**Update** This problem has been resolved.

Hello plumbing experts :)

I see that someone else has recently asked a similar question to mine but I'm not sure that the same advice would apply so I'll post my question too in hopes that someone can help.

My shower's (no tub) water temperature is only getting up to lukewarm at best & it seems to be getting gradually worse. In the kitchen and bathroom sinks, the water becomes extremely hot. Before I got this house, there was a really botched job done on the plumbing. Just this past week I had to have a certified plumber come out and replace everything underneath the house because it was all done wrong. I asked him about this hot water issue and he wasn't 100% sure what it could be. The shower head & handle are the Delta brand. The plumber informed me that sometimes hot water can be blocked by faulty equipment, is that true? He took the shower head off and cleaned it but that did not solve the problem. The handle turns all the way to the left for hot and to the right for cold. Before the shower was installed, a hole was cut in the wall for the pipes and the shower is covering that wall so I'm hoping the problem isn't behind there. Anyone have thoughts on what the problem could be? If you need more details, please don't hesitate to ask. Thanks in advance for your replies!

Have you shut the water off and opened up the Delta shower valve to check the hot water inlet for a clog? Take the valve apart down past the seats and springs. Now turn the hot water on to flush out the valve body and the hot water supply. You should have a strong stream of hot water when you do this. Reassemble and test. More hot water now?

Hi speedball,

Thanks so much for taking the time to reply. Before I noticed that you had responded, I worked on my shower some this morning. Good news: I fixed it!

I got curious & took the whole works apart. When I disassembled the single handle control, I noticed that it had a plastic piece which controlled the temperature. It was set dead in the middle, hence the lukewarm water. I set it to the hottest setting available, reassembled, and the hot water temperature is now perfect. :) I think the problem seemed to be getting worse because it's getting colder outside and that cool air was lowering the temperature a little in the pipes before it reached the shower. I could be wrong but that's my guess. I'm just thankful it wasn't something a lot more serious.

Thanks again for replying. I would have tried your advice next. :)