A new water heater is supposed to solve problems, not create new ones. But for one homeowner, a replacement job instead led to a trip online for a second opinion after several details in the installation raised concerns.

Here's what to know

Following the swap from an older natural-gas tankless heater to a Rinnai RE180, the homeowner shared annotated photos on Reddit and asked other users to look over the installation.

"Please point anything out not to code or not aligned with manufacturer recommendations. I circled concerns of mine in red," the homeowner wrote.

Users pointed to several parts of the setup that they thought warranted a closer look.

One asked, "No issue with the non UV rated pex directly off the tank?" Another wrote, "Biggest issue I see is the use of CPVC pipes (but that seems to have been there all the time, not part of new install)."

For homeowners who can electrify during a replacement, a heat pump water heater may also be worth comparing before signing off on a new gas unit. Depending on the home and the equipment being replaced, that switch can lower utility bills.

More background

Tankless water heaters can reduce wasted energy compared with conventional storage tanks because they heat water on demand, but proper installation is still critical.

PEX that is not rated for UV exposure can degrade in direct sunlight, while CPVC is often criticized for becoming brittle over time.

The placement of the unit also drew scrutiny from one commenter, who wrote, "Where do you live bc in Texas all heaters are inside or covered?" The OP later clarified they live in Florida and that the tank and piping are in direct sunlight for about eight hours each day, which led some commenters to express concern about how some of the materials would fare in that radiation over time. 

Gaps where pipes pass through stucco can allow in moisture, pests, and air leaks, potentially leading to additional repair costs later.

What can be done?

If a new water heater installation looks questionable, the next best step is often to ask the contractor for permit information, installation manual references, and a written explanation of the materials used.

Homeowners can also request a municipal inspection or seek a second opinion from another licensed plumber familiar with the brand.

If you are replacing a water heater anyway, it may also be smart to compare electric heat pump models with gas or standard electric options. Companies such as Cala are trying to make that choice more appealing for consumers focused on both comfort and monthly savings.

Its customizable smart heat pump water heaters help homeowners reduce their energy bills by heating water only when needed. Cala systems are designed to store hot water intelligently, helping households avoid unnecessary energy use and better manage demand throughout the day. For shoppers looking for a longer-term bill-cutting upgrade, Cala offers another example of how water heating technology is changing.

"Have some concerns with the recent new install, but don't know enough about plumbing," the original poster wrote.

A commenter suggested a straightforward way to address one part of the job: "OP can easily caulk or seal the holes in the stucco."

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