New pump for an old pool

[matrim72]

Greetings for the Midwest

I had a home here in Joplin, MO, until the big one hit May 2011. I am in the process of rebuilding, and one of the damaged articles was my pool (kidney shaped, roughly 23000 gal)

I have changed my floorplan significantly from what I had before, so I had to move my pool pump & filter. Before it was about 15 feet from the skimmer, and had about 25 feet to the single jet. Now I have put the pump & filter on the opposite side of the pool, which means my intake line is about 65 feet from my skimmer now, with about 15 ft to the jet. I called several companies for quotes, and I was told I needed to upsize my intake line from 1 1/2" to 2", which I did. I had a 1hp pump before, but when I go to the pump head charts, it looks like I need a larger pump (assume 48 gal/min to overturn pool in an 8hr period). However, some of the pool pump recommendations I have received from pool places is still at 1 hp. Does this make sense?

Second, since I am repairing my pool, there are many options for various equipment. I had a sand filter before, but I never felt that it cleaned my pool very well (could be me, since I have never had any real instruction for maintenance). I like the cartridge or DE filters, but the pool places recommend against them because of their cost. I might be picky, but I felt it was too cloudy.

Also, there are miscellaneous equipments like the FROG and salt water systems. I like what I have read about the BBB method, but for comparison, how does it rate against these others? Are they just overpriced, or not effective, or ??? One person swears by salt water, saying it is so much easier to maintain, while another says it is just too expensive ($1k for Chlorinator, and another $600 for the controls). Since I am starting from scratch, I want to start out on the right foot.

Lastly, my house came with the pool, so I had a simple chemical test kit. Only measured pH and total Chlorine. Is that adequate, or do you need the better test kits?

Thank you all so much in advance,

Matt

[PoolDoc]

The first issue is what kind of filter: sand, cartridge, or DE. Sand is the lowest maintenance, but you backwash 0.5 - 1% of your pool water each time you clean the filter. DE gives the clearest water, but is HORRIBLE when you are trying to clean a swamp, and is sort of fussy. Cartridge filters waste little water, but often are plumbed without a backwash valve and the larger cartridges are a pain in the a## to clean. If you get a LARGE sand filter and run water through it slowly, you will get very high clarity. I've been doing this for years, on very large commercial pools. I do NOT recommend a DE filter, if you are the sort of pool owner that has an occasional bout with algae. But, if you are meticulous in your chemistry, then a DE filter can be a good option. However, you have to break them down and cleaning them manually 1x per year -- a very messy process. I've only used the System 3 DE myself, and it worked well, but there may be better options. (Don't get either the sand or cartridge System3 !)

That said, if I personally were putting in a system for a ~25,000 gallon pool, with no special features I'd do ALL of the following.
+ (2) skimmers (1, if no trees or bushes nearby)
+ a maindrain;
+ 2 - 3 returns, as low as possible on the walls.
+ 1.5" home run piping from EACH fixture using S40 PVC bedded in sand or 1/2 washed gravel.
+ All piping at the equipment 2" S-40 PVC
+ System capable of flow with 6 hour equivalent turnover (25,000 / (60 x 6) or 70 GPM
+ Sand filter matched at 13 GPM/sft => 5.4 sft, or 30 filter => Pentair TR-100 30" sand filter
+ 2" PacFab multiport valve
+ Whisperflo WFDS-4 or WFDS-6 (1 or 1.5HP) 2 speed
-- look at F,G & B,C curves:

-- 2 speed timer, allowing startup on high, and switch to low, to avoid priming problems:

Intermatic T10604R Pool/Spa Control Center T106M and T104M @ Amazon
Southwire 55189301 3/4-Inch 6-Feet ULTRA Whip-Pre-Assembled with Wires and Connectors @ Amazon
Leviton 1282 15 Amp, 120/277 Volt, Toggle Double Throw @ Amazon

+ Taylor test kits -- yes, you need them. The Walmart is a subset of the K2006, but has OTO testing, so buy it first, and then get the K-2006:

HTH 6-Way Test Kit @ Walmart
Taylor K2006A (3/4 oz bottles) @ Amazon
Taylor K2006C (2 oz bottles) @ Amazon

+ An SWCG -- I can't really make an informed recommendation, except to suggest that you get the biggest one you can, and TURN IT DOWN. Life is a function of "on-time". We've had good reports on Pentair, Goldline/Hayward and Autopilot models. Jandy models may be OK, but I don't recall seeing much. If you get a plain model (no electronic pool controller), you'll want to check and see if you need a timer. The Pentair units can only be adjusted through 5 steps (20% - 100%) without a controller.
+ I do NOT recommend electronic chemical controls from ANYBODY -- they do NOT work well on outdoor pools.

By the way, BBB was a term that CarlD used to describe a group of ideas I developed, and it's kinda acquired a life of its own. SWCG's weren't common, or very reliable, at the time I first published those ideas. But an SWCG is just a METHOD of adding chlorine, and in my mind, is completely compatible with the BBB ideas I developed.

[matrim72]

PoolDoc,

Thank you for the quick response!

I find myself with more questions. Everything I have seen says plan for an 8hr turnover. You based your calculations on a 6hr turnover. Why is that? Preference?

Second, I have 65 feet of pipe between the skimmer and the pump, but it is almost all horizontal. I think there will be only about a foot of vertical head. Which is more relevant? My gut says the horizontal pipe will not bother the pump (at least once it is primed).

Third. Where did the 13 gpm/sft come from for the sand filter? All the quotes back from pool places put me at the 24" filter, not the 30" one, so I am curious what are the advantages.

Lastly, I need the walmart kit in addition to the taylor kit? What is OTO?

Again thanks for the advice and the wonderful links!

Matt

[PoolDoc]

Horizontal pipe is a problem because of the amount of air it often will contain. "Self-priming" pumps have some capability to deal with air, but not lots. And, what capability they do have is usually lost at low speed. So, it's necassary to start on high, run long enough (15 minutes?) to make sure priming has occurred, and THEN switch to low. Putting swing (not: spring!) check valve inline BEFORE the pump can help, but be CAREFUL to orient the valve properly, make sure it's testable and serviceable (debris can get caught in them), and that it's a good valve.

OTO is the only almost 'bomb-proof' chlorine indicator: if says you have none; you have none, and if your chlorine is VERY high, it will still indicate. It's also cheap.

The DPD-FAS system in the K2006 is MUCH more accurate, but not quite a bomb-proof. What many experienced folks here do, is use OTO for quick daily testing, and DPD-FAS for periodic complete tests.

[matrim72]

I guess I should have been more clear about the horizontal pipe.

Since we were talking about feet of head, what is the conversion of horizontal pipe to feet of head? I think I am probably about +1 foot of vertical head from the level of water in the pool, to the placement of the pump, but its the horizontal run which seems to be dictating pipe size and pump.

I think the chart you posted shows a different "quality" of pump based on which efficiency curve you need to be on, which in turn is based on flow rate (based on pool size), and dynamic feet of head (based on pump placement). Is this interpretation not correct?

[PoolDoc]

I guess I should have been more clear about the horizontal pipe. Since we were talking about feet of head, what is the conversion of horizontal pipe to feet of head?

Static head is not affected by horizontal pipe; only by vertical changes. Dynamic head is not effective by either horizontal or vertical changes, per se; rather it's a function of pipe size, interior surface and total length, regardless of elevation changes.

[mas985]

A WFDS-3 or WFDS-24 should be able to easily turn that pool over in less than 6 hours.