Who We Serve

*Commercial Industry
*Goverment Buildings
*Property Management Firms
*Shopping Centers
*Tenant Fit-outs
*New Contruction & More!

About Us


A family owned and operated business, Interstate Service Company was established by James Ashen in 1972. Interstate Service Company (ISC) is a full service heating, ventilation, air conditioning and refrigeration company. We provide installation, service and repair of all types and sizes of commercial and industrial systems. ISC specializes in construction, maintenance, and service contracts.
Given our workforce of approximately fifty (50) fulltime employees, ISC is well positioned to handle all of your HVACR requirements. Employees include highly qualified steamfitters, HVACR technicians, Project Managers, Certified Welders, Apprentices, and a highly motivated team of Administrative Personnel. 
As reflected by our high percentage of return business, ISC has been providing the highest quality of service to clients in the Maryland, DC and Virginia area for 36 years. This continued success attests to the quality, capability, and consistency of our work, instilling our owners and general contractors with secure knowledge that their projects are in the hands of one of the most respected contractors in the area.

Our goal at Interstate Service Company, Inc. is to provide you with quality equipment, highly trained service technicians, superior customer service and competitive pricing. We sincerely thank you for your interest in Interstate Service Company, Inc. and look forward to a successful business relationship.