Project Spotlight: Mitsubishi ecodan® Air-to-Water Heat Pump Installation in Winchester, MA

As homeowners throughout Massachusetts and Southern New Hampshire look for ways to reduce energy costs, improve comfort, and transition away from fossil fuels, air-to-water heat pump technology is becoming one of the most efficient solutions available. Recently, Denommee Plumbing, HVAC & Electric completed a comprehensive oil-to-electric heating conversion featuring a state-of-the-art Mitsubishi ecodan® Air-to-Water Heat Pump System with integrated domestic hot water production.

This project replaced an aging oil-fired hydronic heating system with a high-efficiency electric heating solution designed to deliver reliable comfort even during New England's coldest winter temperatures.

Project Overview

The homeowner's existing oil boiler and oil tank had reached the point where replacement made more sense than continued repairs and rising fuel costs. Our team designed and installed a complete Mitsubishi ecodan® air-to-water heat pump system capable of providing both hydronic heating and domestic hot water while significantly improving overall energy efficiency.

System Specifications

Heating Application: Hydronic Heating with Domestic Hot Water

Fuel Source: Electric

Design Heating Load: Approximately 24,000 BTU/h

Supply Water Temperature: Up to 140°F to support existing hydronic heating distribution

The system was carefully selected to exceed the home's heating requirements at design conditions while maintaining compatibility with the existing hydronic distribution system.

Equipment Installed

Mitsubishi Ecodan Cold Climate Heat Pump

Outdoor Unit: Mitsubishi ecodan® WUZ-SA48NMZ

The Mitsubishi ecodan® is a cold-climate inverter-driven air-to-water heat pump engineered specifically for northern climates. Unlike traditional heating systems that generate heat through combustion, the ecodan® extracts heat from the outdoor air and transfers it into the home's hydronic heating system.

Benefits include:

• Exceptional cold-weather performance
• Reduced energy consumption
• Lower operating costs
• Quiet operation
• Elimination of on-site fuel storage
• Reduced carbon emissions

Mitsubishi Ecodan Hydrobox

Indoor Hydronic Module: ERSF-NM6E

The Hydrobox serves as the heart of the system, integrating advanced controls, circulators, and system management functions into one compact package. This component efficiently transfers heat from the outdoor unit into the home's heating and domestic hot water systems.

Viessmann Stainless Steel Indirect Water Heater

To provide reliable domestic hot water, our team installed an 80-gallon Viessmann stainless steel indirect water heater. This high-quality tank offers excellent durability, corrosion resistance, and long-term performance.

Installation Scope

The project involved much more than simply replacing heating equipment. Our technicians completed a full mechanical system upgrade designed for long-term reliability and performance.

Hydronic System Installation

The installation included:

• Outdoor heat pump mounted on a raised, leveled, vibration-isolated platform
• Indoor hydronic module installation
• New buffer tank and expansion tank
• New indirect water heater
• Domestic hot water priority controls
• Zone control panel installation
• New supply and return hydronic piping
• New pumps and valves
• Complete hydronic heat trim package

Refrigeration and System Commissioning

To ensure optimal performance and manufacturer compliance, our HVAC team:

• Installed refrigerant piping between indoor and outdoor equipment
• Pressure tested the system with nitrogen
• Evacuated refrigerant lines below 500 microns
• Charged the system according to Mitsubishi specifications
• Completed full startup and commissioning procedures
• Registered equipment for manufacturer warranty coverage

Electrical Upgrades

A successful electrification project often requires electrical improvements to support the new equipment. Our licensed electricians completed:

• Installation of a new 100-amp subpanel
• New air conditioning feed with whip and disconnect
• Electric backup heat feed
• Dedicated 220V appliance circuit
• Panel modifications and breaker installation
• Complete line voltage wiring and connections

These upgrades ensure the new heat pump system operates safely and efficiently for years to come.

Oil Boiler and Oil Tank Removal

One of the most satisfying aspects of this project was helping the homeowner completely eliminate their dependence on heating oil.

Our team safely removed and disposed of:

• Existing oil-fired boiler
• Associated near-boiler piping
• Existing hot water tank
• Above-ground oil storage tank
• Related fuel lines above the slab

By removing the oil system entirely, the homeowner no longer has to worry about fuel deliveries, fluctuating oil prices, or maintaining an aging combustion appliance.

Advantages of Air-to-Water Heat Pumps

Air-to-water heat pumps are becoming increasingly popular because they provide many benefits beyond energy savings.

Maintain Existing Hydronic Heating

Many homeowners love the comfort of hydronic heating but want to move away from oil. Air-to-water technology allows homeowners to retain their existing baseboard, panel radiator, or radiant heating systems while replacing the heat source with an efficient electric alternative.

Reduced Energy Costs

Modern inverter-driven heat pumps can deliver multiple units of heat energy for every unit of electricity consumed, helping reduce overall heating expenses compared to conventional oil systems.

Improved Environmental Impact

Electrification helps reduce greenhouse gas emissions and supports Massachusetts' clean energy goals while improving overall home efficiency.

Year-Round Comfort

With advanced controls and integrated domestic hot water production, homeowners enjoy reliable heating and hot water from a single high-performance system.

Mitsubishi ecodan® Air-to-Water Heat Pumps: The Future of Home Heating, Cooling & Hot Water

Mass Save Incentives Help Reduce Costs

One of the biggest advantages of converting from oil to a qualifying heat pump system is access to substantial rebates and financing options.

For this project:

• Installed Project Cost: $32,872
• Mass Save Instant Rebate: $7,950
• Net Investment After Incentives: $24,922

Qualified homeowners may also be eligible for the Mass Save Heat Loan Program, offering:

• Up to $25,000 financing
• 0% interest
• Terms up to 84 months

These incentives make upgrading to high-efficiency heat pump technology more affordable than ever.

Industry-Leading Warranty Protection

As a Mitsubishi Diamond Elite Contractor, Denommee Plumbing, HVAC & Electric provides access to enhanced manufacturer warranty protection.

Warranty coverage includes:

• 12-Year Compressor Warranty
• 12-Year Parts Warranty
• 1-Year 100% Labor and Installation Warranty from DPHE

Our team also includes a complimentary first-year maintenance service to help ensure optimal system performance.

Peace of Mind Service Program Membership Included

This installation also includes enrollment in our Peace of Mind Service Program Membership, designed to help homeowners protect their investment and prevent unexpected breakdowns.

Membership benefits include:

• Annual whole-home plumbing, HVAC, and electrical inspections
• Priority scheduling
• Waived dispatch fees during regular service hours
• Discounted maintenance services
• Loyalty credits toward future upgrades
• Member-only pricing and coupons
• Dedicated member phone support
• Fire, smoke, and carbon monoxide safety inspections
• Documentation and recommendations for future home improvements

The program helps homeowners stay ahead of potential issues while maximizing the lifespan and efficiency of their home comfort systems.

Why Choose Denommee Plumbing, HVAC & Electric?

Denommee Plumbing, HVAC & Electric specializes in heat pump installations, oil-to-electric conversions, hydronic heating systems, plumbing, electrical services, and home electrification projects throughout Massachusetts and Southern New Hampshire.

Our licensed technicians and electricians provide turnkey solutions that include system design, permitting, installation, startup, and ongoing maintenance. As a Mitsubishi Diamond Elite Contractor and Mass Save Heat Pump Leader Network Member, we help homeowners maximize comfort, efficiency, and available incentives.

If you're considering replacing an aging oil boiler or exploring air-to-water heat pump technology, contact Denommee Plumbing, HVAC & Electric today to schedule a consultation and learn how much you could save with a modern high-efficiency heating system.

📞 Get Started: Request Your Free Heat Pump Consultation Today!

Upgrading your heating and cooling system has never been more affordable! Take advantage of Mass Save heat pump rebates, 0% financing, and expert installation with Denommee Plumbing, HVAC & Electric.

📱 Text us at (857) 226-9140
🌐 Visit: www.DenommeePlumbing.com

Our team is ready to help you maximize your savings and upgrade to a more energy-efficient, comfortable, and environmentally friendly home. Request your free consultation today!