Hi,

I am sorry for a newbie question. I got an Isomac Tea and I am drinking coffee twice per day (during week). What is it normal use, to let the machine turned on, or switch it on/off twice per day?

I would recommend turning it off between uses. It's a good habit and it will also extend the life of your gaskets.

Not to be contrary, but I always preferred to leave my HX on 24/7 so it was always ready.
This also required me to change the group gasket every 4-6 months.

It depends on how close together those two drinks are... If it is one in the early AM and one at dinner, then yes, turn it off. If they are two to four hours apart, more or less, then leave it on. Of course, leaving it on affords the opportunity to increase you coffee consumption!

My rule at home is never leave an appliance on if it can be helped when we are away from the house, particularly one that draws a lot of current or heats.

JonR10 wrote:Not to be contrary, but I always preferred to leave my HX on 24/7 so it was always ready.
This also required me to change the group gasket every 4-6 months.

Yes, it's convenient to be able to just walk up and pull a shot. If changing gaskets and conserving energy aren't issues for you, it probably won't hurt anything. I sometimes leave my Alexia on overnight so that I don't have to wait a half-hour in the morning for it to get up to temp.

It's pretty straight forward.

The Tea takes about 1.5 to 2 hours to get nicely heated up. This is par for the course for machines with heavy groups attached to thermosyphons or huge HXs, since they require not just a hot boiler, but that everything is has heated through and reached thermal equilibrium. If your shots are regularly scheduled and spaced out enough, you can save some energy by turning the machine off between uses and using an appliance timer to restart it.

(... While the machine runs flat out to warm up, total energy use is proportional to the 24/7 average temperature of the machine; so the longer you have it off, the less it uses.)

Some parts on the machine, like seals and gaskets, may last longer if you operate 24/7, since they can be worn by the expansion and contraction of startups and shutdowns. Others, like the electrical parts, where the insulation degrades under high heat, will last longer if you shut down. I don't know how to calculate which operating mode minimizes maintenance costs.

A little math [ for Vibiemme Domobar Super HX ] :

Takes about .25 hours @ 100% to first pStat click plus about .5 hours at 15% until machine is ready to brew.

pStat duty cycle is about 7%, 10 sec on, 140 sec off

(.25 + .5 *.15) / .07 = 4.88 hours

Once the machine is warm, turning it off for less than about 5 hours is false economy. There is some saving for shorter intervals as the boiler water will not have cooled completely.

If at home for several days, the HX with PID and insulated boiler stays on 24/7. It's greener.

Ive always left my machines on 24/7.. Only time they get turned off is when I'll be away for longer then an overnight.

I end up replacing gaskets at the 4-6month interval. Gaskets are cheap.

By design, they're "meant" to be left on. I love never, ever having to wait to make a coffee. I also have almost a full 4cups of hot water on demand at all times. I use the HW for a lot of stuff.. From brewing, for soaking parts in detergent.. even for instant oatmeal and soap. Last week I had this pretty fun headcold and ended up drinking a couple cups of tea, and used the HW for that as well.

I dont really have a "schedule" for drinking coffee like many members do here...I wake up at different times, and have coffee at different times, in different amounts, everyday. A timer wouldn't do me any good(plus, for my machine, it is atrociously overpriced)

Also, timers don't have to be expensive for high amps. Just hook them up to a SSR combined with a butchered USB charger.

cafeIKE wrote:A little math [ for Vibiemme Domobar Super HX ] :

Takes about .25 hours @ 100% to first pStat click plus about .5 hours at 15% until machine is ready to brew.

pStat duty cycle is about 7%, 10 sec on, 140 sec off

(.25 + .5 *.15) / .07 = 4.88 hours

Once the machine is warm, turning it off for less than about 5 hours is false economy. There is some saving for shorter intervals as the boiler water will not have cooled completely.

If at home for several days, the HX with PID and insulated boiler stays on 24/7. It's greener.

This is flat out wrong, a violation of the 1st law of thermodynamics.

Imagine enclosing the machine inside a box that stores heat. The box is at room temperature and it extracts the heat from the machine converting it to stored energy. If the machine is on all the time, it would store the energy of it being at roughly 250F, or 180F above room temperature. If it is on sometimes and off sometimes, it would store less energy. So if leaving it on all the time uses less energy than turning it off, the box would be storing energy that came from nowhere. I know E61 machines are pretty amazing, but they don't do perpetual motion.

A heated environment requires heat in proportion to how much hotter it is than its environment on average. If it is off some of the time, it is cooler on average than if it is on all the time, therefore it needs less heat and uses less energy, startups included.