Latest Discussions : Plumbing


04:44PM | 12/02/05
Member Since: 04/25/05
1915 lifetime posts
How fast do clothes washer discharge water?

The washer will discharge into a basin pump which inturn will pump it up about 6 ft to sewer level.

The basin pump has a 10 gal holding tank and will pump about 2000 GPH (33 GPM). It only has a 1 1/2" inlet and discharge.

I am wonder if this will keep up with the washer or if I should install a laundry tub so that an excess can backup in the laundry tub.

Cross posted to appliances.


01:37PM | 12/06/05
Member Since: 01/30/05
360 lifetime posts

Not sure what code(s) apply in your jurisdiction, nor "where in the world you are",but the IRC (international residential code) requires a 2" discharge from a washing machine, UNLESS you are first discharging into a laundry tub..then you could get by with a 1-1/2" intake port on your pump. First thing to do is to contact your AHJ and determine what code(s) are in effect in your locale, which version, and what if any local amendments have been made to same.

Said "horizontal" 1-1/2 drain line from laundry tub is further limited to distance and/or pitch to "pump".

Obviously said "basin pump" is not designed, nor qualified to afford direct washing machine discharge (kind of a clue when you call it a "basin pump"). You don't specify, but I'll take a wild guess and also persume that said "basin pump" has a 2" vent.

To be a true sewage ejector pump (not just a water removal system) which would be required, it must have a "macerator grinder" in order to allow less than a 2" discharge line, so said pump would not qualify for use in either a direct from washing machine or a pump from a laundry tub before the washing machine discharge application.

additional required specifications (per the IRC):

1. water tight receptor

2. water tight removable service cover

3. minimum 14.6 GPM discharge

4. 2" intake port, unless the washing machine discharges into a laundry tub first, and then the laundry tub discharges to this pump...then a 1-1/2" intake port is permitted.

5. The intake port lowest input level must be 2" above the pump start level.

6. a minimum 2" discharge line, except pumps equiped with a "macerator grinder" where then it can be a 1-1/4" discharge line.

7. There MUST BE a checkvalve on the vertical discharge line and a manual "gate valve" or "ball valve" may or may not be required above the required check valve.

8. The discharge line must rise vertically to a point ABOVE the gravity flow line to which it discharges.

9. The pump discharge must be connected to the gravity flow line by means of a Wye fitting with the side opening on top of the pipe.

10. The gravity flow line receiving the discharge must be sized at 1.5 DFU for each gal/min discharge from the pump.

The maximum permissible DFU load on a 3" horizontal house main drain or house sewer line with a 1/4" per foot pitch is 42 DFU.

11. This pump may well require its own auxillary vent through the roof. If the overal length of said vent line is 40 foot or more it is required to be increased one nominal trade size (ex. 1-1/4" to 1-1/2"; or 1-1/2" to 2", etc.).

Are you in a climatic region which is subject to freezing? If so all vent openings through the roof may be required to be increased to a minimum of 3" in diameter INSIDE the structure to prevent frost closure.

You will also need to keep in mind LINT and clog issues regards to modern clothes washers (with self-cleaning pumps) that no longer strain lint from the wash/dishcharge water and make clean-out and lint-catching accomodations for same (to avoid flood-causing clogs).


04:18AM | 12/08/05
Member Since: 04/25/05
1915 lifetime posts
First it is clear that you don't know what a basin pump is?

But although you gave lot of details, none of it answers the question.

How fast do washing machines discharge water.

I gave the pumping rates, will the pump keep up.


06:38AM | 12/08/05
Member Since: 01/30/05
360 lifetime posts
What about the caption did you miss?

This 1-1/2" input and 1-1/2" discharge pump

doesn't qualify for a laundry tub basin pump by either national plumbing code.

Furthermore it doesn't qualify for a direct discharge from a washing machine.

If it doesn't have a "grinder" you cannot legally use it as a laundry sink discharge.

The devil is in the details, obviously above your head.

I am VERY familiar with such issues.

you, OBVIOUSLY are not.

UNLESS you have a grinder, you must have a pump with a 2" discharge for the sink - get it? got it?

If you're looking for a pump for a direct laundry machine stack/discharge, it must have a 2" input and a 2"+ discharge. Get it? got it?

Obviously reading, spelling and clear thinking are beyond you!


04:41PM | 12/09/05
Member Since: 12/09/03
175 lifetime posts
I goofed on my click. I left an answer to help with your problem. C.


05:32PM | 12/09/05
Member Since: 04/25/05
1915 lifetime posts
Thanks for the HELPFUL reply.

erik peterson

08:04AM | 12/11/05
Member Since: 06/23/03
223 lifetime posts
Ive seen this repulsive/off-putting person on other sites....hopefully he/she will stay off this venue............erik


07:55PM | 12/21/05
Member Since: 01/30/05
360 lifetime posts

1-1/2" opening and outlet enjoy the premature death of your washing machine and lots of future mop ups. if you had a CLUE you'd realize that despite the power of the pump you are restricted to the DFU potential of 1-1/2" line. furthermore you'll see they always rate their "systems" in gph not gpm. Finally - they are NOT suitable as ejection systems, do NOT qualify for same, and if you bothered to go further than the limited p-trap for a laundry tub you'd realize that.

Sure hope you aren't planing on using any detergent in your washing machine if you're going to throw in a WRS which ever model.

even if a 1-1/2 input would satisfy, the 1-1/2 output restriction WILL NOT. Sure hope you don't mind a 5-gallon bucket of BIOSLIME..because you'll have a glob, right quick.

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