Washing Machine Waster - Preferred Option?

Andrew May

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Mar 19, 2010, 7:27:47 AM3/19/10

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There are two common options for connecting a washing machine outlet
hose to the drains:

1) Hook the hose over a vertical stand-pipe

2) Connect the hose directly to a spigot on the sink trap

I can see pros and cons of both methods but is there a 'preferred'
method if both are available?

Andrew

pcb1962

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Mar 19, 2010, 10:07:23 AM3/19/10

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If the trap in the standpipe becomes restricted or blocked you won't
know about it until the machine pumps out all over the floor. If the
sink trap becomes blocked it's much less of a problem, the waste water
will flow up into the sink. For that reason I would prefer the sink
trap option. Having said that, in 30 years that I've been using a
standpipe I have never had a blockage.

d...@gglz.com

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Mar 19, 2010, 10:12:22 AM3/19/10

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> If the trap in the standpipe becomes restricted or blocked you won't
> know about it until the machine pumps out all over the floor. If the
> sink trap becomes blocked it's much less of a problem, the waste water
> will flow up into the sink. For that reason I would prefer the sink
> trap option. Having said that, in 30 years that I've been using a
> standpipe I have never had a blockage.

Additional benefits are that the hot water discharged from a boil wash
will help to clear any food grease deposited in the sink trap, and if
one of either sink or washing machine is infrequently used then the
trap is less likely to dry out.

The kitchen I'm putting in now has 2 sinks, washing machine and
dishwasher - so one appliance will discharge into each sink trap.

NT

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Mar 19, 2010, 10:36:32 AM3/19/10

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Connecting to the sink sometimes causes regular regurgitation, fouling
the sink.

A third method is to connect water-tightly to the low waste pipe,
routing the machine hose to make a smell trap and prevent unintended
draining, or if its not long enough, as is often the case, doing some
of this in rigid plastic. No chance of flooding then, and no
regurgitating in the sink.

NT

sm_jamieson

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Mar 19, 2010, 11:40:33 AM3/19/10

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Well on advice from this group, I did this for a temporary
arrangement, but I may do it permanently when I fit out the new
kitchen. The back of the washing machine had various hose clips that
could be used to hold the U bend, and it also came with a U-shaped bit
of plastic for hanging over a sink. This could also have been used to
form a U shape. You can get a washing machine spigot to fit onto a
plain pipe.
One for the wiki (if not in there already) ?
Cheers,
Simon.

Lobster

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Mar 19, 2010, 2:32:19 PM3/19/10

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pcb1962 wrote:
> On 19 Mar, 11:27, Andrew May <andrew_d_...@hotmail.com> wrote:
>> There are two common options for connecting a washing machine outlet
>> hose to the drains:
>>
>> 1) Hook the hose over a vertical stand-pipe
>>
>> 2) Connect the hose directly to a spigot on the sink trap
>>
>> I can see pros and cons of both methods but is there a 'preferred'
>> method if both are available?

> If the trap in the standpipe becomes restricted or blocked you won't

> know about it until the machine pumps out all over the floor. If the
> sink trap becomes blocked it's much less of a problem, the waste water
> will flow up into the sink. For that reason I would prefer the sink
> trap option. Having said that, in 30 years that I've been using a
> standpipe I have never had a blockage.

Yes I've used both types in various configurations over 25 years, with
both dishwashers and washing machines; but the only problems I've ever
had have been the odd blockage with the spigot type. Agree that if there
ever *was* a problem with a standpipe, it would be much messier!

David

Harry Bloomfield

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Mar 19, 2010, 2:43:46 PM3/19/10

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pcb1962 presented the following explanation :

> If the trap in the standpipe becomes restricted or blocked you won't
> know about it until the machine pumps out all over the floor. If the
> sink trap becomes blocked it's much less of a problem, the waste water
> will flow up into the sink. For that reason I would prefer the sink
> trap option. Having said that, in 30 years that I've been using a
> standpipe I have never had a blockage.

Ours did a month or two back, during the big freeze. It stopped the
dish washer, the washing machine and the sink from emptying in the
utility room with a solid block of ice.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

Michael Chare

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Mar 19, 2010, 2:51:15 PM3/19/10

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"pcb1962" <pe...@pandasys.co.uk> wrote in message
news:419f637e-8c75-4da4...@z3g2000yqz.googlegroups.com...

I have a standpipe but never had a trap, nor encountered the need for one.
The water goes down the standpipe, through one right angle bend, through the
wall, another right angle bend and then a short pipe to the drain.

I suspect that if I used the sink drain and it was blocked, the sink would
overflow if the washing machine was left on unattended.

--
Michael Chare

Pete Verdon

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Mar 21, 2010, 5:44:46 AM3/21/10

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Michael Chare wrote:

> I have a standpipe but never had a trap, nor encountered the need for
> one. The water goes down the standpipe, through one right angle bend,
> through the wall, another right angle bend and then a short pipe to the
> drain.

Does this not make a trapless path for sewer gases into your kitchen?

Pete

Roger Mills

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Mar 21, 2010, 6:39:13 AM3/21/10

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In an earlier contribution to this discussion, Pete Verdon

Not if it discharges immediately above a gulley, which itself it trapped.
--
Cheers,
Roger
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