automatic flushing - men's urinals

Working in a school, I think the sustem you nedd is a dual system - activated by motion sensor but also by a long term timer so that the system is flushed once every few hours even if it is not used. I have been told that it is not a good idea to leave the system not flushed for days at a time

Malcolm

Well only making the gents urinal flush when the wash hand basin is used certainly will save you some water! It is probably the ultimate water saving feature.

However the system you are thinking about is called Cystermiser. I believe that it operates on pressure. You will have to Google for it as have only ever fitted the PIR systems that you refered to.

Cheers

the cisternmiser lets a small amount of water, adjustable, into the cistern when there is a drop in water pressure ie when a tap is opened, and slowly fills up the cistern until it flushes. Easy to fit also.

Easy to fit, but doesn't work very well IMHO. It also assumes that men will wash their hands; not necessarily true. The PIR systems are better but as stated by an other, you need a system that can flush once a day, say, if not used.

".....uses a motion detector...."

What does that use - a microphone to detect the splash, etc ?

Some of the cistermisers have that capability.

I fitted one of these

Peter

Should have been

I saw the final solution to this problem in America. They had small manually operated flush tanks over each urinal. Push button operated. But I've often thought that there's no reason not to install a WC flushing tank, there are some very small one's these days.

But it would only work if the inlet supply was slow and that blokes didn't vandalise it if it wasn't able to flush because it wasn't full. If busy they probably need flushing once per hour.

What about the waterless devices that are around?

Aston Matthews used to have a unrinal in their show room which had a washhand basin in the top. It was flushed by the basin waste. Quite clever I thought, but I've never seen one fitted anywhere.

A simple solenoid and programmable 7 day 1 channel c h timer to shut off the water supply into the flush tank during un-occupied periods would be my favourite. Also adjust the fill rate valve to reduce the frequency of flushes. Do however watch out for being too parsimonious as an underflushed urinal builds up urea crystals in the trap and outflow pipe and is a stinking job to clear out. Push-fit joints can be your friend in this eventuality.

The simplest, and cheapest, is to have a wall push button. Screwfix sell one which can be fitted in bathrooms and toilets (IP66 rated - exterior) and set from 2 mins to 2 hours (not by the user). The push-button can operate a water solenoid valve to the cistern. A cheaper push-button can also be outside the toilet.

I would have a timer to flush the urinals once a day. Set it to 5 or 10 mins. The push-button overrides the timer.

There are user operated mechanical push buttons on each urinal, but very expensive.

A few years ago a local authority architect told me about a new police station that they'd been called back to, to investigate the stinking gents. Architect walks in, turns tap and urinals flush as expected but it turned out that the users did not wash their hands.

Another possibly American solution (as I've only seen them in CostCo stores) is a PIR in each urinal. Flushes while you pee or do they flush when you move away. Anyway you get the idea.

Replace the flushing mechanism with manually operated Prestex Push valves and request that users push after going. This is the usual arrangement in the States and the continent.

I noticed this afternoon that our local community centre has a urinal control system by these people:

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Peter Johnson saying something like:

Dirty pigs.

Perhaps Hendon taught them to piss in the urinal and not on thier hands.