Pulling my hair out over water pressure

[EternalArianne]

So this all started when the city replaced our water meters. First, my water heater started leaking everywhere (luckily it's under the house so no damage). I figured it was just old, label said 2001. Replaced water heater and everything was fine at first. Then I started noticing water leaking from the TPR valve drain on the water heater. I bought a pressure gauge and put it on my outside spigot, was getting over 160PSI overnight!!! TPR valve trips at 150PSI so that explains it leaking.

I called the city and complained about the pressure increase since the installed the new meters. They blew me off stating any pressure issues are customer responsibility. I suspect the new meters have backflow prevention, causing my now closed system to build up and blew my old water heater in the process.

So I installed a pressure regulator valve and thermal expansion tank, both set for 50PSI. Problem solved, I think, until I check my gauge and it's showing overnight spikes still up over 120PSI !!! What else could it possibly be?!

[EternalArianne]

It's been a few weeks and I haven't noticed any spikes in pressure at the faucets, shower, etc. I'm beginning to think when I leave the gauge on the outside spigot overnight, something is tampering with it.

This gauge has two dials - one for the current pressure and one for the spike. The spike dial is free moving so it's possible wind, bugs, squirrels, etc are messing with it making it seem like crazy high spikes. The dial just stays wherever it's moves to by pressure or external variables since I can move it with my hand as well.

It seems my water pressure issues are finally resolved...