Upgrading to a heat pump water heater can potentially save homeowners hundreds of dollars a year on energy bills. That kind of replacement entered the conversation after a Southern California family discovered its garage water heater was sinking into a rotting stand that had also been soaked by an AC drain leak.

Here's what to know

According to the homeowners' child, both the water heater and AC equipment were installed on a hollow box in the garage, and repeated overflow from the secondary condensate line had already created a "pretty big hole" near the air conditioning unit.

They turned to Reddit for advice. "The water heater seems to be too heavy and sinking and cracking the foundation it's on," they said, while asking both who should handle the repair and how quickly it needed attention.

A respondent said, "This is something that just about any local HVAC or plumbing company could assist you with," and said the tank would likely need to be drained, disconnected, and removed so the platform beneath it could be examined.

Across the discussion, people suggested starting with whichever local professional could legally move the heater and help rebuild the base — whether that meant a plumber, HVAC company, general contractor, or handyman. They said the support under the tank needed to be evaluated before the sagging got worse.

More background

Users noted that the raised platform itself wasn't that unusual for a garage setup. In many homes, water heaters and furnaces are set up above floor level because gasoline vapors can collect low to the ground, and raising the appliances helps reduce the risk that the fumes will be set on fire.

What alarmed people here was the apparent deterioration of the surface. The original poster described the box as "very very soft" and said holes formed when a fingertip brushed across it, a sign that the material may have been weakening for quite a while.

One user also criticized the drainage arrangement, saying the secondary AC line "was designed to let water out onto the floor, which is not a good idea" and suggesting there may have been a nearby drain pipe that should have been used instead of letting overflow spill onto the platform.

That kind of moisture damage can weaken OSB, drywall, or plywood over time without drawing much notice. 

One user said, "Waiting for it to actually cave in is far more expensive."

What can be done?

Users said the first practical step is to have the heater shut off, disconnected, and moved so the stand can be opened up. Once that happens, a contractor or handyman could determine whether the portion beneath the water heater still has adequate 2x4 or 4x4 support.

What happens next depends on the condition of the framing. If the structure underneath is still sound, one user said a new, thicker plywood surface might be enough to level the area, but if the wood below has decayed, the platform may need a more extensive rebuild before the tank is put back.

For future prevention, users mentioned raising the drain pan on bricks or rubber feet to improve airflow and installing a float switch that shuts the HVAC system off if the condensate line backs up. 

If a replacement is on the table, Cala's customizable smart heat pump water heaters can help homeowners decrease their energy bills by heating water exactly when it is needed. The company's smart heat pump water heaters offer a lower-energy alternative to a standard electric tank, and comparing options from Cala could make sense once the damaged stand is opened up and assessed.

After reading through the replies, the OP said, "strangers telling me it's not a HUGE deal is helping me feel like I can take time to call around/hire/plan and schedule for them ... and they won't get scammed out of their mind by trying to rush everything or pay the first guy that promises to do everything right away himself."

Where can I learn more?

Each case looks a little different, but hidden leaks, aging tanks, and awkward equipment placement are common threads. These articles cover water heater failures, garage and crawlspace leaks, maintenance questions, and unusual setups involving AC equipment.

• While visiting Texas, a Florida homeowner saw water heaters and AC units in the attic and feared damage.

• In Colorado, a homeowner's leaking water heater failed, and a crawlspace move could reclaim a closet.

• In one garage, a $7 drain valve solved a leak that looked catastrophic.

• A home expert said critical water heater tips could prevent breakdowns and cut repair bills.

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