A Straight Answer from a Guy Who Works on Them Every Day
People ask me all the time:
“How often should I service my tankless water heater?”
And I always give the same answer:
At least once a year — and sooner if you have hard water.
But let’s back up.
Because this isn’t about selling you a service call.
This is about keeping your heater alive — and your showers hot.
Tankless ≠ Maintenance-Free
Some folks think “tankless” means “no work.”
They hear “on-demand” and assume it’s some kind of magic box that never needs attention.
I’ve been called to homes where the unit was installed 7 years ago and never touched since.
You can guess what I found:
- mineral buildup
- clogged filters
- poor flame pattern
- and in one case — a unit completely fried because the heat exchanger was choked with scale
These aren’t rare cases.
They’re what happens when maintenance is skipped.
What Happens During a Service? (A Real One)
When I come out to service a tankless heater, I’m not just wiping dust off the cover.
Here’s what I actually do:
- Flush the system — usually with vinegar or a descaling solution
(Hard water here in Sacramento? This step is non-negotiable.) - Clean the filters — both the water and air filters can get grimy fast
- Check for error codes — even if no one saw them, the unit remembers
- Inspect the burner assembly — looking at flame quality, soot, corrosion
- Test flow rate and temperature consistency — making sure it’s not overheating or short-cycling
- Check the venting — especially on gas units (blockages = danger)
- Reset and recalibrate if needed — small tweaks can fix weird behavior
It takes about an hour. Sometimes more. But it makes a massive difference.
What If You Skip It?
I’ve seen brand-new units ruined in under 3 years.
Why? Because no one flushed them.
Minerals from hard water built up so bad the heat exchanger cracked.
That’s not a repair — that’s a replacement.
And it’s not covered by the warranty if you skipped maintenance.
One guy told me:
“No one said I had to flush it.”
Unfortunately, the manual did.
And now he’s buying a new $1,500 heater.
How You Know It’s Time for a Checkup
Even if your heater seems fine, here are red flags:
- Water takes longer to heat
- Flow rate drops
- It turns on and off repeatedly during use
- You hear strange noises — popping, hissing, rumbling
- Your hot water smells metallic or feels “inconsistent”
If you notice any of that — don’t wait.
It’s not going to fix itself.
At Golden Valley Plumbing, we provide professional tankless water heater maintenance and descaling services throughout Sacramento, Roseville, Rocklin, Elk Grove, Folsom, Citrus Heights, Rancho Cordova, and surrounding areas. Whether it’s annual servicing or emergency repair, our licensed team is ready to help.
