Unit shuts off

I just had this exact problem. It kept getting worse until we had no water. Our Rinnai tankless hot water heater started the same way though, with hot water for a few minutes and then would shut off with an error code 10. We just had to shut the hot water off and then back on, wait a minute or so and we had hot water back for a few minutes. Our unit would come on with a loud vibrating noise and remain until it shut off with an error code 10 (air flow fault). The solution was to remove the blower fan and blow out the squirrel cage. Ours had moths in it. We also vacuumed out the fan housing. Be careful to mark any wires you disconnect and take pictures before removal. Our unit is now almost silent when it comes on and supplies endless hot water.

Use a multimeter and monitor the kill switch or whatever switch shuts the unit off normally. It may be failing when warm. Sounds like you covered the basics already.

Check gas control valve.

Good luck,

Marty

This tells me that its either an ignitor or flame sensor. You will need to check to see if the ignitor is working by watching it when the unit comes on and if its not then replace the control board for the ignitor or the ignitor itself. If it is coming on then its the flame sensor. Sounds like the ignitor though. I would check that. These go back on a reg. basis.
Feedback is apprec. Thanks.

could be thermo electronic component normally mounted on the inside of the unit...its to protect against over heating

u could have just replace the main relay and save a lot of money.

Sounds like there is something loose in the line.Like cut off valve,check valve.

Protect mode will kick in whenever a fault is detected.

You get the unit not powering up, and sometimes you hear a clicking noise, that is the protection switch that keeps shutting down the unit.

Causes that can start protect mode are:

Electrostatic harges on internal circuits.
Leave the unit unplugged for power for one hour or so, this will allow discharge.

Bad speaker wiring.
Check speaker wiring, try unplugging and plugging back, or start after removing one speaker at the time.

Internal fault.
Internal fault is the natural cause for protect mode. If all the above did not work, then the problem is a blown component or an internal fault. In this case the unit must be taken apart , tested and repaired by an experienced person.
If the unit is less than one year old, or if you want to get service, call Sony at the phone number listed on the product documentation.

Regards.

The fact that it is putting off that much EXTREME heat tells me that their is a power regulation problem.  I would recommend not using this device at all and disposing of it properly.

It sounds to me like solder overflow (from getting too hot) is shorting out the circut board! Chech the board for short circuts