I get where you’re coming from, but I wouldn’t write off insulation so quickly. —sure, if there’s a bigger issue.
Totally agree that insulation isn't just "wrapping up problems." In my place, I saw a 3–4°C difference at the tap after insulating just the exposed runs. It’s not magic, but it’s noticeable, especially during cold snaps.
A couple more things to consider:
- Pipe runs: Are any of the hot water lines running outside or through unheated spaces? Even a meter or two of uninsulated pipe can bleed a surprising amount of heat.
- Recirc loops: If you have a circulation pump, timers/settings can make a big difference. Sometimes the default timer is way off from when people actually need hot water.
- Storage tank: Is the tank itself well-insulated? Sometimes folks focus on the pipes and forget the tank jacket, which makes a bigger difference than most expect.
You mentioned valves—what about mixing valves? If yours is set too low, you might be getting lukewarm water even if there’s plenty of hot in the tank. Ever checked that?
Just curious, how long does it take for hot water to reach your tap from the heater? That can tell you a lot about where heat’s being lost.
Mixing valves are a sneaky culprit—seen plenty set too low, just like you mentioned. People chase insulation or tank upgrades and overlook that little adjustment. Can make all the difference between “meh” and actually hot water at the tap.
Sometimes folks focus on the pipes and forget the tank jacket, which makes a bigger difference than most expect.
Absolutely. I’ve been called out to jobs where the pipes are wrapped up tight but the tank’s sitting there bare, losing heat like crazy. It’s not glamorous, but it works.
If you’re seeing a few degrees’ improvement from pipe insulation, you’re already ahead of most. That lag getting hot water to the tap? Usually tells you exactly where the problem is—either distance, uninsulated runs, or the timer’s off on your recirc loop. I’d say you’re looking at it the right way. Sometimes it’s not one big fix, just a bunch of small tweaks that add up. Don’t get discouraged if it takes a bit of trial and error.
Mixing valves really do get overlooked—seen folks crank up the tank temp thinking that'll fix it, but if the valve's set too low, you’re just wasting energy. I’d also double-check for any sneaky cold water crossover, especially if you’ve got older fixtures. Had a job last winter where a single faulty check valve was cooling down half the hot runs... drove me nuts till I found it. Sometimes it’s not even insulation or settings, just a tiny part acting up. Those little details add up fast.
Sometimes it’s not even insulation or settings, just a tiny part acting up.
Not sure I’d agree that insulation’s not a big deal—especially with solar. Even if your mixing valve’s dialed in, if the pipes are losing heat between the tank and the tap, you’re still getting lukewarm water. I’ve seen people overlook attic runs or crawlspace lines and it just bleeds off all that stored heat, no matter how perfect the valves are. Sometimes it really is just a roll of foam away from fixing the issue.
Insulation gets way less credit than it deserves—kind of like the bass player in a band. You don’t notice it until it’s missing, and then everything just sounds... off. I’ve lost count of how many times I’ve crawled under a house or poked around in an attic and found pipes just bare as the day they were installed, radiating away all that precious hot water like they’re trying to warm up the squirrels.
I get what you’re saying about tiny parts acting up—mixing valves, check valves, even a stuck air vent can throw things off. But if you’ve got a solar setup, you’re already fighting an uphill battle against heat loss, especially first thing in the morning or after a cloudy day. Doesn’t matter how well your system’s tuned if the heat’s leaking out before it even hits your shower.
One time I helped a neighbor who swore his solar heater was “junk” because he’d only get a quick burst of hot water, then it’d go cold. Turns out, his hot line ran through about 30 feet of uninsulated crawlspace. Wrapped it up with some cheap foam sleeves and suddenly he’s singing the praises of solar like he invented it.
It’s not glamorous work, and nobody’s ever bragged about their pipe insulation at a barbecue, but it makes a world of difference. If you’ve checked all the gadgets and the water’s still lukewarm, grab a flashlight and see if your pipes are shivering in the attic or crawlspace. Sometimes it really is that simple.
