A Dual-Fuel Hybrid System That Keeps a Chelmsford Home Comfortable Year-Round
A 100-year-old steam boiler in front, forced hot water in the addition, window AC units in summer, and an aging furnace on its last legs. Here’s how Pespisa paired a ducted Mitsubishi Hyper-Heat heat pump with a high-efficiency gas furnace to create a dual fuel heat pump system — efficient electric comfort most of the year, with dependable gas heat when New England turns brutal.
The homeowners wanted whole-home comfort, lower bills, and a $4,682 Mass Save rebate. Pespisa Company designed a hybrid Mitsubishi heat pump system that fit the home instead of fighting it.
When the heating system in this Chelmsford home started showing its age, the homeowner faced the question every New England household eventually runs into: replace like-for-like, or take the chance to do something smarter?
Pespisa designed a dual-fuel hybrid system. A ducted Mitsubishi Hyper-Heat heat pump now handles efficient heating and cooling through the home’s existing ductwork, and a new 97% AFUE Trane furnace stands by as backup heat for the coldest stretches of winter — the best of both worlds, with no ductwork to tear out.
Project Snapshot
| DETAIL | PROJECT INFORMATION |
| Location | Chelmsford, MA |
| Project Type | Dual fuel heat pump installation |
| Existing Issue | Aging gas furnace nearing end of service life |
| Heat Pump Installed | Mitsubishi Hyper-Heat ducted heat pump |
| Backup Heat | Trane 97% AFUE high-efficiency gas furnace |
| Distribution | Existing ductwork reused |
| Homeowner Goal | Efficient heating, modern cooling, and dependable backup heat |
| Rebate | Mass Save rebate applied |
| Best Fit For | Homeowners replacing an aging furnace who want heat pump efficiency without giving up gas backup |
What Is a Dual Fuel Heat Pump?
A dual fuel heat pump combines an electric heat pump with a gas furnace. The heat pump handles everyday heating and cooling, while the furnace provides backup heat when outdoor temperatures drop and the home needs extra heating power.
For many Massachusetts homes, this setup offers a practical middle ground. Homeowners can get the efficiency and cooling benefits of a heat pump without relying on one fuel source during the coldest parts of winter.
In this Chelmsford home, the system was designed around the existing ductwork. That helped keep the installation cleaner and avoided the need to open walls or ceilings for new distribution.
The Challenge
Replacing an aging furnace without giving up backup heat
The homeowner’s existing furnace was nearing the end of its service life. A standard furnace replacement would have restored heat, but it would not have solved the larger comfort goals: better efficiency, central cooling, and a more flexible system for year-round use.
The home also had existing ductwork worth keeping. That made a ducted heat pump a strong option, but going fully electric felt like a big step for a New England home that still needed dependable heat during deep winter cold.
The goal was clear: improve efficiency, add modern cooling, and keep reliable gas backup available when temperatures dropped.
Our Solution
A dual fuel heat pump with gas furnace backup
Pespisa installed a dual fuel heat pump system that works through the home’s existing ductwork. The Mitsubishi ducted heat pump now handles everyday heating and cooling, while the high-efficiency Trane gas furnace stands by as backup heat during the coldest stretches of winter.
Ducted heat pump:
- Mitsubishi PUZ-AK30NLHZ outdoor unit
- 30,000 BTU single-zone Hyper-Heat system
- Installed on an 18-inch stand
- Mitsubishi PAA-BA30NL ducted air handler tied into the existing duct system
Gas furnace backup:
- Trane S9V2 two-stage natural gas furnace
- 40,000 BTU input
- 97% AFUE efficiency rating
- New media filter system for cleaner air and easier maintenance
The system is integrated so the heat pump does most of the daily work, while the furnace is available when outdoor conditions call for extra heating capacity.
Why a Dual Fuel Heat Pump Was the Right Fit
A single-system replacement would not have delivered the same balance of efficiency, comfort, and peace of mind. A dual fuel heat pump made sense for this Chelmsford home because it solved several problems at once.
Heat pump first:
The Mitsubishi Hyper-Heat system provides efficient heating and cooling for much of the year, helping reduce reliance on gas during milder heating conditions.
Gas furnace backup:
The 97% AFUE Trane furnace gives the homeowner dependable backup heat when Massachusetts winter temperatures become more demanding.
Existing ductwork reused:
Because the ducted air handler could connect to the home’s existing duct system, the project avoided unnecessary disruption from major duct replacement.
Cooling added:
The heat pump also provides central cooling, giving the homeowner a more complete comfort upgrade than a basic furnace replacement.
The Result
The homeowner now has a dual fuel heat pump system designed for year-round comfort: efficient electric heating through much of the season, central cooling in summer, and a high-efficiency gas furnace ready for deep winter conditions.
Project Highlights:
- $2,812.50 Mass Save rebate earned on the install
- Ducted Mitsubishi Hyper-Heat heat pump installed
- 0% financing available through Mass Save
- Net project cost after rebate: $19,546.50
- 97% AFUE high-efficiency gas furnace as backup heat
- Central cooling added
This gave the homeowner a practical upgrade from an aging furnace without forcing a full switch to electric-only heating.
Equipment Spec Sidebar
| System | Dual-fuel hybrid: ducted heat pump + high-efficiency gas furnace |
| Heat pump (outdoor) | Mitsubishi PUZ-AK30NLHZ — 30,000 BTU, single-zone Hyper-Heat |
| Air handler (indoor) | Mitsubishi PAA-BA30NL ducted cased coil |
| Gas furnace | Trane S9V2 — 40,000 BTU input, 97% AFUE, two-stage |
| Air quality | Media filter system |
| Distribution | Existing ductwork reused |
| Mass Save rebate | $2,812.50 |
| Net cost after rebate | $19,546.50 |
| Location | Chelmsford, MA |
Dual Fuel Heat Pump vs. Standard Furnace Replacement
For homeowners with an aging furnace, replacing it with another furnace may seem like the simplest option. But a dual fuel heat pump can offer more flexibility.
A standard furnace replacement restores heat, but it does not add efficient cooling or reduce gas usage during milder weather. A dual fuel heat pump gives the home both heating and cooling from the heat pump, while still keeping gas backup available when needed.
This is why hybrid systems can be a strong fit for Massachusetts homeowners who want better efficiency but are not ready to rely on a fully electric system.
Mass Save Rebates Helped Lower the Cost
This dual fuel heat pump system qualified for a Mass Save rebate, helping reduce the homeowner’s final project cost. The project also had access to 0% Mass Save financing, making the upgrade easier to manage.
Because rebate eligibility can vary by home, equipment, system design, and current program rules, homeowners should confirm available incentives before installation. Pespisa can help review the system options and rebate process during the consultation.
This dual-fuel system qualified for $2,812.50 in Mass Save rebates and 0% Mass Save financing, bringing the net cost down to $19,546.50.
Talk to Pespisa about your rebate →
Replacing an aging furnace? Consider a hybrid.
If your furnace is nearing the end of its life and you want efficient heating, modern cooling, and dependable backup heat, a dual fuel heat pump may be the right fit.
Pespisa designs heat pump and hybrid heating systems around the home, the ductwork, and the comfort goals of each homeowner.
Schedule a free heating consultation to find out whether a dual fuel heat pump system makes sense for your home in Chelmsford or the surrounding Middlesex County area.
FAQs About Dual Fuel Heat Pumps
A dual fuel heat pump is a heating and cooling system that combines an electric heat pump with a gas furnace. The heat pump handles everyday heating and cooling, while the furnace provides backup heat when outdoor temperatures are very cold.
Yes, a dual fuel heat pump can be a strong option for Massachusetts homes because it offers efficient heat pump performance during much of the year while keeping gas backup available during colder winter conditions.
In many homes, yes. If the existing ductwork is properly sized, sealed, and in good condition, a ducted heat pump can often use the current duct system. Pespisa evaluates the ductwork before recommending this type of setup.
It depends on the home and the homeowner’s goals. A standard furnace replacement restores heat, but a dual fuel heat pump can add efficient heating, central cooling, and backup gas heat in one integrated system.
No. In a properly designed dual fuel system, the heat pump handles much of the heating load. The furnace turns on when conditions call for backup heat, such as during colder outdoor temperatures.
It may qualify depending on the equipment, system design, home, and current Mass Save program requirements. Homeowners should confirm eligibility before installation.