Pipework for cistern replacement

[Edmund]

Hello everyone!

I'm new to the forum and am in the planning stage of my bathroom renovation part of which will involve replacing the lavatory.

I thought it would be relatively straightforward swap - however, I've discovered that the water inlet and overflow pipe of the new cistern are on opposite sides compared to the current cistern. So, I'll need to be doing a bit of alteration on the pipework. Whilst I'm proficient at the basics I'm not that up to speed with all the piping/connector materials that are around at the moment so:

1. the water inlet piping is 15mm copper, what's the best connector to use to connect this to the plastic threaded tail of the water inlet pipe coming out of the cistern?
2. Similarly, the current overflow piping is 22mm plastic pipe (maybe polypipe?), what's the best connector to connect this to the plastic threaded tail of the overflow pipe from the cistern?

Any thoughts and guidance gratefully received!

Cheers, Ed

 

[Lag1rich]

Hello everyone!

I'm new to the forum and am in the planning stage of my bathroom renovation part of which will involve replacing the lavatory.

I thought it would be relatively straightforward swap - however, I've discovered that the water inlet and overflow pipe of the new cistern are on opposite sides compared to the current cistern. So, I'll need to be doing a bit of alteration on the pipework. Whilst I'm proficient at the basics I'm not that up to speed with all the piping/connector materials that are around at the moment so:

1. the water inlet piping is 15mm copper, what's the best connector to use to connect this to the plastic threaded tail of the water inlet pipe coming out of the cistern?
2. Similarly, the current overflow piping is 22mm plastic pipe (maybe polypipe?), what's the best connector to connect this to the plastic threaded tail of the overflow pipe from the cistern?

Any thoughts and guidance gratefully received!

Cheers, Ed

!) Assumeing its pressure fed, Well as for the feed (inlet) dont worry to much, I would go for a flexy tap connector, spend an extra 20p or so and get one with a service valve on it, it be nut and cone to your inlet pipe (spanner job) then the connector side will connect to your floating valve (inlet) make shure it goes on straight, otherwise you could cross thred the plastic thred on the floating valve.
Dont use a spanner to tighten the connector up,only tighten it hand tight!! that will do the Job.

2) Normally the "threaded tail" comes compleate with plastic 22m compression nut and cone!! If not most plumbers merchanse sell them as spares!! Thanks, Rich

 

[Bernie2]

Err!

The ball valve tail is 1/2" British Standard Pipe Thread usually called BSP or BSPT or 1/2" iron.

If your using copper up to the ball valve, you may need a 1/2" x 15mm swivel elbow if your coming off the cistern at an angle or a 1/2" x 15mm straight if your coming off the cistern straight.

Get the 1/2" red or grey compound washers to suite the fitting. They usually come with the fitting.

Its best to use these, as then you can tighten the fitting onto the ball valve just about a quarter to half a turn more than hand tight. When the water contacts the washer they swell and make the joint tight.

The problem with plastic ball valves is that they can easily cross or strip the threads. So over tightening them when using brass back nuts can be a problem.

Yes! Okay! So, I've done it!

The over flow may not be a problem if its a new cistern. Some of the new ones overflow through the syphon so don't need an overflow pipe.

If it isn't that sort, then you have to take the syphon, ball valve and handle out and reverse them so that the overflow is on the same side as the old cistern.

In point you may find if you reverse it, it comes near enough in the same place as the old cistern.

If the cistern won't reverse, then to alter the pipe without using a flex connector. You would need a swivel elbow as before and a 15mm coupler at least, plus pipe.

Depending on the over flow pipe, to connect to the overflow in the cistern there are various ways.

Some have a back nut, but when you look at the bottom of the overflow pipe coming out of the cistern, its got a bit on the bottom that is unthreaded. When you put the overflow pipe in and tighten the plastic grips the pipe. Use a bit of silicon grease on the threads.

Some other sorts have an olive and some require an overflow adaptor fitting. Depends what sort it is.

 

[Edmund]

Thanks guys. Have got the right fittings and all looks ok.