If it is RFI, that may be impossible. If it is powerline noise, an inexpensive noise filter from a car stereo shop, or an "alternator noise filter", applied to the power leads to the fridge may stop it.
If you can grab a second battery to power the VHF, so it is completely isolated from the common power source to the fridge, and isolating it stops the noise, a noise filter will do the job. If there's still noise with a second power supply...RFI is harder to stop.
07-15-2011 10:39 AM
VHF interference from 12V refrigeration
I have noise on my VHF when I transmit from the base, about 12" from the refrigeration circuit breaker, or from the RAM mike if the refrigeration is on. I have no interference when the refrigeration is off, and have no interference with my hand held VHF with the refrigeration on or off.