Have you ever actually measured the temp at the tank versus what comes out at the tap?
You’d be surprised how much heat those attic runs can suck out, even if the insulation “looks okay.” I’ve had tenants swear their water heater was busted, but it turned out to be a drafty attic and some lazy pipe wrapping. Ten years isn’t ancient for a tank, but I’ve seen anode rods go bad and start causing issues before you see rust. If you’ve got a cheap IR thermometer, try checking temps at both ends—sometimes paranoia’s just good troubleshooting.
Had a similar issue last winter—thought the solar tank was underperforming, but it was actually the copper lines in the crawlspace bleeding off heat. Even with insulation, those long runs can be sneaky. I’d double-check for any gaps or crushed spots in the wrap. Sometimes it’s the little stuff that gets you.
Funny you mention the crawlspace lines—I once found a spot where a raccoon had actually chewed through part of the insulation. Ever checked for critter damage or spots where the insulation might’ve gotten wet and lost effectiveness? Sometimes it’s not just gaps, but stuff you’d never expect.
Had a similar issue last winter—except it was squirrels, not raccoons. They chewed right through the foam pipe wrap and made themselves a cozy little nest. Didn’t even realize until I noticed the water wasn’t staying hot as long as it should. Pulled back some insulation and, sure enough, found a mess of shredded stuff and droppings. Fun times.
I’d definitely check for any signs of critters or water damage, especially if your crawlspace is easy to get into (for animals, I mean). Wet insulation is basically useless, and any gaps or holes just make things worse. Sometimes you can’t even see the problem unless you really get in there with a flashlight and poke around.
One thing I learned—don’t trust that insulation is fine just because it “looks okay” from the outside. I thought mine was good until I squeezed it and realized it was soaked underneath from a slow leak. Ended up swapping out a few sections and wrapping the pipes again, this time with some metal mesh around them to keep the furry invaders out. Not exactly pretty, but it’s held up so far.
If you’re still losing heat after fixing obvious gaps, might be worth checking for those less obvious issues. Never thought I’d be fighting wildlife for my hot water, but here we are...
Metal mesh is a solid idea—I did something similar after mice chewed through my insulation last year. Did you check for air leaks around the joints or valves too? Sometimes the smallest gaps can suck out a surprising amount of heat. I found one spot where the insulation looked fine but there was a draft coming in from a cracked vent cover. Plugged that up and saw a noticeable difference. Might be worth double-checking those less obvious spots if you haven’t already.
