Get cool and stay comfy with 24-hour service from GTK Service. Based in Van Nuys, California, this full-service HVAC company repairs and replaces all residential and commercial heating and air conditioning systems. Call for current specials on American Standard equipment. Visit us www.yellowpages.com … “Van Nuys” California yellowpages “GTK Service Co.” heating “air conditioning” contractors HVAC AC repairs “American Standard” maintenance “home repairs” cooling furnaces …