Sink controlling other sinks temp

[TheNewGuy]

Hello!
I am having a small issue, I have three sinks as seen in the picture, when I turn the hot water on for sinks 2 and 3 the water becomes luke warm, i let it run for a good 5 minutes and still no change in the temperature, while 2 and 3 are running I turned on sink 1, after about 10 seconds the temp on sinks 2 and 3 rise to where it's supposed to be, sink 1 temp stays cold though, but if you turn 1 off again 2 and 3 temps drop back down to luke warm. Any help would be great thanks

 

[hj]

Yo are describing a malfunctioning hot water recirculation system, so you may need a competent plumber to diagnose it and make any needed repairs.