I have the bosch powerstar model #45-550301 electric tankless water heater and it stopped producing hot water

Water leaking into elements. Bad PC board. Undersized breakers. Undersized main panel.
Bosch Powerstar is a computer that happens to heat water.
If your 5-year-old laptop computer was malfunctioning, you would not be surprised.
But for some reason (false marketing by manufacturers?), folks believe a tankless computer is going to last 20 years.
Moreover folks also believe tankless will provide endless hot water while saving money.
The whole idea of tankless saving money is a load of sales-BS that defies physics and common sense.
There are no service manuals... except bosch website has troubleshoot section in product manual.
Call a bosch-qualified service tech.
Go to Lowes and buy ordinary tank heater, and fix your heater today for only $250.
Tank-type electric water heater can be easily repaired and maintained by homeowner to last forever... that is a fact
http://waterheatertimer.org/How-to-maintain-water-heater.html

http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.html

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Call Bosch. And exercise your 10 year parts warranty rights.
Copy following link for Bosch power star manuals:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html#Ariston
Check circuit breakers, fully off and then fully back on. Test if voltage is at least 80% rating plate on unit. Check that temperature dial is set correctly. Call for service again.
Don't install tankless computer that heats water. You cannot fix this computer yourself, and they are problematic for owners.
Go to Lowes right now, spend $285 and buy tank-type electric water heater, roll it into your house, and save money, since the electric tankless computer heater costs average $100 more per year to operate than tank-type heater for average family of 4.
Tank type heater can be repaired by homeowner same day for $25 using off-the-shelf parts from hardware store. And that empowers the regular guy, and gets you off the junk tankless treadmill.
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

This is a "point of service" tankless water heater that was manufactured by BOSCH. BOSCH is now Bosch-Climate.us. Technical support is available at 866-330-2729. P.S. check this site: http://tanklesswaterheaterz.com/bosch-ae-9-5-powerstar-1-5-gpm-point-of-use-indoor-tankless-electric-water-heater-reviews/

Question posted under Bosch tankless.
Question says 'tank'
Brand, model, and type heater unknown.
Elements mean electric.
'Thermal cutout pops when taking shower produces cold water' indicates tankless, since tank-type would maintain some hot water.
No error code might indicate tank-type.
Add a comment with type, brand and model number of heater for possible assistance.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

There are a lot of other things that eat electricity. Like space heater and using ovens for heat. Heat pump.Central heat fan running all the time. House lights left on. Outside flood lights. Clothes washer using HOT water. Look around real good. It all adds up. Also the power co. may be charging more for "fuel" costs surcharges. Here in GA I'm paying a bit more now to pay for a nuclear power plant.

Open following link for Bosch tankless troubleshooting resources, including Bosch contact information, typical manuals, error codes, tech support, parts, fuel-saver calculator, water heater forum, fixya links, disclaimers, and for finding service technician.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Add a comment with your experience so others with same-similar problem can benefit.

Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

try bleeding that section of pipe. or the whole system if not.

have a life source pedometer h215 don't know how to set my stride?

That is a single phase hot water heater. Hope this helps