My rinnai556f heater has no timing buttons to set when it will come on why. it only has an up and down temp button, a child lock button and an energy saver button.

Hi there
Some are different ways. but you can try this.
If you want to activate the child lock function hold down the Temp. and Spin or Rinse buttons at the same time for 3 seconds. Click here to view a simulator showing you how to use the Child Lock. When the child lock is activated only the power button works.
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1. 1 However, Child Lock does not activate until you press Start/Pause.
   
2. 2 Child Lock does not activate until you press Start/Pause. In the holding state, you can open the door or change settings by pressing corresponding buttons. However, once you press Start/Pause to start the washing machine, the Child Lock will be reactivated.
   Can only try
   All the best Clive

I'm wondering if you have activated the child safety lock by mistake? Here's the info from the manual:

If you want to activate or deactivate the Child Lock function, hold

down the Temp. and Rinse buttons at the same time for 3 seconds.

The "Child Lock " indicator will light up when this feature is activated.

When the Child Lock function is activated, only the

Power button works. The Child Lock function remains on even

after the power is turned on and off or after disconnecting and

reconnecting the power cord
I hope that sorts your problem out :-)

It still sounds like the child lock is on since that prevents accidental setting changes on the refrigerator's control panel.The following will NOT work if the child lock function is activated: Freezer Temp Button Fridge Temp Button Power Freeze Button Power Cool Button Ice Type Button Water Button Ice maker Water OR it may be in Cooling Off/Demo Mode. Cooling Off/Demo Mode is a feature used by retailers to display the refrigerator without running the compressor. If your unit is not cooling, and the bars are constantly scrolling up and down the temperature, check your manual for reset advice

Check your user manual, but for my whirlpool it says: If the buttons are inside the fridge, push the FAST COOL and MOISTURE CONTROL buttons at the same time for 3 seconds. Once cooling comes back on, your previous settings will reappear on the display. If the buttons are on the outside of the fridge (as mine are), push the FREEZER TEMP and FRIDGE TEMP buttons at the same time for 3 seconds. Same result as above. Hope that helps.

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" If Child Proof Lock is activated during normal operation, then no functions other than the On/Off switch will be operable until the lock is released"

"If Child Proof Lock is activated while the appliance is OFF, then the complete range of functions will be locked"

Hold the temperature up and temperature down buttons down at the same time for approximately 2 seconds

Link below will take you to a Users amnual if you need one.

http://dl.owneriq.net/e/e0133286-87ca-4872-8218-545badef4052.pdf

Most of the dishwasher in this series have an energy saver dry button. Hold this button in for four seconds and it should unlock the child safety lock. Does not work, try again for 30 seconds. Does not work. We have problem. If your model does not have an energy safer button, then type in the model number and you should be able to find the manual online and open the same to find out how to unlock the child safety lock. If all fails then you need an Electronic control board assembly, about $86 for your model, plus shipping from repair clinic.com. If you are at all handy, this is easy repair. Make sure you turn off the breaker or remove the fuse before you attempt any repairs.

Hold down on the child lock button for 6 seconds.

if your unable to unlock the "childlock" by holding down the button, then it woud seem that theres a problem with the user interface itself

press and hold the child lock button until it beeps...