using up a lot of CPU etc.