I have this issue in two showers and the kitchen sink. Hot was is fine for a minute, then pressure drops and it goes cold for a few seconds, then back to hot. Happens ever 5 minutes or so and often when no other water is being used. I have well/septic and a tank water heater using gas.

Any ideas?

Is there a recirculating system installed? Back to you, Tom

Is there a recirculating system installed? Back to you, Tom

Thanks for the reply... Too be honest I had to Google it to see what that was. I don't think I do. We bought a new hot water heater 4 years ago and it was for lack of a better term.. a cheaper model. It is a 100 year old farm house and I would guess no.