The final touch: installing an automatic flush

With health and hygiene a key concern for consumers, automatic flushes are becoming increasingly popular, says Jerry Whiteley

I am probably a typical plumber – the jobs at home are always the last ones to get done. However, I recently decided to sort out the downstairs toilet, which had an issue with flushing. The drop valve had become harder to push down and the family was saying, “Don’t we have a plumber?” I bet we’ve all heard that one.

The Roca EM1 touchless flush seemed like the ideal solution for an upgrade.The advantage of installing an automatic flush valve and sensor flush is that the integrated infrared sensor on the flush button detects the movement of your hand without contact.

These types of automatic sensors are becoming ever more popular because they also help avoid bacteria growth and spreading viruses. Many manufacturers are now making taps and other components suitable for the domestic market as demand grows.

1 Preparation

To get started, I turned off the water supply to the cistern – via its service valve – disconnected the pipe and removed the lid and screws holding back the cistern. I had used non-rusting screws, which made this process much easier.

Removing the cistern via the coupling bolts was simple as they hadn’t corroded. I then emptied out the remaining water and used an old towel to protect the toilet seat, placing the cistern on its back, ready to remove the existing drop valve.

2 All change

Changing over the drop valve for the new one was straightforward. Once the old one was out, I cleaned the surfaces of any grit etc. then cleaned off the metal clamping plate.

Always be careful not to over tighten the locking nut when fitting the drop valve and clamping plate. Like any plastic nut, it strips the thread and has to be thrown away and replaced with a new part.

I replaced the seal ring because you tend to find the old one has either lost its compression, become split or perished. If you don’t, then you might well be taking the cistern off again to do it sooner than you imagined.

3 Final fix

Re-assembling the cistern back on to the pan and connecting the water back on, ready for testing with a manual flush, helps to check for those minor drips that might not show up on the first flush or two, as the sealing ring compresses from being bolted together in between the pan and cistern.

I removed the existing chrome push button from the cistern lid, which needed to be a 40mm hole to match up with the new one. The battery pack, found at the top of the overflow tube, holds four AAA batteries and should work for at least 40,000 flushes.

I then inserted the batteries and connected the two cables (red and black), simply pushing/screwing them into their corresponding connections at the top of the new valve. The button still retains the ability to flush manually in case the batteries fail.

The usual plastic push rod underneath needed cutting to length to allow a manual flush operation, should it be necessary. The water usage of the flush can be adjusted from 6/4, 4.5/3 or 4/2 litres accordingly, which can help save on annual household water usage.

4 Job done

The whole job took me around 45 minutes. I know that not all cistern removals are simple, as access can be awkward, water might not completely turn off, float valves can be easily cross threaded and screws or bolts heavily corroded. Experienced plumbers will know to go prepared with spares and deal with potential problems.