New DIY "Plumber" needs advise for loft water tank supply nut and olive?!?

[Ghostrider17]

Hey guys

I've "repaired" my mums loft water tank from leaking but I'm unsure if I've done it correctly so thought I'd join this great forum and ask some advice from some people much smarter than me.

Basically my Mum was worried that her overflow from the loft kept running water so I went round and had a look thinking it was the Float Valve,turns out I was right as it was trickling and overflowing,it was also the old part 1 type from what I understand. I fitted a new one in my own tank a few months ago so knew what to do.

The tank was filthy inside and also full of rotten wood which was odd. After checking all the nuts I told my mum that it would be fine until the next day when I could pop and get her a new one. When I got back home she phoned me in tears saying the roof was leaking,so I went round and turned her water supply off and drained the tank as I couldn't find the isolation valve.

I then noticed there was a leak in the supply nut on the outside of the tank (on the right of the photo) going into the float valve. I can only guess I loosened it my mistake when I was checking things by hand.

The next day I got the new valve,float and a washer kit just in case. Gave the water tank a good clean,removed all the limescale and fitted the new float valve. Tightened everything up and turned the supply back on. There was still a major leak coming from the supply nut where the pipe goes into it,so the water was turned off again quickly.

I completely removed the back nut to look inside and I couldn't see any kind of washer or olive? I found this odd as I always thought a nut connection needed one? Also my parents have lived there for nearly 40 years and they've never had a tank leak before.

I'm really not sure if I did the right thing here but I found a right sized olive in the washer set and placed it over the pipe under the bolt and reconnected and tightened everything up. Water came back on and everything looked ok. I had a coffee and then went back up to check 20 mins later. There was a slight bit of moisture around the nut where the pipe was connected,probably about a quarter of a drip so I tightened it up more and everything's seemed to be ok since.

I'm going to pop by tomorrow and check things over. I'm just worried I did the wrong thing and things will start leaking again. Obviously being in the loft its hidden from view unless you go up and folks are getting on a bit now.

Could anyone give some advise and tell me if I've done anything wrong so I can put things right?

Thanks loads in advance and sorry for the long winded post,I just wanted to give as much detail as possible.

Just so you guys can see here's a pic of the water tank before I butchered it.

 

[Best]

This is the one I got with the float valve so I'm assuming it will be a fibre washer?

View attachment 30757

That looks to have an internal taper which will suit a brass or copper olive. However, I notice there is a fair bit of flat face also, which will probably hit against a flat type washer. Some are more sharper than that tail.
I would say that particular tail in photo is really for a nut and olive connection to do it properly

 

[ShaunCorbs]

i would say either would work and bet you paid a pritty penny for the valve

 

[Ghostrider17]

i would say either would work and bet you paid a pritty penny for the valve

Nah,it was only about £7 from screwfix,unless you're taking the mickey lol.

 

[ShaunCorbs]

Nah,it was only about £7 from screwfix,unless you're taking the mickey lol.

thats a good price esp for one with brass nuts normally all plastic these days

 

[Ghostrider17]

That looks to have an internal taper which will suit a brass or copper olive. However, I notice there is a fair bit of flat face also, which will probably hit against a flat type washer. Some are more sharper than that tail.
I would say that particular tail in photo is really for a nut and olive connection to do it properly

Thanks for that,really appreciate it. I've got more olives but I think I'll try the washer for now as from what you said it's a safer bet for someone less experienced like me.

I have 1/2" fibre washers YIF and also 1/2" fibre washers which are labelled for flexi taps but are a fair bit thicker than the one on the left. Is it best to use the thicker ones or does it need to be the YIF ones?

A massive thanks to everyone who's advised me on this. I know it must be annoying to get a complete newbie asking for advise but I really do appreciate it. I just want to do the best job I can so I dont have to worry about my parents having any problems down the line.

 

[ShaunCorbs]

left one

 

[Ghostrider17]

thats a good price esp for one with brass nuts normally all plastic these days

I find Screwfix to be great mate,especially for bits to help out home DIYers.

 

[ShaunCorbs]

I find Screwfix to be great mate,especially for bits to help out home DIYers.

ive just had a thought that looks big you sure its a 1/2 thread ? (should be 20mm dia ish)

 

[Ghostrider17]

left one

Thanks again,the left YIF one was the one I was going to use until I saw the thicker ones in the set. I'll let you know how I get on tomorrow. If the olive hasnt damaged the pipe I replace the tail and put the proper washer in but if it has Ill do what you suggested and fit the service valve.

 

[Ghostrider17]

ive just had a thought that looks big you sure its a 1/2 thread ? (should be 20mm dia ish)

Well its the tail that came with the float valve mate. Just checked the washer against it and its an exact fit across the top flat part,does that sound right?

 

[ShaunCorbs]

Well its the tail that came with the float valve mate. Just checked the washer against it and its an exact fit across the top flat part,does that sound right?

yep just looks mega big in your pic 😀

 

[Ghostrider17]

yep just looks mega big in your pic 😀

Haha,that would be my rubbish photography skills. Ill let you know tomorrow how I get on.

I'm grabbing the service valve on the way,for the sake of a couple of quid Ill have it with me if the olive has damaged the pipe,just hope that if I need to use it theres enough pipe before the bend to fit it but Ill check before I go cutting. I did fit a new washing machine supply tap a few months ago at my own house which is why I think I got confused with the whole olive/washer thing.

Thanks again,really appreciate it.

 

[Best]

Sorry to say this, as it will sound very negative, but I wouldn't use a tap connector type fitting, to connect to a ballvalve that is designed for a nut and olive. They are one of the most pointless fittings to use on side entry ballvalves. Why a washer seal is deemed satisfactory or necessary there is beyond me.

 

[ShaunCorbs]

Sorry to say this, as it will sound very negative, but I wouldn't use a tap connector type fitting, to connect to a ballvalve that is designed for a nut and olive. They are one of the most pointless fittings to use on side entry ballvalves. Why a washer seal is deemed satisfactory or necessary there is beyond me.

Exactly the same with toilet ball/float valves do you use a nut and olive on them doubtful

 

[Best]

Exactly the same with toilet ball/float valves do you use a nut and olive on them doubtful

It is not exactly the same with toilets.
Toilets ball/float valves usually were plastic tailed, so not as ideal for nut and olive connection.
But most toilets are bottom entry ballvalves that more suit a flat seal because of 4 reasons, -
(1) supply pipe has often not enough up and down movement (even though it really ideally should have) for typical 1/2" needed for compression joint.
(2) pipe requires usually installed neatly, so can be better looking with a sharp bend away, rather than just straight up or offset from floor
(3) Many plastic or brass tailed cistern valves are made to suit flat washers.
(4) Plastic tailed valves more easy damaged using a nut and olive joint.

Whereas a side entry ballvalve on a toilet often will have plenty of movement on the pipe and especially on a cold water tank in a loft normally the mains pipe will have lots of movement on the pipe to aid installing or removing the complete valve with tail.
Never seen a properly done compression joint leaking on a tank ballvalve, but have seen lots of fibre washer solder fittings leaking, some very badly and causing water damage. Just another weak link in plumbing with a limited and unknown lifespan.

 

[ShaunCorbs]

Not the fluidmasters they can do both

And don't agree with your last part there both the same if done badly but haven't come across one installed correctly leaking

I've even seen tap connectors installed old school style with string never leaked

 

[Best]

Not the fluidmasters they can do both

And don't agree with your last part there both the same if done badly but haven't come across one installed correctly leaking

I've even seen tap connectors installed old school style with string never leaked

Some fibre washers just perish eventually, and really bad leaks occur. I have come across lots because I tend to do a fair bit of maintainence work. Maybe some of the fibre washers weren't good quality. Scary when you see the remains of the fibre washer is just mush. I like the rubber type washers made by Hepworth.
I think if the ballvalve was made for an olive, then the sharp edge against the washer is also a problem.
Yea, I know the Fluidmaster tails are designed to do washer or olive. Good design.

 

[ShaunCorbs]

Same do a shed load of maintenance in schools etc

Normally find the nuts arnt tight enough which cause the fibre washer to swell a lot more than designed

 

[Best]

Same do a shed load of maintenance in schools etc

Normally find the nuts arnt tight enough which cause the fibre washer to swell a lot more than designed

I suppose that could be due to plumbers afraid to over tighten and damage the fibre washers.
I am always wary of disturbing fibre washer joints and prefer the strength a compression olive joint gives.

 

[ShaunCorbs]

You would be surprised a fibre washer joint can take more of a shock load than a compression joint (both done correctly)