I had a valve that was going in the espresso machine. I don't really know much about the guts of an espresso machine. Talked to my roaster about it, he had a spare valve which he sent over and he gave some advice about replacing it. It took me about ten minutes to change out the valve after the machine cooled down. No more steam leak. It's and old machine but it works great. It's even got some aftermarket improvements that my ridiculously ancient espresso mechanic souped it up with. My roaster says that the average coffee shop spends at least $500 a year on equipment repair, with the most common cause of failure being a blown circuit breaker ($70 please). So far I'm in for a $28 valve in a year and a half. I can fix the mechanical bits of my coffee or espresso grinders and know a bit about the espresso machine. I guess I'm making it a goal to never pay anyone to fix my equipment and do it all myself. I might break that vow if it's an electrical problem but maybe not.
My friend has been working at a pizza place for at least the past 10 years now. And this summer the dough mixer broke. It was really fun hearing him talk about going around town, finding the proper bearing and trying to put it back together. I guess for him it was a welcome change from the routine. And since repairs on these industrial machines are so expensive (not talking about buying a new one!) the boss was okay with it. He did fix it after 2 days! Now the oven broke. I guess a new adventure begins!
I truly can't imagine maintaining an espresso machine in a commercial setting. I bought a La Marzocco when I moved outside of convenient driving range of any coffee shops, and it made great espresso, and I kept it in working order for 4 years, and then I just couldn't be bothered anymore and I drink aeropress or cold brew now. I care enough to drive two hours every month or so for green beans and to roast them myself, but keeping the La Marzocco working was way more trouble than it was worth.
They are pretty stable if you keep them on all the time. Turning them on and off, heating stuff up, cooling it down, putting it under pressure and depressurizing them causes more wear and tear than using them and leaving them on all the time. At least that is what I'm told, it's all peasant lore and I do what I'm told.
What typically fail on these things? Is it bearings, reservoir hosing and valves, washers, things of that nature?
Gaskets on the group heads are going to go first. I changed mine out after one year before they had a chance to leak pressure. They are cheap, more like maintenance than repair. I think I'm going to need to replace a valve or seal on one of my steam wands before long, seems like it isn't sealing as well as it should. Looking at the valve I replaced I think it might be original, so around twenty years old. Puro cafe is mildly corrosive to metals, so every thing down stream of the group heads is going to go eventually. My roaster has the copper connector to his drain corrode and leak a few weeks back. Another shop that my roaster sells to had some kind of water sensor fail recently. I think old espresso machines are like old cars, anything could go. If there is no water filter on a machine and the water has any mineral content than it's going to fuck the machine up badly. I think it was ecib that sent me some photos of a machine who's boiler had more limescale than open space in the boiler. If you don't keep your machine clean you'll make terrible espresso and it could interfere with the general operation. Lots of equipment chit chat on my roasters blog, most of it about coffee roasters but a bit about brewing equipment. http://www.couriercoffeeroasters.com/wordpress/