Sand filter question

[opsh8r]

I purchased a house last year, and it came with a pool. Prior to this I have zero experience with a pool, and I am still learning about how it operates. It came with a cartridge filter setup. For her birthday my girlfriend wants to switch to a sand filter to keep from having to disassemble the filter tank and clean the filters regularly. I understand that the cartridge filters will do a better job of cleaning the water, but the girlfriend usually gets what she wants.

I have an approximately 15,000 gallon pool with a spa and a Polaris cleaner. The pool pump is an older Pentair 2 HP. It, along with the pool, is approximately 10 to 12 years old. I had the impeller replaced last year. Also, the piping is 2".

I was originally looking at a Hayward S244S side mount filter. Having done some research, and talking to one of the national pool supply companies, this size filter is probably too small for the pool pump. They tried to upsell me to a Hayward S310S. This filter is quite a bit more (about $700 plus sand) than the price range I'm wanting to spend in. I'm curious if anyone can tell me if a Hayward S270 would be adequate based on my pump size. It's a little more costly than a S244, but much closer to my price range, and I would save also on the reduced amount of sand I would have to purchase. One downside to the S270 is that it only comes with a top valve. Currently my filter is plumbed for bottom valves, so I would have to change that, but it would be much cheaper than buying a S310. The S270 has a 78 GPM rate, which is about halfway between the S244 and S310 flow rate. I'm thinking that due to its age my pump probably isn't as efficient as it was new, which would help bridge the gap with the GPM rate between my pump and the filter I'm wanting to purchase.

I'm also willing to look at other manufacturers, as long as they produce quality products, and I'm also not wanting to save $200 today to have to spend $500 in 6 months because the pump was damaged due to the flow rates being incompatible. I am not the most handy with tools, so the money I save on the cost of a filter could pay for having someone install it. Thank you all in advance for your time.

Paul

 

[duraleigh]

What the forum suggests comparing is the flow rate of the pump and filter.

Generally, it is a good rule to have a filter that exceeds your pumps gpm by about 25%. In short, a slightly over sized filter.

The most misleading part of being able to do that easily is the pump's true capacity. A 1.5 hp full rated pump is the same as a 2 hp uprated pump. Probably the best way to work around that is to find the "pump curve" on the manufacturer's website and you can get a good idea of the flow for the pump then match your filter to that.

I am not completely sure of this but I think a constant speed pump loses little efficiency over time so you can use the published pump curve.

A particular brand does not seem to make much difference.

 

[JVTrain]

I have a 30000 gallon in ground pool. I chose to go with a 27 inch sand, 350 lb., with a top mount valve. The reasons I chose it were:
1 - We have a short pool season here. 5 months on average, 6 months if you count the kids' willingness to withstand the cold water.
2 - Water is cheap. My filter is undersized which means more backwashing but water here is cheap. I just have to worry about keeping an eye on CYA a bit more often.
3 - I was willing to replumb the filter myself. The old (even more undersized) sand filter was a side mount valve. Replumbing was a bit of a headache (and I still have to add a union I forgot to add) but I got to redo it right with rigid plumbing instead of the old flexible PVC.
4 - My pump is a 1 HP.

EDIT:
5 - It was quite a bit cheaper than the 31" and the largest filter my pad could accommodate between the heater and pump was the 27".