Hello from the frozen (well thawing) north,
Have been planning for a 20x40 rectangular inground with 8.5 ft deep end, and this is a summary of what I’ve read here about installing suction points other than the skimmers. The contestants:
Main Drain -
Good: Can completely drain the pool to change liners (but that’s what, every 10 years? Easy enough to throw in a submersible pump every decade). Can drop the water level for winterizing, chemistry issues, and some repairs (not absolutely necessary, but convenient). Helps with deep end circulation (though returns work better). Can save the pump if water inadvertently drops below skimmers (this can also be accomplished other ways including an automatic filler).
Bad: Adds cost and complexity to install and repair, two more liner penetrations/leak possibility, and can “rob” suction from skimmers which are more important. MD’s don’t seem to do anything that can’t be done fairly easily or better by something else.
Low Suction through a Wall -
Similar to main drain, simpler installation, but can’t completely empty the pool.
Equalizer Pipe to Pool from Skimmer -
Good: Low-water pump protection, ability to drop water level for winterizing and some repairs.
Bad: Another liner penetration, ???
Skimmers Only –
Good: Simplest install, no liner penetrations.
Bad: No low-water pump protection (can use auto fill), need to schlep portable pumps and hoses to drop water level once or twice a year.
I didn’t include entrapment risk, assuming that for new construction compliant dual main drains or low suctions would be installed. And I didn’t include the option of piping the main drain to the skimmer, as it didn’t seem like a great choice.
I’m leaning toward installing an equalizer pipe, though I understand they are going out of fashion.
Please let me know what I’m overlooking!
Thanks, John
Have been planning for a 20x40 rectangular inground with 8.5 ft deep end, and this is a summary of what I’ve read here about installing suction points other than the skimmers. The contestants:
Main Drain -
Good: Can completely drain the pool to change liners (but that’s what, every 10 years? Easy enough to throw in a submersible pump every decade). Can drop the water level for winterizing, chemistry issues, and some repairs (not absolutely necessary, but convenient). Helps with deep end circulation (though returns work better). Can save the pump if water inadvertently drops below skimmers (this can also be accomplished other ways including an automatic filler).
Bad: Adds cost and complexity to install and repair, two more liner penetrations/leak possibility, and can “rob” suction from skimmers which are more important. MD’s don’t seem to do anything that can’t be done fairly easily or better by something else.
Low Suction through a Wall -
Similar to main drain, simpler installation, but can’t completely empty the pool.
Equalizer Pipe to Pool from Skimmer -
Good: Low-water pump protection, ability to drop water level for winterizing and some repairs.
Bad: Another liner penetration, ???
Skimmers Only –
Good: Simplest install, no liner penetrations.
Bad: No low-water pump protection (can use auto fill), need to schlep portable pumps and hoses to drop water level once or twice a year.
I didn’t include entrapment risk, assuming that for new construction compliant dual main drains or low suctions would be installed. And I didn’t include the option of piping the main drain to the skimmer, as it didn’t seem like a great choice.
I’m leaning toward installing an equalizer pipe, though I understand they are going out of fashion.
Please let me know what I’m overlooking!
Thanks, John
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