Heat Pump Brands
Your House Picks the Brand. Not Our Purchasing Agreement.
Most Connecticut contractors install one brand and tell you it is the best one. CellSun installs three, because a 1920 colonial in West Hartford with no ductwork and a 1994 ranch in Rocky Hill with a full duct system are not the same job and should not get the same equipment.
The Question Nobody Answers Straight
Ask five Connecticut HVAC companies which heat pump brand is best and you will get five different answers, each one matching the brand that company already stocks. That is not advice. That is inventory.
Here is what actually determines the right brand for your home, in order: whether you have usable ductwork, how cold the coldest room in your house gets, what you are heating with today, and what the total number has to be for the project to happen at all. Equipment brand is the last variable, not the first.
CellSun carries three lines so that the recommendation can follow the house.
Side by Side
Gree, KEEN and Mitsubishi, Compared Honestly
| Gree | KEEN | Mitsubishi | |
|---|---|---|---|
| Best for | Homes with existing ductwork | Homes pairing heat pump with solar | Older homes, no ductwork, cold rooms |
| System type | Central ducted split | Ducted air handler or multi zone ductless | Ductless multi zone, ducted, hybrid |
| Rated heating operation | Down to -22F on FLEXX models | AHRI cold climate certified | Down to -13F on Hyper-Heating INVERTER |
| Efficiency | Up to 18.5 SEER2 on the FLEXX ULTRA R32 | AHRI certified, ratings verified under native controls (CVP) | Up to roughly 19 SEER2 and 12.5 HSPF2 |
| Monitoring | Standard thermostat | Connected, CellSun sees faults remotely | kumo cloud app |
| Warranty posture | Manufacturer parts, CellSun labor in front | Manufacturer plus CellSun Comfort Plan | 10 year parts and compressor with registration |
| Relative install cost | Lowest | Middle | Highest |
| Energize CT rebate eligible | Yes | Yes | Yes |
| 1.99% Smart-E eligible | Yes | Yes | Yes |
Ratings vary by model. CellSun quotes the specific model and its actual rating on your proposal, not a marketing range.
Four Questions, Then a Recommendation
- 1
Do you have ductwork you can use?
If yes, a central ducted system is almost always the cheapest path and Gree leads. If no, forcing ducts into a Connecticut colonial means soffits, dropped ceilings and lost closet space, and a ductless multi zone from Mitsubishi wins on both cost and disruption.
- 2
How cold does the coldest room get?
Connecticut's winter design temperature sits near 7 degrees, which means the system has to hold the house on the coldest morning of the year, not on an average January day. If you have one room that never gets warm now, that room drives the equipment choice.
- 3
What are you heating with today?
Over 40 percent of Connecticut homes still heat with oil, according to the state's own heating portal. If you are on oil or propane, the operating cost swing is large enough that the cheapest qualifying heat pump beats staying put. If you are already on natural gas, the math is tighter and the equipment choice matters more.
- 4
Are you adding solar now or later?
A heat pump moves your heating load onto your electric bill. If solar is in the plan, the system should be sized and monitored with that in mind, which is the case for KEEN and the reason CellSun made it the house line.
Three Brands, One Install Standard
The brand on the outdoor unit is the part homeowners think about. The part that actually determines whether the system performs is the part they never see.
Manual J load calculation on every quote
Not a rule of thumb, not matching the tonnage of what is there now. Oversized heat pumps short cycle, fail to dehumidify, and cost more to run.
MeasureQuick verified commissioning
Every CellSun install is measured at startup and you get the System Vitals report. Most contractors install and leave. We hand you the numbers.
Rebate handled at install
CellSun handles the Energize CT rebate paperwork and applies it at install, so you are not filing and waiting.
Owner led project management
CellSun designs the system, specifies the equipment, pulls the permits, handles the Energize CT rebate and commissions the result. Installation is performed by our licensed HVAC installation partner. Cameron manages the project from assessment through final commissioning, and he is who you call afterward.
Energize CT Energy Optimization
What Connecticut Pays Toward Your Heat Pump
Energize CT's residential Energy Optimization incentive pays $1,500 per ton, up to $10,000 in combined incentives, at the rate in effect September 1 through December 31, 2026. The rate was $1,000 per ton from January through August and moved up on September 1. On a four ton project that is $2,000 more than the same job was worth in August.
$1,500
Per Ton
Sept 1 through Dec 31, 2026
$10,000
Combined Cap
Energize CT Energy Optimization
1.99%
Smart-E APR
5 year term up to $25,000
$0
Down Payment
No prepayment penalties
Program Requirements
- Residential Eversource or United Illuminating electric customer
- Equipment on the Energize CT Heat Pump Qualified Product List
- Installer in the Energize Connecticut Heat Pump Installer Network
- Full displacement of the existing heating system for the full rate. Partial displacement is a separate path requiring qualified integrated controls.
- Post installation inspections are random and mandatory. Failing to complete one forfeits the rebate.
There is no federal tax credit on a 2026 heat pump installation. Section 25C ended for equipment placed in service after December 31, 2025.
Honest Answers
Heat Pump Brand Questions
Get the Recommendation Before You Get the Quote
Free in home assessment. We measure the house, run the load calculation, and tell you which of the three fits. No obligation, and no pressure to pick the expensive one.