When you turn on the cold water tap, you expect to get cold water, right? Unfortunately, this is not the case for all of us. Some actually get lukewarm or even hot water from their faucet. Even after letting the water run for a while, the situation might not improve. When this happens to you, it might take some detective work to figure out what the problem is.
It can help to have a thermal imaging tool handy to see where the water changes from cold to hot, but there are a few common culprits. If your water heater is not working correctly, it could leak hot water into your cold water supply. Another possibility is that the water is standing in pipes that are located in a hot area of the house, maybe a crawlspace or garage that isn’t insulated. This is a likely answer if your water is colder on cool days.
It could also be due to a faulty mixer valve in your faucet.