A Cala heat pump water heater, installed, from about $5,000 after $1,550 in rebates

Two of the three parts apply to every homeowner: the $300 NEHPA rebate and the $500 SumZero Fall promo, whoever supplies your power.

The $750 Mass Save® rebate works differently. It requires a participating utility, so it depends on who your electric or gas provider is.

We check which parts you qualify for at the free walkthrough, and the result is already in the fixed price we give you — before anything is ordered. If a part does not apply to you, you know before you commit, not after.

The Cala is 77 inches tall and 34 inches wide, and it holds 65 gallons. Because it is a heat pump, it works by drawing heat from the air around it — so it needs some air around it to do its job.

A tight or finished space is usually still fine. We measure the clearances at the free walkthrough, and if it will not fit, you hear that from us before you have spent anything.

It runs on a variable-speed compressor, so most of the time it is working gently rather than at full tilt.

A side effect worth knowing: as it heats your water, it dries and cools the air around it. In a damp basement, most people find that is a bonus.

If your tank sits somewhere sound matters — next to a bedroom or a home office — tell us at the walkthrough and we will talk through where the unit goes.

Hours, not days. A standard replacement is a single visit: the old tank comes out, the Cala goes in, we commission it, and we walk you through the app before we leave.

Anything that is not standard — moving the unit or extra electrical work — is flagged at the walkthrough, so you know what install day looks like before it arrives.

$5,000 covers a standard swap: an existing water heater in an accessible basement or utility area, with electrical and plumbing within standard proximity. A few things can change that:

• Moving the unit to a different spot
• Additional electrical work
• A new condensate line
• Limited access to the space

If any of those apply, you get the fixed number in writing before anything is scheduled — and the $1,550 rebate applies either way.

Yes. 0% financing is available through the Mass Save® HEAT Loan, so you can spread the cost rather than paying it all up front.

We walk you through the financing options at the walkthrough, alongside your fixed price.

Two layers of cover:

• 10-year parts warranty, transferable — if you sell the house, the cover goes with it
• 3-year labor warranty from SumZero on the installation

With your permission, we also monitor the unit remotely, so we can often spot a problem before you notice one.

We cover MetroWest and Greater Boston from our shop in Holliston — Holliston, Hopkinton, Ashland, Framingham and 20 more towns around them.

Put your ZIP code in when you book, or call (508) 306-1415. If your address is outside the area, you will know on the first call rather than after a site visit.

Four steps, and nothing is ordered until the third one:

• We call within one business day to set a time.
• Free walkthrough: we look at your space, your electrical panel and how your household uses hot water.
• You get a fixed price in writing, with the rebate already applied.
• If you say yes, we schedule the install — one visit for a standard swap.

There is no obligation at any point before you sign.