trane A/h plastic drain pan

[anthonyac1]

ive noticed tranes a/h units have a hole between the over flow drain and the main drain leaving the drain pan in the upright position! just curious whats the purpose of the hole? the customer had an over flow switch threaded in to the over flow hole but since it had a little build up near the hole the water had to rise higher than usual to activate the float switch.but due to the hole the water leaked out onto the floor never activating the float switch.

[mark beiser]

The hole is there to give water a path to leak to outside the cabinet if there is a drain problem when the air handler is in the downflow position.
When it is installed in any other position, seal the hole up with some silicon caulk.

I've also found that a lot of the float switches, that screw into the secondary drain opening, don't work well on a lot of air handlers, due to the layout of the holes vs the depth of the drain pan.

[anthonyac1]

The hole is there to give water a path to leak to outside the cabinet if there is a drain problem when the air handler is in the downflow position.
When it is installed in any other position, seal the hole up with some silicon caulk.

I've also found that a lot of the float switches, that screw into the secondary drain opening, don't work well on a lot of air handlers, due to the layout of the holes vs the depth of the drain pan.

Sounds pretty logic to me thanks for the reply.

[gravity]

what he said ^^

[bover]

Silicone works well,old tranes had one in the back too