Heating · Navien Certified · South Shore MA
Boiler Installation & Replacement
A boiler swap is only as good as the piping around it. We size the equipment to a real heat loss calculation, pipe it the way the manufacturer specifies, pull the permit, and hand you a system that runs quietly and efficiently for decades—not one that short cycles from day one.
Before you sign anything: if you may qualify for a 0% Mass Save HEAT Loan, the authorization has to be issued before work begins. Talk to us first—we will tell you what applies to your project. See rebates and incentives.
Choosing the Right Boiler
There is no single best boiler—there is a best boiler for your house, your fuel, your venting situation, and how you make domestic hot water. Here are the options we actually install and who each one suits.
High-efficiency condensing
Mid-90s efficiency, modulating burner, sidewall venting through PVC. The efficiency play, and where the rebates live. Needs annual service and a condensate drain—non-negotiable on these units.
Combi boilers
Heat and endless domestic hot water from one wall-hung unit. We are Navien Certified. Frees up the floor space a tank occupied—good fit for smaller homes and tight basements.
Cast iron
Lower efficiency, but simple, forgiving, and long-lived. Still the right call for some homes—particularly older systems with chimney venting and high-temperature radiation.
Boiler plus indirect tank
Best domestic hot water performance for larger families and homes with multiple baths. A well-insulated indirect tank holds temperature for a long time and recovers fast.
Oil boilers
Still the practical answer where gas is not on the street. If gas is available, run the numbers on converting before you replace oil with oil.
Or skip the boiler entirely
Worth asking. A cold-climate heat pump carries by far the largest Massachusetts incentives and adds air conditioning. We will price both honestly and let you choose.
Sizing, and Why Bigger Is Not Better
The lazy way to size a replacement boiler is to read the plate on the old one and match it. The problem is that the old one was probably oversized too, and if the house has had windows, insulation or air sealing done since, the real heat load is lower than it ever was.
An oversized boiler short cycles. It fires, satisfies quickly, shuts down, and repeats—burning more fuel, wearing out igniters and controls faster, and never reaching the steady-state efficiency printed on the brochure. We run a heat loss calculation on the actual house.
What Installation Day Looks Like
Most straight boiler replacements are a one-day job; combi conversions and jobs involving new venting or gas piping can run into a second day. We pull the permit, protect your floors and stairs, drain and remove the old unit, and haul it away.
The part that separates a good install from a cheap one is the near-boiler piping: correct primary-secondary arrangement where the manufacturer calls for it, proper air elimination, a dirt separator on the return, isolation valves so the next service call does not mean draining the whole system, and clean workmanship you can trace with your eye.
Before we leave, we fire it, run a combustion analysis, purge and balance every zone, set the controls for your system rather than leaving factory defaults, and walk you through operating it. Then we handle the inspection and file your rebate paperwork.
Common Questions
How long will I be without heat?
On a same-day replacement, you have heat again that evening. If we know cold weather is coming and the job will span two days, we plan for temporary heat. Emergency replacements in January get scheduled fast—we keep common sizes available.
Do I need a new chimney liner?
Sometimes. Going from an old oversized unit to a smaller efficient one can leave a chimney oversized for the new appliance, which causes condensation and deterioration. High-efficiency boilers sidestep this by venting out the sidewall. We inspect and tell you before quoting, not after.
Is a combi right for my house?
Often yes, with one caveat: a combi makes hot water on demand, so simultaneous heavy draws—two showers and a dishwasher—need the unit sized for it. In a large home with several baths, a boiler with an indirect tank usually performs better.
What does it cost, and can I finance it?
Too many variables to quote a number honestly on a web page—fuel, venting, hot water setup and the state of the existing piping all move it. We give you real options and pricing at the visit, not a callback days later. See financing to run a monthly payment.
Get a real number.
Options and pricing at the visit—including every rebate you qualify for.