Passanger footwell dash?

Hi guys I have a 2003 td5 and I have an odd noise in the passanger footwell. If I lie on my back and look up under the dash there is a plug in port and a circle cut out with a plastic circle sump looking thing under there, it seems be be coming from this!? What is this please!? Thanks in advance

fan for the heater!?, has it gone dry, give it a big skirt of wd40 or summat

Exellent I'll sort that tomorrow

You can get leaves inside the fan and this will cause noises. Easy to remove and check if a bit fiddley.
Griff