DFUs of a Sewage Pump?

So you want to figure what size pump you need based on how many fixtures the pump will be handling?

No, like if you have a pump with a 2" discharge and it pumps ___ GPM what would the DFU load be from it?

This is from the UPC not IPC but may help

710.5 Building drains or building sewers receiving
discharge from any pump or ejector shall be
adequately sized to prevent overloading. Two (2)
fixture units shall be allowed for each gallon per
minute (3.78 Lim)
of flow.

knuckles said:

This is from the UPC not IPC but may help 710.5 Building drains or building sewers receiving discharge from any pump or ejector shall be adequately sized to prevent overloading. Two (2) fixture units shall be allowed for each gallon per minute (3.78 Lim) of flow.

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Thanks bud. I thought it was 2 DFUs for each GPM I wonder why this wouldn't be in the Our code book?

UPC also has a minimum GPM of 20.

710.3' A sewage ejector or sewage pump receiving
the discharge of water closets or urinals:
710.3.1 Shall'have a discharge capacity of not
less than 20 ga]]ons per minute (75.7 L/m).

I have always just tied into a 4 inch line unless its over 100 gpm

Yeah thanks, I just wanted to be able to figure out the DFUs for ref.

The code gives you a minimum. It's a good idea to look at the manufacturer's performance curves for their various pumps. If your head dictates a pump larger than that prescribed by code, than so be it.

709.3 Values for continuous and semicontinuous flow. Drainage fixture unit values for continuous and semicontinuous flow into a drainage system shall be computed on the basis that 1 gpm ( 0.06 L/s) of flow is equivalent to two fixture units.

From IPC

Ghostmaker said:

709.3 Values for continuous and semicontinuous flow. Drainage fixture unit values for continuous and semicontinuous flow into a drainage system shall be computed on the basis that 1 gpm ( 0.06 L/s) of flow is equivalent to two fixture units. From IPC

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Thanks! That's 709.3 in the. Michigan code also. I Appreciate you finding that.

Plan on tying the pump to a 4 inch drain in residential. The wye has to be on its back and 10 foot away from fixtures and base of stacks if horizontal. You also will need a 2 inch vent off your building drain because you now have a minimal size of 4 inch main sewer....

The vent from the grinder does not count as your 2 inch vent. It also does not fall under the 40 foot rule they use a different chart.

Thats what we look for here under IPC..

ibeplumber said:

I need help sizing a sewage pump DFUs? Michigan Plumbing Code which is basically IPC its not in our code book as far as I can see. I know it's based on GPM but looking for a refresher. Thanks.

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If you found anything let me know. I just failed my residential plumbing test because I didn't know how to calculate for it.

pruittts17 said:

If you found anything let me know. I just failed my residential plumbing test because I didn't know how to calculate for it.

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9 years later……………….

So happy you failed.