|
|
Post by arfur chrysaik on Apr 7, 2018 19:04:23 GMT
The traditional stop tap had a loose jumper (washer) inside so the incoming supply incoming from beneath would hence be pushing the jumper upwards into the body and allow the mains water in. However, if there is a drop in pressure and some back syphonage occurred the loose jumper would then be pushed downwards and not allow the mains to become contaminated (with the stoptap acting as a rather crude check valve). This was all back in the day. At a more recent WRAS training course the instructor said the there was nothing wrong in having a full bore lever valve on the incoming mains and said it was now the preferred choice. Perhaps with all the new WRAS regulations involving single and double check valves to protect the mains they feel that the old fashioned stop tap (with it's rather crude back pressure protection) is no longer needed. None the less they are still being fitted in new builds! Crowsfoot, no offence to you mate but WRAS have feck all to do with Water Regulations, these are set by the the local authority, WRAS are to do with the plumbing fittings only. years ago it was the water board went round sites checking fittings (taps etc) were up to scratch now they have all joined this pocket lining club which is WRAS. Who in their right mind would pay twice the price for a compression fittings that has "WRAS Approved written on the bag?. |
|
ian
chief spread 
Posts: 294
|
Post by ian on Apr 7, 2018 20:17:26 GMT
jolly good suggestion chaps, Im off to do one now,,,,,,,,,,,,,,,,,,  Just seen the video, you soon got that done! Tha cornt beat that for service! Thanks for the mention  |
|
|
|
Post by tomplum on Apr 7, 2018 20:45:35 GMT
always happy to help Ian, |
|
|
|
Post by crowsfoot on Apr 8, 2018 12:11:04 GMT
The traditional stop tap had a loose jumper (washer) inside so the incoming supply incoming from beneath would hence be pushing the jumper upwards into the body and allow the mains water in. However, if there is a drop in pressure and some back syphonage occurred the loose jumper would then be pushed downwards and not allow the mains to become contaminated (with the stoptap acting as a rather crude check valve). This was all back in the day. At a more recent WRAS training course the instructor said the there was nothing wrong in having a full bore lever valve on the incoming mains and said it was now the preferred choice. Perhaps with all the new WRAS regulations involving single and double check valves to protect the mains they feel that the old fashioned stop tap (with it's rather crude back pressure protection) is no longer needed. None the less they are still being fitted in new builds! Crowsfoot, no offence to you mate but WRAS have feck all to do with Water Regulations, these are set by the the local authority, WRAS are to do with the plumbing fittings only. years ago it was the water board went round sites checking fittings (taps etc) were up to scratch now they have all joined this pocket lining club which is WRAS. Who in their right mind would pay twice the price for a compression fittings that has "WRAS Approved written on the bag?. You're quite right arfur. I've got confused here (rules are for fools  ) A quick check reveals that WRAS (Water Regulations Advisory Scheme) are indeed only the publishers of "The Water Regulations Guide" and would have only been that particular course providers. I thank you for pointing this out to me  . |
|
|
|
Post by crowsfoot on Apr 8, 2018 12:29:18 GMT
I should like to point out that this stop tap acting as a check valve thing was not from any official training course. It was simply the result of a plumbers brew cabin chat many years ago. We were discussing fixing the jumper in the stop tap to help counteract some water hammer when one of the plumbers piped up (pun intended ) that you "should never fix a jumper in a stop tap because it acts as a protection against mains contamination". When we all thought about it made sense and that single plumber won that lunch time debate. I have never come across it before or after that friendly(?) debate* It is something that I've never checked out though and has it's now on my mind I'll make a video ASAP of it and post it up. Tappy, PS *Plumbers meetings and debates at work often lead to a lot of arguments and things can get very heated at times. |
|
|
|
Post by tomplum on Apr 8, 2018 12:55:25 GMT
we were having a meeting similar during a refit in a disabled old persons home, there were 4 plumbers having a dinnertime debate inthe kitchen where we were having lunch/dinner, the debate was about which side the hot should be, Now this was in the 80's when different districts had different rules, 2 plumber were from London and myself and my mate were from Wigan, the job was in Leicester, the London plumbers argued right for hot and we argued right for cold, and both team gave valid reasons why, someone argued that a blind person will always go right for hot and we argued it would depend where he/she lived and it all got a bit shouty and loud, then this guy who was a resisdent in the home shouted out loud from the day room, which was next to the kitchen, I'm blind but I'm not fuckin' stupid, I know if it runs hot to move my hand,to which we all laughed and got back to work,,,  |
|
|
|
Post by arfur chrysaik on Apr 8, 2018 13:58:08 GMT
I'm the same as you Tom was taught hot on left except for the bath which was the tap nearest the wall for kids scalding themselves ( the days of the coal fire - back boiler where the water was sometimes near boiling ), most of todays mixer taps and shower valves come with hot on the left as standard.
|
|
|
|
Post by crowsfoot on Apr 8, 2018 14:59:41 GMT
Or was it because plumbers like to keep the more difficult (to fit) 22mm pipe always the closest to them on a bath ! |
|
|
|
Post by tomplum on Apr 8, 2018 15:05:14 GMT
that makes perfect sense Tappy, |
|
|
|
Post by dickpuller on Apr 8, 2018 20:40:06 GMT
I'm the same as you Tom was taught hot on left except for the bath which was the tap nearest the wall for kids scalding themselves ( the days of the coal fire - back boiler where the water was sometimes near boiling ), most of todays mixer taps and shower valves come with hot on the left as standard. Yup me too mate, now here in Jockoland we fit blending valves as standard, so it’s always hot on the left👍 |
|
|
|
Post by crowsfoot on Apr 9, 2018 19:22:10 GMT
I've just done the stop tap video.
|
|
|
|
Post by tomplum on Apr 9, 2018 20:09:06 GMT
good demo Tappy, It seems the cheap taps of today have forgotten why their design is such, in the words of a famous actor, " not a lot of people know that", |
|
|
|
Post by tomplum on Apr 10, 2018 13:30:14 GMT
Tappy's discovery intrigued me so much that i had a look inside the stoptap in my video, Its a 20mm poly x 15mm stoptap, and it has a semi loose jumper, So it acts as a check valve if you just crack it open, but after 2 turns the jumper is pulled off the seat and its an open valve both ways, I wonder if this is a deliberate thing they have done, or has no one noticed, I certainly did not know till tappy brought it to our notice, any other thoughts,  |
|
|
|
Post by tomplum on Apr 10, 2018 15:12:37 GMT
|
|
|
|
Post by crowsfoot on Apr 10, 2018 16:29:43 GMT
My jumper had that little bit of movement in it as well tom so it was wrong for me to say it was a fixed jumper.
So it too would have more than likely worked as a check valve if I had only open it a couple of turns (can't really see any point in this though).
I personally think that when water supply from the mains was first introduced into peoples homes a stop tap was specially designed to be this way to help protect the mains supply from contamination.
100 years on and it's become known has a traditional stop tap but the original purpose of the check valve design of the stoptap has been lost to the trade over the passage of time.
All I've done (due to this thread) is remember a lost lunchtime conversation from many years ago (although someone must have told that plumber who told me).
|
|
)
.
