Upgrading to a more efficient water heater can cut household energy bills, but a U.K. homeowner who wanted to "future proof" their hot water system found that replacing an old Fortic tank also meant weighing vastly different installation quotes: one plumber came in at £2,300 ($3,053 USD at the current exchange rate), while another was £850 ($1,128 USD).

Here's what to know

At first, the £850 quote was closer to £500, but the homeowner said it looked different after they rechecked the paperwork. That's because the lower figure only covered labor, installation, parts, and disposal. Accounting for the recommended £350 unit brought the price back up.

Still, the £1,000-plus difference between the two quotes was giving them pause. 

"Does this raise any red flags or should I just take the cheaper?" the homeowner asked in Reddit's r/plumbing. "Both plumbers have been recommended by friends."

Even with that context, commenters said the price difference was large enough to warrant a closer comparison. 

"This exact scenario is why the rule is 'get 3 quotes,'" one advised.

More background

As Reddit users pointed out, given the homeowner's interest in future-proofing, securing the lowest quote wasn't the only consideration. One warned that a "90L cylinder is small for an unvented especially if you plan to change over from an electric shower."

But they also noted that the labor quote wasn't necessarily out of line for the London area. 

One commenter explained that switching from a vented to an unvented cylinder usually involves extra pipework and that "generally 1-2 days should be ok" at around "£400-800 for labour," though a home's specific layout could still affect the final price.

The discussion also turned to cylinder brands and warranty considerations. One commenter identifying themselves as an unvented manufacturer said they would ask for "the spec of the unit," while another who said they worked for a competing manufacturer added of the lower-cost unit, "They are cheap for a reason."

"All I'd say is check out the warranty offered and make sure you are happy with what it does and doesn't cover," they continued. 

What can be done?

Before choosing between the quotes, commenters said to clarify what each plumber is actually providing, how long the installation should take, the cylinder spec, and the warranty information. 

For homeowners weighing their options and looking to future-proof their system, Cala offers another way to think about replacement costs — not just the upfront total but also the long-term cost of running the system. 

Cala's customizable smart heat pump water heaters can help homeowners lower energy bills by heating water only when needed. 

Where can I learn more?

Choosing the right water heater and maintaining it properly can save money over the long term. 

• On Reddit, one homeowner vented that plumbers charged "boatloads" for a heat pump water heater job.

• Households replacing aging tanks found an ultra-efficient upgrade could save as much as $2,100 over time.

• One homeowner was stunned when their new water heater paid off quickly.

• A home expert said basic upkeep can save money by extending a water heater's life.

• In Buffalo, homeowners debated whether an outdated water heater should be replaced before it failed.

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