First, confirm that cole water is reaching the inlse valve. You can do this by turning it off at the water supply, unhooking the host from the valve, and running a little into a bucket or similar container. If you're getting cold water there, replace the valve. You can try to clean out the inlet screen in the valve, but take care not to damage the screen, as this can later be the source of a very costly flood. Part number: AP4026239