ServiceMark has more than 65 years of experience and provides heating and air conditioning repair in 12 counties in Delaware, Maryland and Pennsylvania. Our continuously updated, highly trained and skilled workforce is available locally 24/7 – even on holidays. The reason is simple – we stand by to serve you when you need us and convenient for you! Our goal is to achieve 100% customer satisfaction and that’s why we offer a 100% satisfaction guarantee, so people can count on us to deliver on our commitments.