water heater drain valve plumbing ?? any ideas

I couldn’t figure out what I found attached to this water heater yesterday. The pictures aren’t very good, but the drain valve on the water heater was connected to a pipe that has a pressure valve and an Intermatic timer (like you find on a pool pump motor). The pipe then disappeared into the wall. Any ideas on what that would be?

I also added a last pic of the pex line that was attached on top and the water line for the icemaker to the garage fridge.

Hot-water loop, aka hot-water recirculation system.

The timer is set so that the hot water circulates at specific times during the day, such as 20 or 30 minutes prior to taking your morning shower.

Jeff is right on. The only other time I have seen that is when the water heater was used for heating. In that situation the water heater is designed for heating and often there is a sticker that identifies that.

Why would you need hot water recirculation for a system with a storage tank? I know they install them on tank less water heaters to save water that would be wasted while waiting for the water to warm up. Same idea?

Thanks Jeff, I didn’t think of that. Seems like overkill to me.

Check the fittings.
ZURN have the class action suite going.
That vent stack does not look right. I will look at it later.
Is the home or a room being heated with this recirculation set-up.
Only one hot water tank?

Yes, same idea.