On arrival at a specialty clothing and accessory store in Livermore, California, our technician checked in with IVR and mall management. Notified store manager of arrival. Store reported that while having the front doors open to the store, the store front area would remain cold and the back room would continue to heat up. Technician inspected the thermostats first. Found the t-stat located on one of the sales floor walls. With doors open, the t-stat is taking longer to reach the desired temperatures, while the back room is unaffected by the outdoor temps and continues to heat up. There are no mechanical issues to report. Recommended that store not leave front doors open for extended time.