Clement Boston Heat Pumps installs ducted heat pumps across Boston and the towns within 20 miles. This guide is the long version of a first-visit conversation: what a heat pump is, whether it will heat your house, which job yours is, what it costs and how to know it was installed right.
How a heat pump heats and cools
A heat pump is an air conditioner that runs in both directions. In summer it moves heat out of the house; in winter a reversing valve flips the flow and it moves heat in.
Where the heat comes from in winter
There’s heat to move even on a cold night. The outdoor coil runs colder than the air around it, so heat flows into the refrigerant, and the compressor raises it to a temperature that can warm the house.
Because it moves heat instead of making it, a heat pump delivers two to three units of heat per unit of electricity on a typical winter day. Electric baseboard delivers one.
Ducted and ductless
A ducted heat pump puts the air handler in a basement, attic or closet and sends air through registers, the way a furnace does. That’s the work we do. A ductless mini split mounts a head on each room’s wall instead.
Will it heat a Boston house in January?
Yes, if it’s a cold-climate unit sized for your house. Cold-climate heat pumps keep producing heat well below zero, and Mass Save requires equipment on the ENERGY STAR cold-climate list, which is tested to 5°F.
Sizing to the design night
Boston sizes heating to a design temperature of 7°F at Logan. Inland is colder: Bedford’s Hanscom Field logs about five nights a year at or below zero, against fewer than one at Logan. We size to the colder figure in Lexington, Belmont, Waltham, Woburn and past Route 128.
What the winter feels like
A unit sized for that night runs long, quiet cycles most of the winter and works hard only in the coldest stretches. Backup heat strips cover those hours and defrost, and good controls keep them off otherwise. See do heat pumps work in Massachusetts.
Start with what heats your house now
The system you have today decides the kind of job, the rebate path and the price range.
| What you have now | The usual plan | Where to read more |
|---|---|---|
| Oil furnace with ducts | Heat pump on the existing ducts, burner out, tank removed | Oil to heat pump conversion |
| Gas furnace and central AC | Heat pump replaces the AC; the furnace goes or stays as backup | Gas furnace to heat pump |
| Boiler and radiators | New ducts from attic and basement air handlers, or a small-duct system | Boiler and radiator homes |
| Electric baseboard | Ducts in the attic or crawlspace; the clearest savings of any conversion | Electric baseboard to heat pump |
| Central AC that just failed | A heat pump in its place, on the same ducts | Replace central AC with a heat pump |
| An old heat pump | Replacement, resized from a new load calculation | Heat pump replacement |
Statewide, a little over half of homes heat with gas and about one in five with oil. In Boston, oil heats about 7% of homes; in Lexington, close to a third.
About a quarter of Massachusetts homes heat with a boiler and radiators, which is why “no ducts” is one of the most common questions we get.
Whole-home or keep a backup?
A whole-home system carries all the heating with the old equipment removed. Dual fuel keeps a furnace for the coldest hours. A partial system heats part of the house.
How Mass Save treats each
Whole-home earns the largest per-ton rebate. Dual fuel with integrated controls earns the partial-home rebate. Replacing an existing heat pump earns the basic rebate.
Town rules
In Cambridge, Arlington, Brookline, Newton and Lexington, a major renovation can’t add new fossil-fuel equipment, which rules out a new furnace as backup for that work.
Sizing from the house, not the old unit
A ton is 12,000 BTU an hour. The right number comes from a room-by-room load calculation using the ACCA Manual J method, never from the old furnace or AC.
The calculation counts wall and window areas, insulation, air leakage, orientation and the design temperature. Oversized equipment short-cycles and leaves summer air clammy; undersized equipment runs on backup heat in January.
Seal first, then size
Air sealing and insulation before sizing can drop the load enough to shrink the system, and Mass Save pays a sizing bonus for systems sized to the home’s total heating need. See how a heat pump is sized.
Ducts: reuse, fix or add
A heat pump moves more air at a lower supply temperature than a furnace, so we measure the ducts before choosing equipment.
Reusing furnace ducts
Furnace ducts often need a bigger return, sealed seams or a few resized branches. A system starved of airflow runs loud, freezes its coil in summer and leans on backup heat in winter. See ductwork testing and repair.
Adding ducts where there are none
Ducts come from the top and the bottom: an attic air handler for the upper floor, a basement unit for the first, and stacked closets carrying trunks. Small-duct systems run 2-inch tubes where a standard duct won’t fit.
The electrical service
A whole-home heat pump with backup strips draws real current, and many older houses still have 100-amp service.
Some carry a heat pump fine with smaller backup heat or a load-managed setup. Others need 200 amps: a new panel and meter socket, and a day with Eversource or National Grid after the wiring inspection. Boston’s permit for a service upgrade is $20 plus $0.25 per amp. See electrical upgrades.
Where the outdoor unit goes
Snow, noise, rules and service access decide it.
- Snow: a stand above drifting snow, out from under roof drip lines, with room for defrost meltwater to drain.
- Noise: Boston limits nighttime noise to 50 dBA at the lot line, and Cambridge’s guidance sets 50 dB(A) at night at the neighbor’s line.
- Rules: in Back Bay, Beacon Hill and the South End, historic district rules limit what the street can see.
- Salt: near the harbor, salt exposure changes the unit choice and the maintenance.
See snow stands and outdoor unit placement.
Controls, aux heat and the thermostat
The thermostat has to know it’s running a heat pump: stage the compressor, hold back the backup strips and, on dual fuel, hand off to the furnace at the right temperature.
We set a lockout so the strips stay off above a chosen outdoor temperature and record it at startup. A heat pump running aux heat on a mild day is set up wrong. See heat pump aux heat and thermostats.
Old houses, three-deckers and condos
Boston’s housing is old, and the work bends around it rather than ruling it out.
- Older houses: balloon framing, plaster and lath, and little insulation change where ducts go. See heat pumps in older houses.
- Three-deckers: usually a system per floor, each sized for its unit, with outdoor units on the back porches or the flat roof. Mass Save counts rebates per meter. See three-deckers.
- Condos: the board and the master deed decide where outdoor units sit. See condo replacement.
Running cost against oil and gas
Per million BTU delivered, a cold-climate heat pump on Eversource’s or National Grid’s winter heat pump rate costs less than heating oil or propane, and more than natural gas.
That order holds at average prices; your bills depend on your house and rate. The seasonal heat pump rate lowers part of the delivery charge from November through April on all the electricity the house uses.
Getting the heat pump rate
Homes that received a Mass Save heat pump rebate are usually enrolled automatically; others ask the utility to switch them. Compare heat pumps and oil and heat pumps and gas.
What it costs
Our typical range for a whole-home system on ducts we can reuse is $15,000 to $28,000 and up before rebates.
| Job | Our typical range |
|---|---|
| Whole-home, ducts reused | $15,000 to $28,000 and up |
| With new ductwork or a small-duct system | $20,000 to $40,000 and up |
| Replacing an existing heat pump | $12,000 to $24,000 |
| Electrical service upgrade | $3,000 to $6,500 |
| Basement oil tank removal | $600 to $1,500 |
The cost guide breaks down what moves each number.
Rebates, loans and the light plant towns
Mass Save pays its whole-home rebate per ton for qualifying equipment installed by a participating contractor in its Heat Pump Installer Network, and offers 0% HEAT Loan financing up to $25,000.
The amounts
The whole-home rebate is $2,650 a ton up to $8,500 for systems installed through 2026, and $2,350 a ton up to $7,500 from January 1, 2027. The house needs proof of weatherization and the old system removed or disconnected.
Light plant towns
Towns with their own electric light plant run their own programs for oil, propane and electric-heat switches: Belmont, Reading and its neighbors, Braintree, Wellesley, Concord, Hingham, Peabody, Wakefield and others. The federal heat pump tax credit ended for systems placed in service after December 31, 2025. See Mass Save heat pump rebates.
Taking the old system out
Whole-home means the old system goes, removed or disconnected.
A gas furnace or boiler comes out and the line is capped by a licensed gas fitter. An oil burner comes out, the fuel line is capped, and the tank can be pumped and removed; in Boston that takes a Fire Department permit. See oil tank removal.
How the install runs, and how it’s checked
After permits, most ducted installs take two to five working days on site: removal and the outdoor stand, then the air handler, ducts and line set, then wiring.
The checks that decide the next 15 years
- Line set pressure-tested with nitrogen
- A deep vacuum below 500 microns
- Refrigerant charge weighed in for the actual line length
- Airflow and static pressure measured
- Controls set and the backup heat lockout recorded
Ask any installer whether they do each of those and whether you get the readings. See the installation process and questions to ask an installer.
Living with it
A ducted heat pump runs all year, so it needs more attention than a furnace that rests all summer.
- Filters every one to three months, and a clear outdoor coil
- A working condensate drain and float switch
- A yearly check of the defrost cycle and the backup heat
Light frost that melts every hour or so is normal defrost; ice that builds into a block is not. New systems use lower-impact refrigerants such as R-454B, so an old outdoor unit and a new air handler don’t mix. See maintenance, lifespan and the refrigerant change.
Air-source or geothermal, ducted or ductless
For most Boston-area houses with ducts, or attics and basements that can hold them, a ducted air-source system is the practical choice, and it’s the only kind we install.
Ground-source systems draw heat from wells or buried loops and stay efficient in deep cold, but drilling makes them far more expensive, and many lots can’t take them. Ductless mini splits suit houses with no room for ducts or a single addition. See ducted vs ductless.