We know boilers and radiant heat systems!Design-Install-Service-Repair For Seattle

  • Steam & Hot Water
  • Radiant Floor and Ceiling
  • Radiators
  • Domestic Hot Water
  • Tub Warming
  • Swimming Pools
  • Hot Tubs
  • Greenhouses and more

Who should you call for custom boiler work in Seattle?Seattle radiant heat install

Carlson Mechanical specializes in custom boiler work, including expert installation, repair, service, and troubleshooting on everything from modern high-efficiency boilers to rare and exotic systems of yesteryear.

We provide residential and commercial service to the entire Seattle metro area including the Eastside communities from Woodinville to Bellevue to Renton.

Our friendly and knowledgeable technicians work on residential, multi-family and light commercial projects of all sizes. They can install your new custom boiler or hot water heat system; we even install and service pool boilers and water heaters but do not work on forced air systems.

Installing radiant heat in your home?Seattle Hot-water heat system

The craftsmen at Carlson Mechanical are experts at designing and installing radiant heat systems in new or older homes throughout the Seattle area.

Whether you call it radiant, hot-water or hydronic heat, it offers the highest comfort level with its even natural heat. Plus, it eliminates dust and contaminants of forced air systems making it perfect for people with allergies or asthma.

Pick from several delivery systems from radiant floor heating to contemporary panel radiators to stylish heated towel bars for your bathroom. For added convenience, we can install a smart thermostats to control your new system so you can change the temperature settings via your phone or tablet.

Why choose us for your remodeling or install?

We believe communication is the key to a successful install so to ensure all goes well from start to finish, we follow these best practices.

  • Easy to understand estimates
  • Answers to all your questions
  • Follow-up after project completion

Whatever your needs, our craftsmen can create an elegant system designed to last a lifetime.  Contact us to schedule your free estimate for a radiant heating system in your home or business.

Benefit from our experience working with contractorsInstall Radiant Heat Seattle

Carlson Mechanical has worked with a variety of general contractors in Seattle, Snohomish and Eastside areas on new construction and remodeling projects.

Our vast experience in hot water heat systems means we can design and install the perfect configuration whether you're building a custom home or remodeling your house.

We think it speaks well that the same contractors come back to us year after year because they trust our work and know we treat all customers with respect.

In addition, we don’t disappear after the work is done.  We stay in touch to make sure the system is operating correctly and our customers are happy with their new heating system.

Your company can really be proud of your employees, their work in putting the new boiler furnace in my home. They were very organized, efficient and worked steadily, even when answering the many questions given to them. They were always on time, bright and cheerful and friendly all the time they were here.

The Hoalonds

Ready for the steamy details?

Just click any thumbnail for a detailed description.

  • Knight Fire Tube Boiler
  • Noble Fire Tube Boiler
  • Lochnivar Knight XLT
  • Burnam Gas Boiler
  • Viessman Vitodens Boiler
  • Burnham Oil Boiler

Residential Lochnivar Knight Fire Tube Boiler

High Efficiency Wall Mounted Boiler

Lochnivar Knight Fire Tube boiler

This Energy Star compliant wall mounted boiler is the best green choice for residential and light commercial uses. Innovative features include the SMART SYSTEM control and Loch-N-Link USB drive setup, which put it far ahead of other boilers in its class.


  • 95% AFUE efficiency
  • Updated SMART SYSTEM control
  • ASME Stainless steel heat exchanger
  • 7 wall mount models: 55,000-399,999 BTU/HR
  • Modulating burner with up to 10:1 turndown
  • Low NOx operation
  • CON-X-US Remote connect capable
  • Warranties: Limited 15-year heat exchanger, Limited 5-year parts

Residential Noble Fire Tube Combi Boiler

Hot Water and Space Heating in 1 Unit

Noble Fire Tube Combi boilerThe space saving Noble Combi boiler delivers domestic hot water and comfortable home heating for homes with 1 or 2 bathrooms. Energy Star rated, it's an all-in-one money saving solution for endless hot water and lower energy bills.


  • 95% AFUE efficiency
  • SMART Control user-friendly LCD dispay with diagnostic info in real words
  • 10:1 Turndown ratio
  • Faster response time eliminates cold water sandwich
  • Industry-leading DHW delivery up to 4.8 GPM
  • Efficient patented fire tube design with stainless steel heat exchanger
  • 3 sizes: 110,000, 150,000 and 199,999 BTU/HR

Lochnivar Knight XL

High Efficiency Commercial Condensing Boiler


Smart choice for commercial use, its innovative features and high efficiency make it the best green choice for the environment. Up to 8 boilers can be installed together using the built-in cascading sequencer to meet high heating demands.


  • Up to 94.6% thermal efficiency
  • Low NOx certified (less than 20 ppm NOx)
  • SMART SYSTEM controls with multi-colored LCD display panel
  • Built-in cascade sequencer to meet high heating capacity demands
  • Fully modulating burner with 5:1 turndown to increase efficiency
  • 2 in 1 stainless steel heat exchanger reduces heat loss
  • 5 models ranging from 399,999-800,000 BTU/HR
  • Flexibility with 7 venting options up to 100 feet

Burnham Gas-Fired Steam Boiler

Burnham Independence Series Boilers


American made, Burnham boilers are built to last. The Independence cast iron steam boiler is the best choice for efficient, quiet and reliable steam heating. With flexible venting options, it can be installed in homes with or without a chimney.


  • Up to 82% AFUE efficiency
  • Natural or LP gas
  • Chimney with fuel saving vent damper or power vent configuration
  • Insulated steel jacket reduces boiler heat loss
  • Step-opening gas valve for smooth quiet start-up
  • Durable cast iron heat exchanger & stainless-steel burner
  • Electric ignition (sizes 3-9)
  • 10 sizes to fit your needs-rated output from 62 to 385 MBH

Viessman Vitodens 100-W

Gas-Fired Wall-Mounted Condensing Boiler


The perfect mix of performance, quality and value, this space saving wall-mounted condensing boiler fits any home and budget. It’s quieter than most refrigerators and its high efficiency will save homeowners money on utility bills.


  • 95% AFUE efficiency
  • Low-emission combustion
  • User-friendly LCD touchscreen boiler control
  • Self-cleaning heat exchanger for longer life
  • Stainless steel Inox-radial heat exchanger for peak performance
  • Optional built-in on-demand domestic hot water kit
  • Works in altitudes up to 10,000 ft.
  • Many venting options up to 200 ft.

Burnham Oil-Fired Steam Boiler

High Efficiency MegaSteam™ Oil-Fired Steam Boiler


American made, the Megasteam offers efficiency, performance and reliability. Burnham’s advanced engineering has built a cast-iron boiler that produces steam that’s 99% dry making it the most efficient oil-fired steam boiler available.


  • 86% AFUE high efficiency
  • ENERGY STAR certified
  • 99% dry steam increases efficiency
  • Unique 3-pass cast iron heat exchanger reduces heat loss
  • Durable high corrosion resistance stable waterline
  • Unmatched Steam Boiler Warranty protection
  • 4 sizes to fit your needs (0.75 - 1.65 GPH)
  • Tankless hot water heater (coil) available

Design and Installation of Hot-Water Heat SystemsHot Water Heating System

In a hot water heating system, the boiler plays a central role as it heats the water or steam that is then circulated around the house.

Because of this, you want and need a boiler that is reliable and delivers service every day.

The boilers, installed by Carlson Mechanical, are from trusted leading boiler manufacturers, such as Lochinvar, Burnham, Viessmann and Triangle Tube. 

It’s important to know that not everyone installs boilers the same way!

Using the latest technology, combined with proven, time-tested engineering, Carlson Mechanical has developed its own unique installation method to provide maximum comfort and last for the life of your Seattle area home.

One of the smartest things we have done is change to your high efficiency gas boilers. Since we did it, the cost of heating our 3 buildings has gone down over 50%. The removing and installing operations went seamlessly and all the personnel that worked on the project were outstanding and extremely conscientious to our needs.

Ron and Nancy, Green Lake Cooperative


We can use your boiler to heat your domestic water 50 to 500% faster and 10 to 45% cheaper than a conventional gas or electric water heater.  Your same boiler can be used to heat a hot tub, swimming pool, or even a green house.

Experts in Steam SystemsRepair Hot Water Heat Systems

More art than science, the correct replacement and repair of a steam boiler is a rare skill today.

Installing new, modern steam boilers is a specialty of Carlson Mechanical.

The boiler must be viewed as part of your heating system that also includes your home's radiators, air vents and piping.

The craftsmen at Carlson Mechanical have the knowledge and skill to ensure a complete, properly working steam heat system.

Ultimate control-whole home automation

Once your new hot water heating system is in place, we offer thermostats so you can control the temp in your home no matter where you are-at the office, stuck in traffic or away on holiday.

Whole home automation gives you the freedom to check and change your thermostat from your phone, laptop or anywhere that you have internet access.

You’ll have the ultimate control over your home’s heating system and that’s not only convenient, it’ll save you money and energy.

Home automation

Plumbing service and repair

Our journeyman plumbers are licensed to handle gas piping repair and installation along with various re-piping projects and installing water heaters.

Our plumbers have over 90 years of combined experience so they can handle just about anything.