Some Things Just Really Cheese Me Off. . .
A poorly done repair is one of those things.
This week I received a NuTone IM4406 Intercom Master Station in for repair. It had a typical list of problems: No Intercom, No Radio, No CD, No Chime, No sound from the system at all, basically the clock kept time and it would display Radio Station readouts - thats' all it did.
Upon initial inspection, I noticed that there were markings on the circuit boards, markings that were made by another repair shop - another NuTone repair shop - and I knew which one . . .
I contacted the owner of the IM4406 and asked about prior repairs, he said that he had sent it in to another shop 2 years ago for basically the same problem. Hmmm.
I was shocked by what I found when I disassembled the set. During the prior "repair" 1 component was replaced and even that wasn't done correctly.
A single Voltage Regulator was replaced (a common problem) however the all important heat sink bracket was not added (something that is common knowledge - even 2 years ago) so the new regulator was doomed from the start.
So why is this so bad?
Lets look at what we know about this type of problem with a IM4006.
1. The original voltage regulator lasted about 15 years before it failed.
2. The improperly installed replacement regulator lasted only 2 years
Why?
The failed Voltage Regulator is symptom of the problem, no the problem itself. Yes, the regulator should have had a heat sink bracket when the IM4406 was designed back in 1996 - but even without the bracket, the regulator lasted 15 years.
Why did the replacement last only 2 years?
Because of what causes the regulator to fail: An ever increasing demand on it: Which is caused by the slow failure of other components in circuit.
Would this "repair" have lasted longer if they added the heat sink bracket - probably
Would have adding the heat sink bracket made this a proper and complete repair - Not Even Close -
The reality of repairing equipment that has to be shipped in to us and then shipped back to the customer is that the shipping costs are a measurable percentage of the overall total cost.
In the long term, performing a complete and through repair is less expensive than doing a minimal repair. The few extra dollars for parts is nothing compare to the time, effort and expense of have the unit repaired again 2 years later.
So, why was the original repair done so poorly? - My guess is that they simply don't care enough to do it right. . .
Here's a picture of what I replaced (inside the red box) the blue arrow points to the 1 part that the other shop had replaced.