The kotatsu heater unit generates some vibration or blowing sound because some types of products include a motorized fan. Moreover, the thermostat creates a clicking sound periodically. Both cases are normal so you do not need to worry about quality.

Taking a long time to warm up may be caused by the following reasons:

	There is an opening on the edge of the kotatsu futon. The kotatsu futon is not set properly, so the kotatsu thermostat does not work well resulting in low temperatures.
	The temperature is lower than usual. On colder days you may feel not enough warmth with the usual temperature setting. Try setting the temperature a little higher than usual.
	A heater light bulb has burned out. If only cool air comes out after adjusting the temperature controller to the maximum, then it is possible the heater light bulb has burnt out. If this is the case repair and inspection are required, so please contact the distributer you purchased the product from or our company.
	The temperature fuse has burned out or the power cord is broken. If the heater unit does not work, the temperature fuse may have burned out or the power cord may have broken. If this is the case, repair and inspection are required, so please contact the distributer you purchased the product from or our company.