Flex 6xxx Fan Replacement

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  • Question
  • Updated 4 months ago
  • Answered
There has been great concern about fan failure and replacement in the fgpa fan speed thread.  That thread has gotten almost impossibly long and difficult to follow.  

The concern of late has been about acquiring fans and DIY replacement.  K2CB has been kind enough acquire fans at a favorable price so acquisition is not a problem.  Replacement is the next hurdle.

 The concern expressed by Flex re DIY fan replacement is the concern about damaging the chip due to the fact that the adhesive is so STRONG.
The other concern expressed by Steve is difficulty replacing the shroud.  It doesn't look too difficult so long as you are extremely careful getting all the tabs aligned properly.

I hope someone (Flex?) will post detailed instructions.  Meanwhile my  4 year old 6500 has been been cruising along with no problems but, in an abundance of caution I have ordered 2 spares.

Hopefully,  Steve will post a failure rate of these fans so we will have an idea how real the concern about fan failure really is.
Photo of Gene - K3GC

Gene - K3GC

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Posted 1 year ago

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Photo of Steve - N5AC

Steve - N5AC, VP Engineering / CTO

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Official Response
As you may be aware, the original fans used on the CPU and FPGA parts inside of the shield in the FLEX-63/65/6700 radios have been failing prematurely.  After investigation, we believe that these fans will continue to fail over time in the field (it is not a lot problem).  So while they could be replaced with the same model fans, they will all have a similar MTTF to the existing fan, which includes premature failure.  If you have already or plan to replace your existing fans with the same manufacturer fans, you are likely to experience the same failure rate as the original fans in approximately the same time-frame since it is the same fan from the same manufacturer.
We have a ordered a custom fan from another manufacturer to replace the originally selected fans.  The fans are currently in production and we will let everyone know when they are available.  At that time, we will transition to only replacing fans with the new ones.  These are a higher cost, single-piece fan/heatsink assemblies and so the old heatsink/fan must be removed from the IC before the new one can be applied.  Improperly removing the old heatsink can result in a damaged IC and/or a damaged PCB, both of which require substantial cost to remedy.  While we would prefer to have a field-installable option, we were unfortunately unable to find one.  Your radio will need to be returned to FlexRadio for this service, if required.

We will post here again when the new fans are available.  For most of you, I would not recommend prophylactically replacing the existing fan if it has not failed.  If you plan to be in an area that is remote and replacing the fan would cause an unusual inconvenience, however, you may want to replace the fan before it fails.  This is an individual decision based on your tolerance for being without your radio when it needs to be serviced.

To simplify the service, if you have just a fan issue or need just the fan replaced, we will replace both CPU and FPGA fans, check out your radio and return for a fixed cost of an hour of bench time (currently 99USD).  We always perform a test on customer radios when they arrive in the shop and if other issues are found, we will contact you with any other issues that are found and the cost to repair, if applicable.  This fee is for an out-of-warranty radio.  If your radio is in-warranty and has a fan error message, the repair and return shipping fall under our warranty policy.  

For completeness, please note that we are not aware of any issues in the side fans of any of the FLEX-6000 radios and these fans do not need to be replaced.  The new FLEX-6400 and FLEX-6600 radios no longer use individual IC fans, instead using a single larger, slower moving fan along with mechanisms to ensure all parts receive air.