Every now and then, we see messages here from people who haven't yet reached home owner's Nirvana and found the right HVAC contractor. Maybe they don't even know how good it can be to find the right one because other peoples' horror stories make it sound like there *are* no "right" ones.
Earlier this week, I e-mailed my HVAC guy some photos of the filter setup on my furnace. Never mind why, but in the pictures, he also noticed a bucket I'd placed under my water heater's pressure relief valve, and asked what that was about. I explained that it releases some water occasionally, that I'd had the water pressure checked (before and after the regulator) by the water authority, and that I hadn't really focused much attention on the issue much, since the water heater was only 3 years old. His response:
"Even though you're measuring 50-60 lbs of water pressure, it may be creeping up during the off cycles (at night). The pressure/temperature relief valve should be rated for 150 lbs. The only way to know if whether the valve is defective or the pressure is too high is to install a gauge on the water heater spigot which measures the pressure and records the peak reading. I've got one I'd be willing to let you borrow. There's no sense in replacing the relief valve if it's doing its job - ie the pressure really does go above 150 at some point. That may explain the erratic water fill pattern in the bucket. Sometimes the peak pressure above 150 lbs only happens once in a while. If that's the case you'll need to address the pressure problem not the relief valve symptom. There are several fixes for that. I'll share them with you once we figure out the real problem. My experience has been that a safety device that "trips" is usually doing its job. Whether it's a limit switch in a furnace or a pressure valve on a water heater - they usually fail for a reason, not because they are defective.
Anyway, I look forward to you coming in with the filter. I'll be glad to go over that with you. It really is a decent filter and would be a shame to get rid of it. It's not too difficult to change once you get the hang of it."
Whether you agree with his thoughts or not, this is the kind of contractor everyone should have. (His people also do great work)