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

It should be producing hot water at the temp it was set at such as 120-140 degrees. If it is exceeding this one of the safety devices maybe disconnecting it. Thermal control might need some servicing. See what temp it's set at then put a thermometer on a near water outlet to see what's going on. Good luck.

I just tried to replace one of the o-rings on an AE125. The old original one came out distorted do to the fact that there's no groove to hold the o-ring in a uniform position. Even though I was careful and evenly tightened the cap screws, the new o-ring started leaking an hour after I had left the job. My opinion is the mounting of the metal lid to the plastic tank is a bad design. Good luck on your repairs.

It sounds like you have a copper canister unit. Ohm out the elements in that one canister. the directions are on the websight for bosch, or I can walk you through it. But you will need a digital multimeter to do this. If you have a blown element in that one canister, then the tco will not reset.

Replace heater? Do not install tankless. Call for service? Manual does not show troubleshoot or repairs Bosch site does not show the AE125 series water heater any longer http://waterheatertimer.org/pdf/Bosch-AE115-AE125_manual.pdf Gene If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

http://waterheatertimer.org/pdf/Bosch-AE115-AE125_manual.pdf Bottom page 10 troubleshoot Add tempering tank to pre-heat cold incoming water http://waterheatertimer.org/Tempering-tank.html Call service technician Delime heat exchanger. http://waterheatertimer.org/How-to-delime-tankless-water-heater.html Replace with tank type? http://waterheatertimer.org/How-to-install-electric-water-heater.html Gene If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Light flashing while water is flowing means you have a bad control board. Needs to be replaced. They can be purchased online

Control unit or flow transducer. If the transducer(impeller in the clear tube) is spinning freely with waterflow, then the circuit board needs to be replaced.

there are no valves in the unit. You can only regulate waterflow through this machine with self-supplied ball/gate valves

Flashing light means bad control unit..or your flow is too low. If you have a couple fixtures on, and its still blinking, the board needs to be replaced.

Hey Andy. Do you have your owners manual? There should be a section near the back that will break down the diagnostic code the flashing light is giving you. If not remove the front cover and look inside should be a wiring diagram and light legend.

Turn of leave for 2 minits then try again