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Carl Wolf
(302) 326-2665

Carl R. Wolf, President

Carl R. Wolf is President of Service Unlimited, Inc. In 1962, Service Unlimited was incorporated through a partnership between Carl’s father, Richard (Dick) Wolf and Eugene Gaumer. Carl attended Valley Forge Military Academy. While in college, he worked at Service Unlimited during summer school breaks as a sheet metal helper and a service technician helper. Carl graduated from the Military Academy in 1970 and began working full time at Service Unlimited as a Service Coordinator and a Technician Assistant. In 1986, Carl took over full ownership of Service Unlimited, due to the unfortunate passing of his father, Dick Wolf. Carl’s love for the company brought about his re-evaluation of the firm and he implemented a plan to move the company in the direction of providing single source responsibilities covering every technical aspect of mechanical systems. To date, Carl’s "hands on" involvement and engineering expertise have made Service Unlimited, Inc. into one of the most reputable mechanical firms in the Tri-State area.


Ralph Rose
(302) 326-2665

Ralph R. Rose, Vice President - Construction Operations

Ralph Rose has been employed with Service Unlimited, Inc. since 1981. In July of 2009, Ralph was promoted to Vice President of Construction Operations. The loyalty and dedication that a person like Ralph portrays within our firm is highly commendable. The best words to describe Ralph are “detail oriented.” His daily involvement with our design-build construction projects, have reflected just how detailed Ralph is by their award winning results. Ralph is the Father of two lovely daughters, Bethany age 19 who attends Wilmington University and Melanie age 15, who attends St. George’s Technical High School. In Ralph’s spare time, he enjoys being involved with and coaching girl’s fast pitch softball. Ralph will be more than happy to have you reach out to him to talk about HVAC additions, upgrades or design build projects that you may be seeking his expertise on.


Brian Martinenza
(302) 326-2665

Brian Martinenza, Jr., Vice President and General Manager

Brian Martinenza, Jr. has been employed with Service Unlimited, Inc. since completing his Bachelor’s degree in Business Administration and Economics at McDaniel College in 2004. His experience within Service Unlimited has been varied and includes time spent throughout the service department. Brian worked in the field full-time as a Service Technician completing his four (4) year apprenticeship in 2009 and is recognized as qualified Journeyperson in HVAC by the State of Delaware. Many of our customers have had the pleasure of meeting him while he worked in this capacity or in his role as Operations Manager to which he was promoted in 2010. Brian embraced this role will vigor and focused his efforts on reemphasizing customer service, and employee development. In January 2012, Brian was again recognized for his contributions to the company with a promotion to Vice President of Operations. He will be working to ensure solid growth and development in all phases of the company. Improvements in training, communication, and an overall standard of quality are goals he hopes will guide SUI through its 50th anniversary. Brian is married with 3 children and currently resides in Newark, DE. He enjoys Philadelphia sports, DIY projects, and spending time with his family.


Jeff Stimmel
(302) 326-2665

Jeff Stimmel, Service Sales Coordinator

Jeff Stimmel started with Service Unlimited, Inc. as a Service Technician in the year 2000. In 2002, he moved into the offices to work in the Service Department. In July of 2009, Jeff was promoted to be our Service Operations Manager, which means having his “fingers on the pulse” of every move we make in servicing our Customers. Prior to joining our Service Unlimited team, Jeff worked as a Maintenance Mechanic for Westvaco Corporation for 17 years. Jeff enjoys playing as hard as he works and enjoys boating, fishing, the beach and sports.


Ryan O'Hara
(302) 326-2665

Ryan O’Hara, Technical Sales Associate

Ryan O'Hara started with Service Unlimited in September 2011. Before joining our team, Ryan earned his Bachelor's Degree from East Carolina University in 2004. He returned home to the Baltimore area after graduation and began his HVAC apprenticeship. Ryan relocated to Delaware in 2008 where he honed his HVAC skills as a technician and eventually a salesman for a large HVAC company.

In his role as Technical Sales Associate, Ryan is excited for the opportunity to sell preventative maintenance service agreements, retrofit and replacement equipment, and to provide support to customers with new installation opportunities. Ryan is an active member of Crossfit Riverfront, the ABC of Delaware, and the New Castle County Chamber of Commerce. In his personal time, he enjoys watching the Baltimore Ravens and working on his home improvement projects.


(302) 326-2665

Jamie Kreider, Customer Service Coordinator

Jamie started with Service Unlimited January 2013. She is currently studying Psychology and Mathematics at Wilmington University with honors. Jamie has 10 years of experience with customer service and sharpened her dispatching skills at a large heating and cooling company. In her free time she enjoys painting, snowboarding, and playing music.

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