McAlpine swivel p trap

[diy_fun_uk]

I'm planning to buy this:

McAlpine Swivel P Trap White 40mm - Screwfix

Order online at Screwfix.com. Polypropylene, rubber and brass construction. Compression fitting outlets. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

If I then want to attach a 40mm section of pipe to the vertical outlet using compression, am I right in thinking I need to buy this to fit into the p trap vertical outlet?:

McAlpine S31U Compression & BSP Connections Straight Connector White 40mm x 40mm - Screwfix

Order online at Screwfix.com. For use with Macvalve-2. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

 

[terryplumb]

Vertical outlet ?? Do you mean the top of the trap that would connect to the sink waste?
Not sure exactly what you are trying to achieve ,but I doubt the s31 will be any use.

 

[diy_fun_uk]

Vertical outlet ?? Do you mean the top of the trap that would connect to the sink waste?
Not sure exactly what you are trying to achieve ,but I doubt the s31 will be any use.

It's for a washing machine waste. I was going to buy this:

McAlpine Standpipe Appliance Trap White 40mm - Screwfix

Order online at Screwfix.com. Constructed from high temperature polypropylene with compression outlets. Suitable for domestic appliances. Multi-fit compression outlet suits waste pipes to BS EN 1451-1-2000. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

But I'm going to have the top of the vertical pipe completely sealed with this:

FloPlast Hose Connector 40mm - Screwfix

Order online at Screwfix.com. White, high temperature polypropylene trap with compression type outlets that fit plastic waste pipes to BS 5254 and BS 5255, copper waste pipes to BS 659 and BS 2871 and 40mm / 1½". FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

So I'm intending to buy the p trap with the anti siphon instead, which doesn't come with the vertical section of pipe included.

 

[terryplumb]

Why don't you just buy a p trap with a combined appliance waste spigot ?
If you prefer to use a standpipe and trap ,it doesn't need to be sealed at the top

 

[diy_fun_uk]

Why don't you just buy a p trap with a combined appliance waste spigot ?
If you prefer to use a standpipe and trap ,it doesn't need to be sealed at the top

I'm moving away from the setup with the combined spigot as there are issues with the washing machine draining that I suspect are being caused by this. I need/want the top of the standpipe sealed to ensure no risk of overflow (too long a story) so I'm thinking (hopefully correctly) that it's best to have the p trap with anti-siphon in case air's needed.

Because this trap doesn't come with the standpipe, I suspect I maybe need that straight connector to attach the standpipe?

 

[terryplumb]

The standpipe comes with its own trap ,from which you connect 40 mm waste pipework to external ,or internal drainage as applicable.
You do not connect the standpipe to the trap that connects to the sink.
The standpipe needs an air break and doesn't get sealed by the way.

 

[diy_fun_uk]

The standpipe comes with its own trap ,from which you connect 40 mm waste pipework to external ,or internal drainage as applicable.
You do not connect the standpipe to the trap that connects to the sink.
The standpipe needs an air break and doesn't get sealed by the way.

I think we're slightly at crossed wires. If I'm looking at the product correctly, the p trap with anti-siphon that I've linked to in my opening post doesn't come with a standpipe, hence me needing to connect a section of pipe to it to act as the downpipe. I'm not intending to connect this to a trap that connects to the sink, again too long a story. Re: the standpipe needing an air break, I was hoping (maybe wrongly) that the anti-siphon feature of the p trap would ensure air intake as/when required?

I could always fit something like this to the standpipe (has air inlet) but ideally I want it sealed at the top so no water can backup and overflow.

McAlpine Twin Hose Connector 40mm - Screwfix

Order online at Screwfix.com. For plumbing 2 domestic appliance discharge hoses into a standpipe trap. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

 

[terryplumb]

Sorry ,I have no idea what you are trying to achieve. You don't want a standalone standpipe and trap ,totally independent. And you don't want to connect the appliance waste pipe into a p trap with an appliance inlet spigot.
So anything other than the 2 options above is some convoluted lash up that you are dreaming up, and quite frankly I just don't get it.

 

[Exedon]

When we fit traps for commercial glass washers and smaller commercial dish washers we use hep v0 traps with a strait adaptor and short length of pipe
Because of design of trap no backflow can happen also works as anti vac trap.

 

[diy_fun_uk]

Sorry ,I have no idea what you are trying to achieve. You don't want a standalone standpipe and trap ,totally independent. And you don't want to connect the appliance waste pipe into a p trap with an appliance inlet spigot.
So anything other than the 2 options above is some convoluted lash up that you are dreaming up, and quite frankly I just don't get it.

To a degree you might be right

See the following pic. At present there's a 1.5 sink waste kit fitted, you can also see where the washing machine waste is fitted. I want to leave all this in place and blank off the existing spigot where the washing machine currently drains to. Beyond the p trap (pic doesn't show it that well) there's a few inches of horizontal pipework where water then drains behind the back wall of the cabinet. I want to install a swept tee at that section, with a horizontal section of pipe then going off to the right as you look at the pic i.e. running along the back wall of the cabinet. I then want to install the washing machine standpipe and trap to this section of pipe. The rationale is the sinks will essentially drain as they do now, however the washing machine will drain into its own more traditional downpipe.

 

[terryplumb]

Unless the pipe that you intend to join into runs horizontally at a lower level than the bottom of the existing trap ,there is no chance of fitting a standpipe and trap.

 

[diy_fun_uk]

Unless the pipe that you intend to join into runs horizontally at a lower level than the bottom of the existing trap ,there is no chance of fitting a standpipe and trap.

I know it's not recommended (2 p traps) however the p trap for the washing machine will be located at the same height as the existing p trap. The water from the washing machine will be pumped down the new downpipe, through the new p trap (with anti siphon) and along the new horizontal section of pipe that will run along the back wall and connect into the swept tee that will be located in front of the hole you see at the back wall. In terms of water flow, I don't see why that wouldn't work? The water from the washing machine isn't being routed through the existing p trap, it only routes through the new p trap before exiting. Similarly, the sink water only drains through the existing p trap, it doesn't go anywhere near the washing machine trap.

 

[terryplumb]

Go for it ,if it doesn't work you can always put it back the way it was.....what could possibly go wrong ?

 

[diy_fun_uk]

Go for it ,if it doesn't work you can always put it back the way it was.....what could possibly go wrong ?

Yeah I know ideally rip it all out and run everything through one trap, however I'm hoping this 'extension' approach will work and save the complete overhaul. I'll be sure to update this thread

 

[diy_fun_uk]

I won't mention that I considered using push fit ...