20 Most Recent Bosch PowerStar AE125 AE125 Whole House Electric Tankless Water Heater... - Page 2 Questions & Answers

Turn circuit breakers fully off and then back on.Use nose to smell for burning inside main panel.Make sure you are getting 240Volt and not just 120V from one leg of the breaker.Do stress test on breaker panel.http://waterheatertimer.org/Troubleshoot-household-electricity.html#stressLeast expensive solution: Replace tankless computer for $285 buying tank-type electric water heater from local box store.If tankless computer is new, then call installer.If you installed it yourself, call professional installer.http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.htmlGeneh If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Do you have 3-phase water heater? Is this balanced or unbalanced 3-phase unit. Add comment and describe product in detail, including brand since i have some service resources for both types.Or do you have ordinary residential split-phase 240Volt Bosch tankless computer that heats water, and has 2 or 3 separate elements, and a separate circuit breaker supplying power to each element? And testing across both hot leads coming from each breaker yields 238Volt?Copy following link for Bosch tankless manuals, with brief troubleshoot section that does not provide detailed service procedures for repairing tankless computer:http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.html#manualIf this is new water heater, then call installer. If you installed yourself, then remove tankless and return to seller for refund.Tankless computers require certain amount of water flow to activate computer sensors. Turn on Hot tap and listen to pipe to hear if water if flowing through hot pipe. Check for crossover:http://waterheatertimer.org/Crossover.htmlClean water filter usually located just above where cold water connects to unit.Delime tankless ... and use water softener. Tankless cannot be exposed to more than 11 grains hardness in water, or parts will fail within 2-3 years. Simply deliming tankless heat exchanger each year will not maintain full efficiency... although for typical family of 4, tankless comper water heater costs $100 more to operate than tank-type heater according to manufacturer's promo literature and independent studies.Call local technician who specializes in fixing tankless computers. For plumbing problems call local plumber. These are two different things.If tankless computer is older, then cut losses, and buy tank-type electric water heater at Lowes for $285 and make quick changeover and have hot water same day. Sell old tankless on ebay and cheat next guy, or sell at scrapyard for $3 per 100.Geneh If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

My experience in Germany with tankless water heaters was not good; the delivery promised was only vaguely warmed water; they are no replacement for standard devices.
If you can find closet or under-counter (in the kitchen) space you might look into the 20 gallon units made for RVs or small mobile homes/campers. They are not expensive to run and cost well below the ~ $400 US price I saw when looking at the Bosch. If you are worried about the efficiency of them or concerned with the cost of electricity in your area, you could have an electrician install a high-capacity (15-20 Amp) toggle switch (looks like a normal light switch) and manually turn it off completely when it is unused for a longer period of time.
In any case, before you jump on the Bosch bandwagon, check the degree (or lack) of satisfaction from current owners:
http://www.amazon.com/review/product/B0006GVO0S/ref=dp_top_cm_cr_acr_txt?_encoding=UTF8&showViewpoints=1
I wouldn't be encouraged to buy that one.   

You need three #8 wires for AE125. Two #8 wires for AE115.1) Copy following link for wiring information:http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.html2) The AE125 has 3 elements, and requires 3 wires.Each wire is sized #8 copper, and is connected to 40 amp breaker, up to 100 feet. Over 100 feet, use 50 amp breaker and #6 wire. Oversizing breaker and wire is smarted and more efficient than undersizing.3) Often a separate subpanel is installed to provide 3 extra spaces.http://waterheatertimer.org/images/Main-subpanel-Tankless-600.jpg4) Makes sure main breaker panel can accept additional 120 amps of draw without overampping panel ... and starving other appliances of full power.... that will damage appliances, overheat motors, and damage main panel and overheat main breaker. You want to oversize, not undersize electric service when installing tankless electric, which is why I do not recommend tankless electric installation, including issues of costing more to operate, and expensive repairs, and general money risk-nuisance of owning tankless vrs tank-type heater.http://waterheatertimer.org/Troubleshoot-household-electricity.html#stress If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Heating water can peculate chemicals out of water, such as metals and organics. Especially above 138 degrees.Have well water tested.Turn down thermostat temperature.Or reasonably harmless well-water bacteria can react with anode rod, or other reaction in softener, to produce colored water, and smells.Different water can produce different sludges, brown, red, gray, black, yellow.The sludge can also combine with deteriorating pipe flakes to clog water flow.Sludge can accumulate over years in low spots in pipes, or at elbows and constrictions.Have plumber flush pipes.Or run new pipes.Also delime tankless yearly, and flush with white vinegar as shown in product manual, and treat bacteria with H2O2 hydrogen peroxide.http://waterheatertimer.org/pdf/Bosch_Descaling-heat-exchanger.pdf If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

I suppose I would ascertain that the supply voltage is the same there as the outer cutout connectors. If equal, the breaker can be faulty. Worse case the heater has an intermittent short causing overload to trip out.Fix It!

Contact Bosch 800-283-3787, or service technician.http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.htmlProduct has 10 year limited warranty against defects in workmanship, failed parts, failed heat exchanger for original homeowner with receipt. But does not cover neglect, failure to follow maintenance, installation etc. Pg 23 example manualYou generally have to pay for service call to verify installation, then send tankless into factory, or have service technician repair unit, at your expense minus cost of partshttp://waterheatertimer.org/pdf/Bosch-AE115-AE125_manual.pdfTo double check wiring:http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.html If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Product manual shows electro-mechanical thermal cutout page 9 but offers no troubleshoot steps except to say that overheating is cause.http://waterheatertimer.org/pdf/Bosch-AE115-AE125_manual.pdfhttp://www.bosch-climate.us/files/201009211859150.EP-23_Removing_and_replacing_element_assembly.pdfTest elements:Remove both wires off element.Set multimeter to read ohms.Watt and volt rating appear on side of each element.Ohm = Volts squared divided by wattage.For example:Assume 240Volt circuit (240 Volts squared = 57600) Assume 9000 watt element > check side of element for rating.So 57600 divided by 9000 watt element = 6.4 ohmshttp://waterheatertimer.org/images/ohm-reading-for-emements.jpgHave you de-limed this unit?Is there a check valve causing closed system in the plumbing, that might also cause decreased water flow?Are there reduced-flow faucets or clogged aerators?What happens when suspect cut-out element is no longer connected? The unit should continue heating. If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

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

You have a blown element. If you purchased the heater, call Bosch for technical assistance, and the unit should be under warranty. The grey matter your getting is the magnesium that the elements have in them.