on hrv, there are two buttons, to set the hrv in a testing mode, which will keep the hrv running. turn off your furnace, and press that button, the hrv/furnace should stop.
i had the same issue when i first day get the new house, and tested out the furnace on/off button. it didn't work so I called harding (the company who installed furnaces for lots of builders in ottawa). they sent in a guy with in 30 minutes, found out the guy who tested my hrv didn't put the hrv in normal mode back.
把furnace的控制开关(一楼的)关了: you mean put the fan in off mode on your hemostat, not turning off the power of your furnace (in basement). if you turned off the power and furnace fan still blowing, you might find a new way to save energy cost for you home
if it is a new house, you may be eligible to a free orientation meeting from the furnace dealer. it will teach you how to control the HRV and the furnace.