Maybe its a problem with the temperature valve in the shower itself and not the water heater. We had the same issue where the water in the shower was scalding hot even if you turned it on just a little bit. Replaced the valve - issue resolved.
(bump) Dealing with a main line leak apparently under the driveway. Plumber is telling me it could cost close to $10k to fix because of old pipes/tree roots in the way. Surely there is a less horrible option! Anyone know someone who can help?
https://www.facebook.com/tmpllc I can recommend Texas Master Plumber -- personal friend -- he'll treat you right. Honest with quality workmanship.
Thank you for the referral. He gave us a quote that was much, much lower than the first guy we talked to and got the leak fixed. Anyone else need plumber service, talk to this guy.
