lundi 25 octobre 2010

Case #1954 Sherlock?


Case #1954

Unit: Jet-Tech F18dp
Paying attention is important in this job. It's a bit like playing Sherlock Holmes and trying to find who done it. Or what done it in this case.
Often the smallest detail is important. In this case the answer was right there in front of my eyes. All I had to do was look and listen.
The machine is a Jet-Tech model F-18dp under-counter dishwasher. The F-18 is a good Italian machine. In Europe it carries the model name CF50. It is made by Adler near Milan. The place was a nice Italian restaurant. I received a call from the chemical distributor. They were in a bit of a pickle. They were afraid of losing the account if the dishwasher could not be fixed. They had sent another technician and he failed to find the problem. The problem reported was the unit's wash pump was defective, and a new one was needed.



Whenever someone sends me after another technician, I do what I always do. I start from the beginning. When they told me the wash pump needed to be replaced I was a bit skeptical. Adler (Jet-Tech) uses one of the best pumps on the market. It is made by FIR  and short of dipping it in water or have a chemical spill on it, it's going to outlast the rest of the machine. Almost.
Anyway, when questioning the operator, he told me the unit would wash occasionally. So it was an intermittent problem. I needed to hear this thing run. By the sound the motor of the wash pump would make I could determine if the pump was indeed defective.
I started by draining the machine. Going through all the sequence of the unit will help determine if I was dealing with one or more problems. I let the machine fill up. The heat kicked in properly. I pressed the start button to get the wash pump to work and it did. The sound was a solid, continuous pumping action. That pump was good. Then the sound changed. I stopped it right away. I took the top cover off and put my amp probe on the wash pump line. Tried it again and the amps went way up. I was thinking a bad capacitor might be the cause. I changed it but the problem remains. It was getting late, 8 pm or so. I was not convinced the pump was bad but right then I couldn't prove it. I took the decision to take it out and bring it to the shop for closer inspection. When I took the rear panel out, I noticed what the last technician did. Reconnect the detergent bulkhead fitting.
In the morning, I put the motor on the bench and tried it. It purred. There was nothing wrong with this pump. I went back to the restaurant and put the pump back, totally convince the problem was elsewhere. It was and not that far. I paid a closer look at the repair the other tech did. Before the operator noticed the chemical fitting was broken a generous amount of detergent had leaked down on the wires. Yes, the wires had been covered with dried detergent. I should have spotted that the previous night but I missed it. I had seen this before. Chemicals will destroy the insulation on the wires and on occasion break the connection. It's exactly what happened with the wire for the capacitor which would be touching sometime. The best course of action is to change the entire wire harness. The next best thing is to clean the wires thoroughly and re-insulated them, repaired the broken connection.
This was done and the machine worked very nicely.
Conclusion: It’s not always good to work too long hours. As a general rule, I stop around 5pm. I mean, what’s the point of working late if you're going to make mistake and have to return. And I am not Sherlock Holmes.

lundi 18 octobre 2010

Case #1783 A clean situation


Case #1783

Unit: Alfa Vergina

If you work in this field, this story will not surprise you.
The service call came in from the distributor. It was a fairly new machine but it was not working well, not washing properly. The machine is an Alfa Vergina, manufactured in Greece. It is well built and well put together. The place is a nursing home, new construction. The building was not six months old at the time. Everything in it was new. 
When I spoke with the people in charge and the people using the equipment, I couldn’t get a straight answer about some very simple operations.
I was trying to find out what they meant by not washing properly. They showed me some dishes. Okay, the dishes were not exactly clean but something was bothering me. Next I was trying to find out how often the dishwasher is cleaned. I got some blank stare. This kind of unit needs to be drain at least once a day. I turned to the dishwasher and started inspecting it. The unit was in use and was full of water. I saw something in the water, and the pump screen was not set properly so I decided to take out my light and look inside.

Anyone can tell me what’s wrong with this picture? I am not talking only about the clogged jets.
I pointed out to the people there that this amount of cutlery in the wash water is not acceptable even by a long shot. Of course I was speaking to the wrong person because those two were not in charge of cleaning it. Sigh!
I proceeded to clean the dishwasher in order to make sure this was the only problem. I filled the sink with what was inside. And yes, it was the only problem. 
To top it off they refused to pay for this service call on the premise that it was covered by warranty. Funny isn’t it. I took some pleasure in explaining that warranties from any manufacturers would never cover this. 

In the end I was paid.

jeudi 7 octobre 2010

Case #1922 The Diamond Experience

Case #1922

Unit: Diamond TT550 585198

This was trial by fire. A lot of first things happened with this case. New machine, new supplier, new problem.
Let me give you the setting on this one. Customer bought this new dishwasher six month prior to this problem. The machine is an imported Italian dishwasher made by Colged. Good machine but a bit too fancy for the North American market. The customer's kitchen is so small that when the dishwasher door is opened there is no room to fart.
I had visited this customer on three earlier occasions for what seemed unrelated problems. First time, the machine did not drain. I found thick food stuff in the drain. The customer was not pre-rising the dishes for sure. Second visit, the rinse pump leaked. The mechanical seal failed on it. The distributor supplied me with a new pump and that was replaced. On my third visit, they had a similar problem to the first time. Because they were also using an old basket from an older machine, pieces of it, a peg blocked the drain.

Now here comes this case. The customer complained the unit would not work anymore, or work very erratically. After a few minutes, I found the electronic board had burnt connections on one of its terminals. I contacted the distributor’s support department and they provided me with a new board and no real explanation for the possible cause. Because the terminal was badly melted I improvised some connections on the new board. A week later they had the same problem. That's when things started to go bad. The distributor decided then to drop this dishwasher line, including warranty, tech support, everything. I tried at the time to plead this case with the factory in Italy directly and managed to get some technical help. They were not impressed with my improvised repair, blamed part of it and the other part they said that this kind of damage is likely cause by water.
Now I have a possible explanation for the problem but no one wants to pay for anything. Of course this dragged on for several months. I finally made an arrangement with the factory. They trained me. I received a lot of technical information. With all of this I offered to the customer to take the machine to my shop, fix it and bring it back. There would be no charge for any of it. Why? The way I saw it, it was an excellent occasion to learn, hands on, how this animal works. The reason for bringing to my shop was very obvious to me. In my shop I was able to literally strip it and study every component. Hopefully find if and where the water was coming from. I honestly thought the drain pump was drawing too much amperage. With all the crap it had to deal with, for me it was obvious.
On the bench, all the panels went. One by one, I check all the components for defect and damage starting with the drain pump. Well, it wasn't the drain pump. I looked everywhere for signs of water spots. I didn't see anything obvious. I only saw some traces from when the rinse-pump leaked.
I decided it's time for testing the machine with a new board. I was nervous because I didn't find the cause of my board failure. This time I changed for the proper connector (CN10) with the proper pins. For this test, the panel where all the components are is opened in order to see if something happens. Something did happen.
We turned on the unit. It did all the proper sequence for filling, temperatures all were okay. Through all of this I and my assistant are looking with a light for any signs of water leak or smoking wires but see none of it. Now it was time for trying the short wash cycle. This huge quantity of water shoots out from under the door, spraying all the electronics. Madly, we rushed to cut the power. Too late. Lost electronic board number 3. Well, you can imagine the mood I was in. Yes, I swore. More than once.
I realized a couple of things afterward. The customer never mentioned the fact the machine was spilling quite a bit of water. This, in sufficient quantities, can get to the electronic board underneath. It's so happened that the unit did not do this every time for them. It would happen on evening shift where the staff would use the dishwasher differently. I mean differently in a bad way. The day shift never had any problems with this unit only the evening.
It's not the first time that a customer does not tell me the whole story before I start. Anyway. I was left figuring out why that was happening. I knew for a fact that when the dishwasher was installed and first started it didn’t do this. It took me about a week before I finally contacted the factory and ask their opinion. The response was very quick and a bit surprising. They said it is the soft-start system that is blocked. "The what?”
During my training we covered the TT550 under-counter dishwasher quickly and focused on the TT750 hood machine. This was done mostly because they happened to have a TT750 but no TT550 handy for demonstration. There is no soft-start on the TT750. The soft-start system is a simple mechanism which allows the wash pump to draw air for a short period of time to dampen the full force of the wash pump. This is done with a small 1/4" tube connected to a small cylinder in the back of the machine. When the tube is blocked with crap, the wash pump deploys its full force and cause water to shoot out from under the door.
I took this system apart and cleaned it. It was indeed blocked. I put everything back. Put a new board. Covered it with a lot of plastic and started the machine. This time everything worked perfectly.
The machine was brought back to the customer. She told me that she would not let just anyone touch it. It's been working fine since.
Happy ending.

samedi 2 octobre 2010

Introduction

My name is Robert Marsolais. I am a service technician in the restaurant industry. I own and operate a small service company called Reparations Marsolais in Montreal. My specialty is commercial dishwashers, more precisely european made dishwashers.

In this blog, I will share my work experience. In this I hope to help out people with similar problems. I do not pretend to be an expert and if you find a mistake or a better way to do something, please, let me know.

Enjoy reading.

Robert