There is a timer on my water heater. How can I disconnect it? Also, does the timer affect how long my water stays running hot?

Although water heaters are considered to be an appliance, most appliance technicians don't repair them. I would suggest you post your question on the plumbing page where there are very experienced plumbers that can certainly help you. Good luck.

There should be pins, or trippers of some sort that are located at the on and off times, that can be removed to allow the timer to run without being turned on and off.

Be sure the switch that is activated by theses trippers is left on.

The purpose of the timer is to shut the water tank off at times no one is home, or at night while everyone is sleeping, causing power to not be used. Normally the timer is set to go on about a half hour before hot water is needed to allow the tank to heat up.