Tandem Mechanical
Home/Heating/Boiler Replacement & Installation

Boiler Replacement & Installation in MA & CT

Professional boiler installation and replacement — gas, oil, steam & hydronic. $1,000 off qualifying installations. QuickBooks financing available.

Call Now
Licensed & Insured
Financing Available
Residential & Commercial

Reliable Boiler Installation Done Right the First Time

Boiler Replacement & Installation is part of the building heating system and may involve heat production, circulation or airflow, thermostats and controls, electrical components, safety devices, pumps, valves, distribution equipment and related piping or ductwork. We diagnose the system before recommending repair or replacement so the work addresses the actual cause of the comfort problem.

What This Job Entails

Boiler Replacement & Installation — The Full Breakdown

Exactly what we do, what you get, and what to expect — answered the way a careful customer would ask.

What exactly is included in this service?

  • Heat loss calculation and boiler sizing assessment
  • Removal and disposal of the existing boiler and associated components
  • Supply and installation of the new boiler unit
  • Hydronic piping connections and any required modifications to the near-boiler piping
  • Gas or oil supply connection to the new equipment
  • Venting installation or reconfiguration as required for the new unit
  • Integration with existing zone controls, circulators, and thermostats
  • System fill, purge, pressure test, and combustion startup
  • Customer walkthrough covering system operation, thermostat use, and basic maintenance

What is NOT included?

  • Building permit fees charged by the municipality
  • Replacement or upgrade of existing distribution piping beyond the boiler room
  • Electrical panel upgrades or new dedicated circuits if required
  • Wall, ceiling, or floor repair following any access work
  • After-hours or weekend scheduling premiums
  • Asbestos abatement if present on existing piping insulation

How long does the job take?

Expected duration: A standard residential boiler replacement typically takes 6 to 8 hours for a single-day installation. More complex projects involving zoning upgrades, venting reconfiguration, or piping system modifications may require 1.5 to 2 full days. Commercial installations are scoped individually and may span multiple days depending on system size.

Is the work warrantied or guaranteed?

Tandem Mechanical warranties all workmanship on boiler installations for a period of one year from the date of installation. Manufacturer warranties on the installed boiler and components vary by brand and model and are passed through directly to the customer; our team will provide you with the applicable warranty documentation at the time of installation. Warranty coverage requires that the system be operated within its designed parameters and that annual maintenance be performed.

Complete Boiler Replacement & Installation Solutions

Professional service covering the full scope of boiler replacement & installation needs.

New Boiler Installation

Full installation of a new hydronic boiler system including all near-boiler piping, expansion tank, controls, and venting in new construction or complete system replacement scenarios.

Boiler Replacement

Remove and replace an existing failed or end-of-life boiler with a properly sized, code-compliant new unit while reusing or upgrading existing distribution piping and zones as appropriate.

Boiler System Repair

Diagnosis and repair of boiler components including circulator pumps, zone valves, aquastats, pressure relief valves, expansion tanks, and gas valves when the boiler vessel itself remains serviceable.

Annual Boiler Maintenance

Seasonal tune-up including burner cleaning, combustion analysis, flue inspection, pressure and relief valve testing, and controls verification to keep your system running safely and efficiently.

Boiler Diagnostic Service

Thorough diagnostic evaluation of a poorly performing or failing boiler system to identify root causes and provide clear repair-or-replace recommendations.

Benefits of Boiler Replacement & Installation

Improved heating efficiency with modern condensing boiler technology (up to 95%+ AFUE)
Reduced fuel consumption and lower energy bills over the system's life
Consistent, even heat delivery throughout all zones
Quieter operation compared to older, worn equipment
Full code compliance and proper permitting for peace of mind
Compatibility with smart thermostats and advanced zone controls
Extended system lifespan with a properly commissioned installation
Reduced risk of carbon monoxide hazards associated with deteriorating older equipment

Signs You May Need Boiler Replacement & Installation

If you're experiencing any of these issues, a technician can diagnose the problem and recommend the right solution.

Your boiler is over 15–20 years old and repair costs are increasing
The system frequently loses pressure or requires regular manual resets
Uneven heat distribution across zones or radiators
Visible corrosion, cracks, or leaks on the boiler vessel or heat exchanger
Rising fuel bills despite similar usage patterns
The system uses obsolete controls or components that are no longer serviceable
Your home addition or renovation requires expanded heating capacity
You are converting from another fuel type or heating system
Repair First

Repair When It Makes Sense. Replace Only When It Makes Sense.

Our first job is to diagnose the problem. We do not assume a failed system automatically needs replacement.

A boiler repair makes sense when the unit is less than 10–12 years old, the heat exchanger is intact, and the repair cost is a reasonable fraction of replacement cost. However, once a boiler exceeds 15–20 years of age, shows signs of heat exchanger failure or significant corrosion, requires repeated repairs, or operates below 80% AFUE on a fuel-intensive system, replacement is almost always the more economical long-term decision. Condensing boilers operating at 90–95%+ AFUE can dramatically reduce annual fuel costs, often shortening the payback period on a new installation. Tandem Mechanical will give you an honest assessment of your existing equipment so you can make an informed decision.

If replacement is the practical choice, qualifying installation financing may be available. Subject to approval.

Types of Systems We Service

Gas-Fired Condensing Boilers

High-efficiency modulating condensing boilers (90–95%+ AFUE) such as those from Navien, Weil-McLain, Buderus, and Viessmann, designed for closed-loop hydronic systems with low return water temperatures.

Gas-Fired Atmospheric and Power-Vent Boilers

Traditional mid-efficiency natural gas or propane boilers using atmospheric or induced-draft venting, commonly found in existing residential systems.

Oil-Fired Boilers

Residential and light commercial oil boilers using pressure-gun burners, including both older cast-iron designs and modern high-efficiency units compatible with biofuel blends.

Cast-Iron Sectional Boilers

Durable cast-iron boilers commonly installed in older New England homes, valued for longevity but typically operating at lower efficiency ratings than modern alternatives.

Steam Boilers

One-pipe and two-pipe steam heating systems common in older residential and multi-family buildings throughout the region, requiring specialized knowledge of steam pressure, condensate return, and near-boiler piping.

Combination Boilers (Combi Boilers)

Compact units that provide both space heating and domestic hot water from a single appliance, ideal for smaller homes or spaces with limited mechanical room footprint.

Equipment Brands We Service

Weil-McLainBuderusViessmannNavienBurnhamPeerlessSlant/FinCrown Boiler

Our Boiler Replacement & Installation Process

1

Initial assessment: evaluate existing system, heating load, fuel type, venting options, and available mechanical space

2

Load calculation: perform or review heat loss calculations to properly size the replacement boiler

3

Equipment selection: recommend boiler model, efficiency rating, and configuration suited to your home or building

4

Permit application: pull required mechanical permits with the local building department before work begins

5

System shutdown and removal: safely drain, disconnect, and remove the existing boiler and associated components

6

New boiler installation: set and connect the new unit including near-boiler piping, expansion tank, air separators, and pressure relief valve

7

Venting and combustion air: install or modify flue venting and combustion air provisions per manufacturer and code requirements

8

Controls and wiring: connect aquastat, zone controls, circulator pumps, and thermostat wiring

9

System fill, purge, and startup: fill and bleed the system, verify correct pressure and flow, perform combustion analysis, and confirm all zones are operating

10

Customer walkthrough: explain system operation, maintenance requirements, and thermostat controls

Residential & Commercial Boiler Replacement & Installation

Residential Service

For homeowners, a boiler replacement is one of the most impactful mechanical investments you can make. Modern condensing boilers are dramatically more efficient than the equipment installed 20 or 30 years ago, and a properly sized new system will deliver more consistent comfort with lower fuel bills. Tandem Mechanical handles the entire process — permits, removal of the old unit, new installation, zone controls, and thermostat integration — so you don't have to coordinate multiple contractors. We're experienced with the older housing stock common throughout Western Massachusetts and the Connecticut River Valley, including homes with steam systems, radiant floors, and multi-zone baseboard heat.

Commercial Service

Light commercial and multi-unit residential buildings place higher demands on boiler systems, often requiring staged or modular boiler configurations, building automation system (BAS) integration, and compliance with commercial mechanical codes. Tandem Mechanical has experience with commercial hydronic heating systems in apartment buildings, schools, houses of worship, and mixed-use properties across the region. We can design and install single or paired boiler systems with proper lead-lag controls, low-loss headers, and building management integration to maximize efficiency and redundancy for building owners and property managers.

Performance & Quality Factors

The efficiency and longevity of a boiler installation depend heavily on factors beyond the boiler itself. Proper hydraulic separation between the boiler loop and distribution system, correctly sized circulator pumps, adequate expansion tank pre-charge, and appropriate system water treatment all play critical roles. Condensing boilers in particular require low return water temperatures — typically below 130°F — to achieve their rated efficiency, which means the distribution system design must be compatible. Tandem Mechanical evaluates these factors on every installation to ensure your new boiler delivers its full rated performance throughout its service life.

Maintenance & Troubleshooting

Annual maintenance is essential for keeping a boiler system safe, efficient, and code-compliant. A proper boiler tune-up includes cleaning the burner and heat exchanger surfaces, performing a combustion analysis to verify proper air-to-fuel ratio, inspecting the flue and venting for obstructions or deterioration, testing the pressure relief valve and low-water cutoff, checking expansion tank pressure, and inspecting all controls and safety devices. For oil-fired systems, annual service should also include nozzle and filter replacement. Keeping up with maintenance extends equipment life, preserves manufacturer warranties, and reduces the risk of mid-winter failures.

Service Areas for Boiler Replacement & Installation

Tandem Mechanical installs and replaces boilers throughout Western Massachusetts, including the Pioneer Valley and surrounding communities, as well as Worcester County and Northern Connecticut. The region's older housing stock — much of it built before 1980 — relies heavily on hydronic heating systems, and our team has extensive experience with the cast-iron boilers, steam systems, and oil-fired equipment commonly found in homes and commercial buildings across the area. We're familiar with local permit requirements and inspectional services processes in the communities we serve, helping to keep your project on schedule.

Communities We Serve

Select a covered town where this service is currently listed for local details and booking.

AgawamMAAmherstMAAshburnhamMAAshfieldMAAtholMAAuburnMABarreMABelchertownMABellinghamMABerlinMABernardstonMABlackstoneMABlandfordMABoltonMABoylstonMABrimfieldMABrookfieldMABucklandMACharlemontMACharltonMAChesterMAChesterfieldMAChicopeeMAClintonMAColrainMAConwayMACummingtonMADeerfieldMADouglasMADudleyMAEast BrookfieldMAEast LongmeadowMAEasthamptonMAEnfieldCTErvingMAFitchburgMAGardnerMAGillMAGoshenMAGraftonMAGranbyCTGranvilleMAGreenfieldMAHadleyMAHampdenMAHardwickMAHartfordCTHarvardMAHatfieldMAHawleyMAHeathMAHoldenMAHollandMAHolyokeMAHopedaleMAHubbardstonMAHuntingtonMALancasterMALeicesterMALeominsterMALeverettMALeydenMALongmeadowMALudlowMALunenburgMAMendonMAMiddlefieldMAMilfordMAMillburyMAMillvilleMAMonroeMAMonsonMAMontagueMAMontgomeryMANew BraintreeMANew SalemMANorth BrookfieldMANorthamptonMANorthboroughMANorthbridgeMANorthfieldMAOakhamMAOrangeMAOxfordMAPalmerMAPaxtonMAPelhamMAPetershamMAPhillipstonMAPlainfieldMAPrincetonMARoweMARoyalstonMARussellMARutlandMAShelburneMAShrewsburyMAShutesburyMASimsburyCTSouth HadleyMASouthamptonMASouthboroughMASouthbridgeMASouthwickMASpencerMASpringfieldMASterlingMASturbridgeMASuffieldCTSunderlandMASuttonMATempletonMATollandMAUptonMAUxbridgeMAWalesMAWareMAWarrenMAWarwickMAWebsterMAWendellMAWest BoylstonMAWest BrookfieldMAWest SpringfieldMAWestboroughMAWestfieldMAWesthamptonMAWestminsterMAWhatelyMAWilbrahamMAWilliamsburgMAWinchendonMAWindsorCTWorcesterMAWorthingtonMA
Real Customer Reviews

What Customers Say About Our Boiler Replacement & Installation

Google

“I am a first time home buyer and not familiar with the boiler/heating system in my home and was apprehensive about finding a service provider to service my boiler. I def. made the right choice choosing Tandem Mechanical to service my boiler system. I needed my boiler serviced and Josh and Sam arrived today and serviced the boiler in a professional manner. Josh explained everything they were going to do before they started work. They were punctual, professional and went above and beyond. They also addressed questions I had on two other issues, one which could have been a problem later on if not addressed. I was very impressed with these guys and also the lady I spoke with re: setting up the appointment. Thank you TM! Much appreciated.”

Dee

Heating

Angi

“Joshua and his crew was experienced , kind and honest, awesome work”

LINDA B.

Angi

“Very nice. Knowledgeable Would definitely recommend”

Anne P.

Angi

“Josh and his team were awesome. They gave me a quote quickly, came out a few days later (our job wasn't a rush), and did an awesome job. They installed our water heater and vented it outside in under 3 hours. They left our basement spotless after the install too. Very very friendly and polite as well. If I ever need any other plumbing/HVAC work I'm going to reach out.”

Matt J.

Pittsfield · Water Heater - Install or Replace

Angi

“Hired them for emergency service and they did a great job on the same day. Pricing was what we expected, about 30% less then other quotes we got from franchises .”

Alon C.

Leominster · Water Heater - Install or Replace

Angi

“Very pleasant and professional and we would hire him again.”

Paula F.

Read More Customer Reviews →

Boiler Replacement & Installation FAQ

Ready to Replace Your Boiler? Let's Get Started.

Tandem Mechanical is ready to help. Call now or book online.

Call 413-667-4998

Boiler replacement is a significant investment in your home or building's comfort and efficiency. Tandem Mechanical can discuss available financing options to help make a new high-efficiency boiler installation more accessible. Ask us about current programs when you request your estimate.

CALL NOW · NO HEAT?