Pentek Big Blue Filter O-ring Replacement: A Quick Guide (Everything You Need to Know)

Okay, so, I’ve been dealing with this leaky water filter situation at home. It’s one of those Pentek Big Blue whole house filters, the big boy. Thing is, it started dripping, slowly at first, and then it got worse. I figured it had to be the o-ring, right? That’s the usual suspect in these cases.

So, I rolled up my sleeves and got to work. First, I turned off the main water supply. No one wants a surprise shower, especially not from a filter. Then, I got my wrench and unscrewed the filter housing. It was a bit of a workout, not gonna lie. Those things can be tight!

Once I got the housing off, I could see the old o-ring. It looked, well, pretty worn out. Flat in some spots, kinda brittle. It had definitely seen better days. Now, I had ordered a pack of replacement o-rings online. I made sure they were the right ones, the 151122 model, specifically for the Pentek Big Blue filters. I read somewhere that you need to replace them every couple of filter changes anyway, so it was time.

The O-ring Replacement:

• Pulled Out the Old O-ring: This was easy enough, it just slipped right out of its groove.
• Cleaned the Groove: I wiped down the groove where the o-ring sits with a clean cloth, making sure there wasn’t any gunk or debris that could mess with the seal.
• Lubed Up the New O-ring: The new o-ring came out of the pack, and I could tell it was good quality rubber. I put a little bit of food-grade silicone grease on it – just a thin layer. This helps it slide into place and makes for a better seal.
• Placed the New O-ring: I carefully placed the new o-ring into the groove, making sure it was seated properly all the way around. No twists or kinks.
• Screwed the Housing Back On: Then, it was just a matter of screwing the housing back onto the filter head. I tightened it by hand first, and then gave it a final snug with the wrench. Not too tight, just enough to make sure it was secure.

Finally, I turned the water back on, crossed my fingers, and watched. No drips! Success! It’s been a few days now, and it’s still holding strong. I’m pretty happy with myself, to be honest. Saved myself a plumber’s bill and learned something new in the process. It’s not rocket science, but it’s satisfying to fix something yourself, you know?

So, yeah, that’s my little adventure with the Pentek Big Blue filter o-ring. If you’ve got one of these filters and it starts leaking, don’t panic. It’s probably just the o-ring, and it’s a pretty easy fix. Just make sure you get the right replacement part, and you’ll be good to go. I also learned that our Compact Whole House Filters could use these, too.