Why does a fridge freezer fail an insulation Pat test?

[Nwpattesting]

Hi, I am getting a reading of 0.00MOhm
I've never had this before, it's not tripping the rcd.

I was wondering if it may be damp but can't see anything obvious.

Any ideas please?
It's not very old.

 

[brianmoooore]

Had one once where the heat from the interior lamp was melting ice (that had formed where it shouldn't have) when the door was opened, the liquid ran down onto live parts near earthed metal and tripped the RCD a minute or so later. Water then froze again, so IR was good again when tested.