Representing a Systems Approach
to H
eating, Cooling, and Hot Water

RST Thermal is a Manufacturer's Representative, serving New England, for multiple leading manufacturers whose products offer a systems approach to comfortable heating and cooling. We provide technical and sales support to our wholesale distributor partners and contractors. For homeowners, we provide geographic lists of installing and servicing contractors to help them find the "best fit" for the project to be done. Over the twenty year history of the company, we have been involved with thousands of succcessful projects where contractors sold better equipment, consumers saved dramatic amounts of energy, and solutions were offered that provided the highest levels of comfort.

Richard Trethewey started RSTINC in 1989 to pioneer and offer his customers many of the best hydronic heating lines in the market. For over 30 years, beginning in 1979, Richard has been the Plumbing and Heating Expert for the PBS series, “This Old House/Ask This Old House.”  RST Thermal is the merging of three rep firms. In January, 2010, RSTINC merged with Thermal Sales to create RST Thermal. In January, 2011, RST Thermal acquired Kasten and Company to balance out the current line card.


RST  Thermal Line Card


Unico Small duct high velocity heating and cooling


RenewAire Energy Recovery Ventilators


Bard Geothermal Heat Pumps, Wall mounted HVAC units, Oil furnaces 


ZoneFirst Innovative zoning dampers & control boards for HVAC systems


IBC High quality stainless steel condensing boiler


Schwank Gas Fired Infra-Red Heaters


Infrasave Gas Fired Infra-Red Heaters


Soler & Palau Fans of all sizes and ERV's


AireTechnologies Dampers; fire or smoke


Niles Commercial ASME tanks


Pridiom Ductless Mini-Split


Crete-Heat Insulated under slab grid system for radiant


Axiom System pressurizers & ph Neutralizers


AIC Heat Exchangers; Brazed Plate, Plate & Frame, Shell & Tube


Drake Chillers 


EZ Route In-floor radiant heating and domestic hot water tubing channel system.



Affiliated Companies We Recommend





TE2 Engineering (TE2) to provide energy efficient solutions, specializing in the design of “green” mechanical systems.

Cape Cod FireLog, ( made of 100% recycled wood, no chemical additives, compressed at very high heat, burn longer and burn hotter with near smokeless flames, no odor, cleaner emissions, and minimal ash residue than typical firelogs. The Hydronic Heating Association was formed to set industry standards, educate contractors, and inform the public about the benefits of having a quality hot water system installed.


Hydronics Heating Association (HHA) is accessible from the website address




 RST Thermal Copyright 2010