★★★★ 205 real customer reviews average rating: 3.8 stars
5 Stars By Larry Reed on 2014-11-12
Packaging makes it look like two smaller o-rings. The o-ring is coiled in the plastic bag, so they may appear to be the wrong size.
This fits perfect in the Pentek Big Blue Heavy Duty 4"x20" filter sumps.
There are reviews stating that it is too big, just make sure you order the o-ring that is meant for your filter.
There are also reviews of people complaining that the o-ring has stretched to a larger size and wont fit when changing the filter.
O-rings expand over time which is why you need to replace them often, sometimes each time you replace the filter, depending on how often you replace filters. For example I have a three stage filter system on the home, first stage is replaced often, every 3 months. 2nd stage every 6 mo, third stage every year. Plan ahead and buy several o-rings at a time. (which is what I do)
By chuck J.
on 2017-03-09 Yep, It's the Right One!
Yep, it's the correct one. A bit of advice on the installation though. Make sure you clean both surfaces that this O-ring is going to contact very thoroughly so the O-ring can do it's job properly. Also, apply some plumbers silicone grease very lightly to any O-ring so it will continue to seat well as you tighten it. Pentek 151122 OR-100 Buna-N O-ring for Big Blue Housings
3 Stars By P. Jones on 2015-03-13
This O ring is designed to go with the Pentek ...
This O ring is designed to go with the Pentek housing but doesn't seem to seat properly in the groove. And, if it's off just a little, the housing leaks and you have to start all over again. It's a mess when you have to install and remove housing more than a few times just to get it right. I've had a few of these and even my plumber buddy felt the design was a bit off. I can understand accomodating some contraction when it gets cold, but this was more than just a little oversized . Needs to be engineered a little more precisely.
4 Stars By Crab on 2017-10-21
Great Replacement Seal
Bought this as a spare part and haven't had to use it yet. It looks and feels like the same manufacturer seal so I am confident this will serve its purpose in the future. Fast shipping and would recommend this product as a replacement for #10 filter housing.
2 Stars By Jerry Hyde on 2017-03-05
I bought this o-ring as a spare for my Big Blue 10" filter. The Big Blue was supplied with a square cross-section o-ring, but the spare is a round cross-section and is too large to fit the o-ring groove in the housing. Maybe I got the wrong one. It has 2 numbers on the label: B0025PZSSM and 101330721.
5 Stars By Railbird on 2017-04-30
The original installer said you can get away with re-using ...
The original installer said you can get away with re-using the old one once or twice. I never had much success with a used one and never had any problems with a new one. For what they cost, install a new one.
5 Stars By Nancy H. on 2017-04-10
Got the job done
Plumber installed an extra thick O-ring in our new filter for no good reason. Husband cut it trying to get filter tight. We needed an OEM o-ring to make sure we had the right one. A light coating of the proper grease and this went on easily with no leaks.
1 Stars By Jon in Staunton VA on 2017-08-21
O-ring i not the same as OEM... ...
O-ring i not the same as OEM...much smaller thickness which led to major seal failure and water everywhere upon my last filter change. Old O-ring is over 9 years old and was quickly put back into service taking care of the problem. Unfortunately, I found this out just after the return window closed. I'll go to my local plumbing supply to match a new one...some things you just can't buy online I guess.
5 Stars By Tex on 2017-10-28
Keep a spare o-ring
Great replacement o-ring for the Pentek Big Blue. It's exactly like the OEM o-ring that comes with the Big Blue. I always keep a few spares on hand.
4 Stars By gmredline on 2015-08-31
Nice but troublesome at times.
These can be sneaky to install. Some fit in my BB20 filter housing like butter. Others are a touch too large and require a lot of lubricant to get them to stay in place. Once installed properly, there are no leaks.
Installing these O-Rings will be the most frustrating part of changing your water filters.