Yeah, sediment buildup is sneaky like that. Had a similar issue a couple years back—pressure was all over the map, and showers turned into guessing games (not fun). Turned out our pressure regulator valve was clogged with mineral deposits. Swapped it out for a new one, and things stabilized almost instantly. Now I make a habit of flushing the water heater tank every year to keep sediment at bay...lesson learned the hard way, haha.
Good call on the pressure regulator valve—those things can get seriously gunked up. Couple other things I've run into when troubleshooting pressure weirdness:
- Check your aerators and showerheads too. Mineral deposits love to clog those tiny openings, causing inconsistent flow. Quick soak in vinegar usually clears them out nicely.
- If you're on city water, sometimes the municipal supply fluctuates (especially during peak hours). Installing a pressure gauge at an outdoor spigot can help you track if it's external or internal.
- Expansion tanks can fail or lose pressure over time. Had one that was almost completely waterlogged, causing weird spikes whenever the water heater kicked on. Replacing or recharging it solved the issue immediately.
Also, flushing your heater annually is spot-on advice. I neglected mine for a few years and ended up with a tank full of sediment sludge—lesson learned here too, haha.
