Best pentek big blue 3/4 inch npt filter replacement: Comparing top choices for your water filter!

Okay, here’s my story about replacing the Pentek Big Blue 3/4 inch NPT filter.

So, the water at my place started tasting a bit off. You know, not terrible, but just not as crisp and clean as it used to be. Figured it was time to swap out the water filter. I’ve got this Pentek Big Blue whole-house filter, the one with the 3/4 inch NPT connections.

First things first, I turned off the main water supply to the house. Don’t want any surprise showers while I’m working on this thing. Then, I grabbed my trusty filter wrench – you know, the big plastic one that fits around the filter housing. Had to wrestle with it a bit, these things can get pretty snug, but eventually, I got the housing unscrewed.

Inside, there was the old filter cartridge. Looked pretty gunked up, definitely did its job. I pulled that out and gave the inside of the housing a quick wipe down. Just wanted to make sure there wasn’t any loose sediment or anything hanging around in there.

Turn off the main water supply.
Use the filter wrench to loosen and remove the filter housing.
Remove the old filter cartridge.

Replacing with the New

Now, for the new filter. I picked up a Pentek RFC-20BB, which is a 20-inch radial flow carbon filter. It is just a big block of activated carbon. I unwrapped it and popped it into the housing, making sure it was seated properly.

Before screwing the housing back on, I checked the O-ring. It’s this big rubber ring that creates a seal between the housing and the cap. I heard somewhere that you are supposed to replace this thing like every third time you change the filter, just to prevent leaks. Mine looked okay, so I just put a little bit of food-grade silicone grease on it to keep it in good shape, and called it a day.

Then, I screwed the housing back onto the cap. I hand-tightened it at first, and then gave it a little extra nudge with the wrench. You don’t want to overtighten these things, or you could crack the housing.

Insert the new Pentek RFC-20BB filter into the housing.
Inspect the O-ring and apply silicone grease.
Screw the housing back onto the cap, hand-tighten, then slightly tighten with the wrench.

Finally, I slowly turned the water back on, keeping an eye out for any leaks. All good! I let the water run for a few minutes to flush out any loose carbon from the new filter, and that’s it. Water’s tasting great again. A pretty straightforward job, even for someone like me who’s not exactly a plumbing expert. And my Pentek filter, the 3/4 #10 blue one about 10 inches long, is working like new again.

It wasn’t hard to do and I was