Ariston GL2.5 Electric Mini-Tank Water Heater

Excellent water heater as long as you do maintenance on it. I have been using this water heater for 5 years. At first I didn't know about the need to replace the magnesium anode (my fault as it is recommended in the manual) and used it continuously for 3 years. When I finally opened it up, the anode was totally gone. I cleaned the heating element with vinegar and scrapped off the scale deposit; replaced the spent magnesium anode with new one (bought 2 online); clean the tank as much as possible. Fast forward 2 more years and this time the anode barely has some magnesium on its core - see attached pictures after 2 years of usage and after maintenance. Again I clean the tank and heating element plus replacing the anode; I expect this water heater to last at least 2 more years. I rate this water heater 4 stars since I have to do maintenance so often.I hook this water heater to provide hot water for the master sinks only and we keep the heat low. I would consider our usage as light, ex: washing hands, face and brushing teeth. Therefore if you use this heater more or keep the heat high then I would recommend do the maintenance every year.Edit: After changing the anode, I was worried due to the Temp & Pressure Relief Valve kept leaking. It turned out, some debris got stuck in it. Just open the valve fully and flush it out a while and everything is fine (so glad I didn't have to replace the valve).Edit 2: Bought the heater on Jan 2010 and the heater is still kicking on Feb 2019. I kept thinking it is going to die soon so didn't buy too many replacement magnesium anodes. Now it's time to replace again. Just bought 2 and that should last another 4 years - there's no way this heater going to last that long, right? This water heater might just decide to live long to spite me, LOL!

I had the same problem that many have with a kitchen sink on the other side of the house from the main water heater, (about 35-feet). In winter, it would take up to 30-seconds for truly hot water to be delivered to the sink.First the bad news. When I received my Ariston GL2.5 it was dead as disco. No power, no indicator light, no hot water. I followed the instructions and completely installed the unit before turning the water back on to fill the tank and switch the power on (installation took about 30-minutes). Nothing happened.I checked connections, the outlet, circuit braker, and tightened the connections on the unit itself. Still nothing. I then unplugged and pulled the unit out, drained it, put it on my bench and retightened the connections on the unit once again. I plugged it in on my bench and presto, the indicator light illuminated.Took 10-minutes to reinstall and the unit has worked like a champ ever since, (1-week at time of writing).It was the solution I was looking for. The water coming from the faucet is hot almost immediately. I made only one adjustment to the thermostat because the water was too hot at first.It's true, it its slightly annoying to take off the three covers to adjust the thermostat or switch the unit off. Once it's set, it shouldn't be an issue any longer. I installed a regular wall outlet under my sink with an on/off switch. The GL2.5 shares the circuit with my dishwasher, so no problems with overloads.One thing to keep in mind: This unit and the GL4 and GL6 are designed to service one, (or in the case of a bathroom), two sinks. NOT for use with a shower. My unit services the kitchen sink and the dishwasher.It's advisable to spend the extra few dollars and purchase new, reinforced flexible hoses for the installation. It will make the installation easier.Also, Bosch Customer Service says the heating element of the unit has a 2 to 3 year life under a normal workload. So some maintenance is in your future if you purchase these water heaters.So far, I'm VERY happy with the performance of this unit.

Last time I replaced my water heater I made an expensive mistake switching to another brand, which incidentally was almost 1/3rd more in price. Right from the start I found the other brand to take much longer to heat up and it did not retain heat for long since it had only a thin wrapping of fibreglass insulation vs. the foam insulation of the Ariston. Being that I use this as my sole source of hot water for my kitchen sink and is on a switch to only power it when I want hot water (to reduce my electric usage) it's very much appreciated to be able to turn on the water in the morning and still have warm and sometimes still hot water available (the other brand couldn't even retain heat more than a few hours). It's more than worth the slight extra space that this unit occupies.I also like that this updated model now has an easily accessible temperature control that does not require removing a cover plate (which is now integrated with power switch instead of being two separate items, yet they still retained having an indicator light on this model which can be handy)One IMPORTANT word of advice. Even though this is very small compared to other water heaters, it can put out some serious heat and thus build up a lot of pressure, so make sure there is an expansion tank or accumulator on the water line to accommodate the extra volume of the heated water (unlike air, water does not compress and it will eventually find a way to escape a closed system that can not allow the heated water additional room). In the very least, an RV sized accumulator is warranted, and somewhat larger would be much better, especially if one intends to use the water heater at it's hottest settings or the incoming water is particularly cold.