Celina Fire Department sent two trucks and five firefighters this morning to Wendy's restaurant on East Market Street at 6:47 a.m. to check out a haze in the building. It is thought to be a problem with the heating cooling system (HVAC), which has been the source of past concerns. Wendy's management will call in outside HVAC repair. The fire department returned to the station at 7:54 a.m.