Time to put a mic in various places and compare the sounds afterwards. Say a night each at each piece of equipment. Keep the record levels constant. Your computer would likely do the job well plus record the events for comparisons, etc..
Unplug the fridge. It'll stay cold overnight (If it doesn't, get a new one. You're throwing money away.)
If you don't hear the thump, it's the fridge.
If you do, it ain't.
It's not the fridge.
There's at least 2 thump/clunk sources.
One sounds to be in the vents, often audible 20-60 sec's after gas valve opens, burners fire.
The other sounds like it could be in the kitchen floor-boards/rafters.
I could likely id the vent-clunk. Dunno what to do about the other.
Willie
Is that second one related to furnace timing, too? The (plastic pipe) exhaust vent for our furnace always 'thumps' a little while after the furnace shuts off and the pipe cools and contracts.
Also maybe condensate drain pump, if you have one...
cheers
Jules
It seems not.
80% furnace vents to typical metal flue.Thx, Willie
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.