Denso Air Conditioner Error Code TANK

The TANK error on a Denso air conditioner means the internal condensate drain tank is full. The unit collects moisture removed from the air during cooling in this onboard tank, and when it reaches capacity, a float-activated switch shuts the unit off to prevent overflow. The full tank LED will flash on the control panel to confirm this condition.

No. The unit automatically shuts itself off when the TANK error triggers, and you should not attempt to bypass this shutoff. Running the unit with a full drain tank risks water overflow, which can damage flooring, nearby equipment, or the internal components of the air conditioner itself.

In most cases there is no repair cost at all, since draining the tank is a free maintenance task the owner can perform. If the drain tank switch has failed and requires replacement, parts and labor costs typically range from $50 to $150 depending on part availability and service rates in your area. Recurring errors in low-humidity conditions are the main indicator that a switch replacement may be needed.

Remove or drain the condensate tank, empty it completely, and then firmly reinsert it into the unit. Once the tank is properly seated and no longer full, the drain tank switch will reset and the unit should resume normal operation. If the error returns quickly after draining, inspect the float switch for debris or a stuck position.

A simple power reset will not clear the TANK error because the drain tank float switch remains activated as long as the tank is full. The tank must be physically emptied and correctly reseated before the switch resets and the error clears. Only after draining the tank will the unit be able to restart.