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Recommended Pump Combinations (duty,standby)

Recommended Pump Combinations (duty,standby)

Recommended Pump Combinations (duty,standby)

(OP)
Hi,
I was wondering what is the most recommended pump combination in the following situations.

1- Underground pump room for a residential swimming pool.
A submersible pump is required for filter backwash, draining the pool...etc.
My current thinking is (duty + 100% standby)

2- Submersible sewage pumps for small basement living quarters (approx 6 people, 3 showers, 3 water closets, 4 washbasins)
A submersible pump is required to lift the toilet sewage up to a manhole of the ground floor.
My current thinking is (duty + 100% standby)


Regards.

RE: Recommended Pump Combinations (duty,standby)

Have you checked out thread407-360540: 2x100% or 3x50% pumps in power plants in this forum for some reading and self education.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Recommended Pump Combinations (duty,standby)

Being residential, probably not more than 1. Just buy relatively good ones. Not more than the best the owner can afford.

I hate Windowz 8!!!!

RE: Recommended Pump Combinations (duty,standby)

All depends how much you need security of working and whether there are any big variations in flow.

Swimming pool, probably fixed flow, hardly a big crisis if it breaks so 1 alone should do.

Sewage, if no sump then variable flow and pretty vital it works all the time (!) so 2 x 100% or 3 x 50%

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Recommended Pump Combinations (duty,standby)

Nobody installs spares on residential pumps as the pumps can typically be purchased off the store shelf.

If the project is located out in the wilderness, consider purchasing an uninstalled spare pump.

Buy a quality cast iron pump, not something made of plastic.

RE: Recommended Pump Combinations (duty,standby)

All depends on what happens in the "small basement living quarters" if the sewage pump fails.... I'd like to have a backup installed. Of course how anyone would know if one of the pumps had failed is another issue, but that's not the thread here.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Recommended Pump Combinations (duty,standby)

10 States Standards require # of required pumps plus one (2x100%) for public sewage lift stations. This wouldn't apply to interior lifts and I am unfamiliar with the plumbing codes.
Duplex pumps also extend the life of the system because of cycling use.
bimr's probably right for residential, but I wouldn't want sewage all over my basement.

RE: Recommended Pump Combinations (duty,standby)

For the sewage unit I would definitely opt for 2x 100% set up to alternate the starting sequence, this could be daily / weekly / monthly cycle.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Recommended Pump Combinations (duty,standby)

(OP)
Artisi,
Thank you for your response. I had already looked at it before I posted this, but what came to my mind was that power plants have different requirements from residences. I also wanted to get an idea what the standard practice was, away from all of the technical jargon and numbers. And I do find what you mention in your second post to be convincing.

BigInch,
Thank you for your response. Noted.

LittleInch,
Thank you for your response. Noted.

bimr,
Thank you for your response. I'm more inclined to agree with what LittleInch says regarding the sewage pump. Just like jgailla said, nobody wants sewage all over their basement.

jgailla,
Thank you for your response.Noted.

RE: Recommended Pump Combinations (duty,standby)

Assuming the basement living quarters are new construction individual apartments/condos, I would probably plan on a separate sewage ejector pump for each water closet/residence that would also handle the shower and washbasin drainage. More expensive up front, but easier to maintain seperate billing accounts and maintenace records. Maybe even keep a single spare pump in the maintenance room for that holiday weekend emergency that always seems to pop up. Residential sewage ejector pumps are not terribly expensive, but the damage from a failure of a single pump with three families using it could be devastating. I can guarantee you, not everyone is going to stop using the toilet just because the pump in the maintenance room stopped working, but if the poop is on your own floor most people will not add more to it.

RE: Recommended Pump Combinations (duty,standby)

One of the reasons that you have so many opinions is your ambiguous posting.

For example, you posted "small" basement living quarters but then post "6 people, 3 showers, 3 water closets, 4 washbasins)". Which is it?

For a small basement, one would recommend a single pump while one might recommend multiple pumps for a large basement because of the inconvenience to 6 people should the system fail.

Buildings are commonly required to have overhead sewers when the drain overflow is below the top of the municipal sanitary manhole in the street because of possible sewer backups from the sanitary sewer. Pumps for these overhead systems usually have failure alarms and may have battery backups.

A single pump with battery backup and alarm is probably a better selection than duplex pumps.

There are also other options that can be considered such as upflush toilets.

You also mention a "manhole" on the "ground" floor which would be quite unusual.



RE: Recommended Pump Combinations (duty,standby)

keyepitts also raises some additional questions that would be best answered by visiting the local municipal building code office.

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