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Parts for Frigidaire LFFH2067DW1 Freezer - AppliancePartsPros.com

Is the evaporator/freezer fan on when the door switch is held closed?
If the fan is not working the warm air will rise in the cabinet.

Is the compressor on?
You can usually hear it but should also be able to feel it vibrating?
If on is it cycling normally or is it on all the time?

If it is on remove the cover in the freezer to inspect the evaporator coils.

If they are heavily frosted/iced over you may have a defrost problem.
The compressor will probably run all the time except when it goes through a defrost cycle.

If there is just frost in one area (usually where the freon enters the coils) it could be a sealed system problem. The compressor will also run all the time.

I am not sure what the bumping noise is.
Sometimes if there is a mechanical problem with the compressor there will be a bang when the compressor shuts off.
May just be a bad compressor mount so I would check them.