Said It Here

Is an improper water heater exhaust pipe slope dangerous?

An incorrect exhaust pipe grade creates a serious risk of fire or carbon monoxide leaks. This makes the system unsafe to operate and requires immediate expert attention to correct.

Overview
People affected10 accounts across 2 forums
Workarounds found12 items attempted
Community agreement73 total upvotes

What the numbers show

Counted from the threads quoted below. How we count

  • The most recent one is from October 2026.
  • This comes up 14.2× more often in r/Plumbing than across the site as a whole.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

12 items+ Contribute

Found another way around this?

Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.

  1. 1
    getting a shorter water heater
    Did this help you?
  2. 2
    finding a higher spot on the chimney
    Did this help you?
  3. 3
    Turning off the heater
    Did this help you?
  4. 4
    Removing damaged duct tape and cutting away compromised drywall
    Did this help you?
  5. 5
    Hiring an HVAC contractor to inspect and replace the venting system
    Did this help you?
  6. 6
    Calling a professional plumber to fix the installation
    Did this help you?
  7. 7
    Checking outside the house for existing discharge lines
    Did this help you?
  8. 8
    Turned off the water heater and went without hot water
    Did this help you?
  9. 9
    Looking up code compliance and B-vent kits
    Did this help you?
  10. 10
    shutting off the gas valve or turning it to pilot mode
    Did this help you?
  11. 11
    aligning the vent pipe
    Did this help you?
  12. 12
    purchasing carbon monoxide detectors
    Did this help you?
Tried another approach not listed above?+ Share your workaround ↑

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/Plumbing7 people · September 2026 – October 2026

“I don't think this safety release is hooked up correctly. It runs right back to the service line.”source ↗

“Should I disconnect plug it and let it hang to garage floor?”source ↗

Melodic_Lawyer9634 · r/Plumbing · 19 upvotes

“Shut the gas *off* to the water heater until the exhaust pipe could be installed correctly. You’re talking carbon monoxide spillage.”source ↗

Negative-Instance889 · r/Plumbing · 17 upvotes

“Dude you have that as a big problem and the venting is non existent? Call a pro to fix these things”source ↗

Dillcap · r/Plumbing · 10 upvotes

“Turn that shit off before your family dies”source ↗

Low-Organization2969 · r/Plumbing · 2 upvotes

“That is tapped into the cold water supply line.”source ↗

IVlassacre · r/Plumbing · 1 upvotes

“Bro how do I turn it off”source ↗

Canaduk · r/Plumbing · 1 upvotes

“Don’t get me wrong, the grade was bad before too, but I think this is worse.”source ↗

NotPenguin_124 · r/Plumbing
r/hvacadvice3 people · September 2026

“I turned off the water heater and we’ve been without hot water all weekend. Pregnant wife isn’t happy.”source ↗

verysmartfellow · r/hvacadvice · 13 upvotes

“When it comes to things that have a high chance to burn down my house I go to the experts. You were correct in turning everything off. That seem super dangerous not only as a fire risk but CO as well.”source ↗

turbo2thousand406 · r/hvacadvice · 6 upvotes

“Trying to address this janky DIwhy job from the previous owner.”source ↗

“It seems dangerous to me and is getting out of DIY territory and I would like some advice from experts.”source ↗

gumbykook · r/hvacadvice · 4 upvotes

Where this came up

r/hvacadvicer/Plumbinggas applianceshome maintenancehvacinstallationplumbingsafetysafety hazardsafety hazardswater heater

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