Throughout the years as working as a software engineer, I picked up valuable engineering skills. What I did not realized is that, applying them can be challenging in unexpected situations.
A plumber came to our house to repair a water leak in our shower today. Initially we found one, Plumber A, through recommendation from our network, but maybe because he was too good so he was too busy to come, we waited a week, and went with another alternative.
Plumber B is less popular which is good in a sense that we can book him sooner, we were a bit skeptical at first, but since we want our shower fixed asap, we took the risk.
He took out the cold and hot shower knobs, a bit of moisture, but no leaks by surface inspection. Then he remove the shower tap at the top, put the pressure meter on, turn the knobs, result: losing pressure.
He quickly deduce that the leakage must be somewhere between the tap on the top and the knobs under, and in order to find it, he must drill through the bathroom tiles, starting from the bottom. He seems to know what he is talking about, the logic sounds reasonable, and I respect his expertise. I permit him to drill.
He was now thinking he might have enough time, because what we told him is that it was just a shower leak. He thought about a little, and decided to give it a go. He brought in a big drill from his truck, and then decided it was too big, then he brought a smaller one. Everything looks good to go, and he drilled. Our new shower tiles broke into pieces, a hole is done, most likely the water proofing is also damaged. Interestingly, no water, and dry.
He looked a bit puzzled, because this is not what he expected. Just in case, he pressure tested each of the knobs, seems still losing pressure. He now went out the front yard, and attempted to find the water meter and shut it down. I pointed him where it was, he shut it down, he now took out the knobs entirely and examine them front to back, problem found: one of the knobs looked damaged at the back but not at the front, so he missed it.
He replaced the damaged piece, and placed everything back. He was pretty honest about drilling the hole incorrectly and charged a lower rate for labour.
Now the shower is fixed, but with a hole in the tiles. What sucks is that fixing the hole is 5 times more expensive then fixing the leak.
What Went Wrong
When he concluded that there must be a leak between the tap and the knobs, I asked if there are any other cases that might cause the same situation, he said no.
Lesson 0: I should have stopped him, never trust experts blindly without analysing ground-up from fundamentals.
Lesson 1: Before doing anything that is irreversible, pause and think about the alternatives.
Lesson 2: Every variable parts of the equation needs to be examined thoroughly, don’t make any assumptions. I.e. The knobs need to removed entirely and check that there is no fault before concluding it is fine, and move on to drill the hole in the tiles.
Lesson 3: Experiences matter. Plumber B looks much younger that Plumber A. And when Plumber A examine the shower during his initial visit, he smirk and suggested to remove all the parts and replace them first and see if the problem is fixed, then check the water pressure or even drill the wall. His principle is do the things easiest first and he is right. He might even think this job is too little, and cannot even bother to come again.
What this translate to is that someone from a 12 week boot-camp is cheaper to hire and passes the technical coding interview, but the senior guy with years of experiences will most likely cost you less overall even his salary might be much higher than the boot-camp guy. Don’t cheap on the salary and value experiences.
6 times of the original fix cost.
Still far better that what we originally expected.
The wall was a brick wall so the water did not affect it.
We thought that it might be the water proofing instead of the shower leakage that went wrong, which means it could be substantially more expensive to fix.
I can learn what he had done from Youtube, it won’t worth my time and require to invest in tools and parts, which I will rarely reuse, but I will probably avoid drilling first definitely, so if it did it myself, I would save some money by trading off time.
Anyways, problem solved with a cost, and not the optimal way – the shortest and cheapest path. As a engineer this really bothers me a lot, a non-clean solution.