Thermostatic valves definitely help, but from what I've seen, they're more of a band-aid than a real fix if your plumbing's got deeper issues. I mean, yeah, they'll smooth out minor fluctuations, but if your pipes are undersized or your water pressure is all over the place, you're still gonna feel that temp drop.
A lot of older houses I've worked on had galvanized pipes or weird DIY plumbing jobs from previous owners. Even with a good thermostatic valve, the shower would still go chilly when someone flushed or ran the dishwasher. In those cases, the valve's basically fighting a losing battle. It's like trying to drive steady on a road full of potholes—sure, good shocks help, but you're still gonna feel the bumps.
If you're serious about fixing the issue, I'd suggest looking at the supply lines themselves. Sometimes just upgrading to larger diameter pipes or replacing old corroded lines can make a huge difference. I've seen homeowners spend money on fancy valves only to realize later that the real problem was their plumbing layout or pipe sizing.
Not knocking thermostatic valves—they're solid and reliable—but they're not magic. They can't overcome fundamental plumbing issues. Sometimes it's worth stepping back and looking at the bigger picture before investing in a valve upgrade. Just something to think about...
"Even with a good thermostatic valve, the shower would still go chilly when someone flushed or ran the dishwasher."
Exactly my experience. Had a client last year with a similar issue—old house, galvanized pipes, DIY plumbing mess from previous owners. We tried a thermostatic valve first, and yeah, it helped a bit...but didn't really solve it. Ended up replacing some undersized supply lines and that finally did the trick. Ever checked your pipe sizing or pressure balance? Might be worth looking into before throwing money at valves.
"Ended up replacing some undersized supply lines and that finally did the trick."
Interesting point about pipe sizing. Hadn't really considered that angle before—I always assumed it was purely a valve issue. Our house is older too, and we've been dealing with similar temp swings. Do you think upgrading just the main supply line would help, or would we need to redo all the branch lines as well? Trying to keep costs reasonable, but also tired of surprise cold showers...
We had a similar issue at our place—older home, undersized pipes.
Honestly, just upgrading the main line made a noticeable difference for us. Might be worth trying before redoing everything..."Ended up replacing some undersized supply lines and that finally did the trick."
Interesting point about upgrading the main line—I've seen that help in some cases too, especially if the main supply was really outdated or corroded. But I'm curious, did you notice any pressure issues elsewhere in the house after upgrading just the main line? Sometimes fixing one bottleneck can reveal another hidden issue further down the line... plumbing can be tricky like that.
