Hot water tank - Bock model 51E Was working perfectly until a couple hours ago and then stopped. I have a red light indicator on and I've pressed the red button reset and the motor started up for about 20 secs and then turned off. I tried once more and same thing (won't try again). Is this a problem I can fix on my own or do i need a professional? Thank you. Daniel

There is a flow sensor in the circuit and it is not sensing the lower flow from just the hot water. When you put it on heat though it does.

Its probably time for small claims court and a new company to install good equipment. Have a couple different companies/contractors give an estimate and possibly expert advice/witness you would then be able to use in court so you can get reimbursed from a bad company. Hope it all works out.

Yes you need to delime tankless each year.
http://waterheatertimer.org/pdf/Bosch_Descaling-heat-exchanger.pdf
http://waterheatertimer.org/pdf/Rheem-De-lime-tankless.pdf

Contact Bosch for exact repair information. My records show following number for tankless gas: 800-642-3111
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

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

These anode rods, sometimes made from aluminum, prevent corrosion. The rod emits ions that line the tank and help prevent corrosion. The rod isn't solid magnesium or aluminum; it has an iron core. If your hot water smells of sulfur (rotten eggs), the anode rod has gone bad or there is a presence of hydrogen sulfur gas that is overwhelming the rod. Usually replacing the rod will stop the odor, but sometimes chlorination of the tank is necessary.

I suggest contacting a certified contractor to take care of this for you.

1) Anode rod is located on top of water heater.
It is 1-1/6" hex head.
It might be under a plastic plug, or you might have to take off metal top of tank.
Sometimes you cannot remove anode rod because it is rusted too badly.
I have used impact wrench sometimes and been unable to budge them.

2) Open following links for anode illustrations and resources:
http://waterheatertimer.org/Replace-anode-rod.html
http://www.thisoldhouse.com/toh/video/0,,20047047,00.html

3) Rusty water implies that anode is bad.
But water released by TP valve implies overheating, or bad TP valve.

4) Replace TP valve.
http://waterheatertimer.org/How-to-replace-TP-valve.html

5) Check your burner and combustion parts for orange-or-yellow flame and sooting on parts that implies the water heater needs to be cleaned. You do not want overheated combustion chamber to cause ECO event that might require new gas control thermostat.
Gas should burn with clear blue flame.

6) Overheating tank can also imply that gas control valve thermostat is not working correctly and may soon fail. This would be evidenced if water is very hot and new TP valve doesn't stop hot water release.

7) Take a moment and rate answer:
And 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.

Hello STOP!!!!! don't push the reset button any more.You have a ignition/spark problem.You will load the chamber with oil and will cause major problems when it lites off.Replace the ignition TRANSFORMER on the burner.Avalible for (beckett burner) at home depot/lowes.

Hello DAVID You have a clogged/blocked or restricted chimney!Please shut it off and pull the smokepipe off and locate why there is no draft.All should appear clear and clean.

It sounds to me like you probably have a clogged oil nozzle. Of course I'm am assuming that you bleed all the air out of the oil lines that run both to the hot water tank and the heating appliance. If you have solid flow at the water heater pump, and the unit still does not ignite, it is most likely the nozzle. Hope this helps

Something you can do, following your fathers logic,   is to attach a hose to the drain of the tank and run water from the bottom of the tank into a drain untill all the sediment is removed (Water runs clean). This is normally done once a year as preventive maintenance  on all tank type water heaters. The logic sounds good to me.