Super_Paulie

The guy behind the counter had a 1" female iron and it went onto the end of my 25mm tap no bother. Said I need a 1" male iron but they didn't have any, typical. So I'll mooch around the internet tonight to see what I can find.

For the win... Hopefully. Plumbase says it's a 1" male iron. However they didn't have any...

This picture will help no one im sure, almost impossible to get a picture of it. I would say the one I'm having problems with is 11 tpi and the ones that all work are 10tpi, but it's tricky to measure.... Might just take the fittings to a plumbers merchant if I can find one local.

Right I have no means to measure the thread sadly. Looking at this with less pissed off eyes, I'm pretty sure the thread pattern is different. The 25mm tap that actually fits in it, the thread is different to the 1" bush that doesn't. Tap on the bottom, 1" bush on the top. Every bush or fitting I've tried has that same larger thread... So that's what's going on here, I need the bush/fitting with the same thread as the tap.

it might be tricky but i will try that when i get home after work. Proper sick of it, just need to get a move on!

tech specs claim 1" top and bottom on the 50l.

difference in sizes on the supposed 1" fittings.

Tapered fitting, no dice, exactly the same as my bush. Tap, just binds up, just making it worse. Honestly don't really know what to do now, the whole thing has been a massive sink of time, money and effort... Only thing that gets anywhere near is the 25mm fitting in the stop cock. I'm debating grinding the top few threads on the tank away with a Dremel? Dont have much to lose at this stage...!

I've ordered a tapered fitting to try it out. I've got the tap but I think it's just making things worse. Glad I started this... Literally should have screwed in and job done!

yeah all other ports are BSP, go in like a dream. Not a bad shout though, but looks like its not something i can pick up on my way home from work sadly. I'll see what i can come up with. Cheers fella.

yeah i did, but it was listed as new, still had all the bungs in place. Not totally unbelievable that the seller realised the same thing as i found, but all the bungs were unmarked. I borderline had to destroy them to get them out so i dont think they had ever been removed.

the technical document say the top and bottom are both 1" but i beg to differ. Even the stopper that came out was marked 1". I'll see how far i dare with the tap, it might just be the top thread that has a manufacturing flaw, fingers crossed.

I've bought a 1" tap to see if it needs recutting. Fingers crossed as I'm proper sick of this job now!

Only thing that remotely fits is this. It's wobbly on the way in but it holds water with PTFE on the threads.

Ok well this is driving me daft, see above. The 1" bush or any 1" fitting I have simply won't go in the supposed 1" bottom socket. The only thing I can get in is an old mdpe 25mm stop tap. I ordered what I thought would do the job, a 25mm to 15mm coupler. No dice, the threads are totally wrong and its no where near the right size. Honestly I'm going round in circles here, really open to any great ideas people might have? @Nickfromwales any ideas?

done! One annoying thing i found with that tank, all the fittings went in absolutely fine except the bottom one. The bush i got, 1" to 1/2 simply wouldnt go in. The one on the top fine, the 4 on the sides, 1 1/4 - 1/2, totally fine. The threads are all intact but for the love of god no bush or fitting would go in, just bound up immediately. The tech specs say its a 1" but something isnt right. What i did find was that a compression-fitting stopcock tap i had that was a 25mm MDPE to 22mm fit in, removed the nut/olive etc and the threaded section of the 25mm end screwed in and was water tight. No idea what went on there, but it was a rough few hours. So i guess i need to find a fitting to suit.

🤞

Hell of an idea that @Nickfromwales Any suggestions on which diverter? Most I can see are mid way valves, please don't say it's another Honeywell as my wallet is getting very light! Over the weekend I got everything piped up and the tank mounted on the wall/chimney breast, just needs It's connections to the return. It's 100mm off the loft floor so jammed some celotex underneath it to ease my worries of it falling off, which it won't as it's well on there.

cant thank you guys enough for all the info, its keeping me on the straight and narrow (hopefully). If you have a moment can you cast your eye on this drawing @Nickfromwales to let me know im on the right lines with all of this? mainly because i dont know anyone how has used a buffer tank or who has UFH so getting answers from pals is non-existent. also: a) using the buffer as 2-port, am i right in thinking that you need the return connection top and bottom rather than say both coming in at the bottom or does it not matter? b) how do i fill the thing, just via the filling loop on the boiler? Multiple pints are owed due to all the info from you lads.

yeah ive been looking at your drawing and ordering up the gear i need for the weekend. 1.1/4 bushes down to 1" then compression elbows. I assume i need a bottle vent or similar for the top of this thing and a drain at the bottom?

this thing is heavier than id imagined!

sorry for the spam guys, guilty as charged. In fact... i can tee this into the UFH return before that returns back to the primary return surely? The bypass rad wont return circulate into the rad circuit because the UFH doesnt come back in until after the height of the last rad?

this drawing might be more accurate. I guess the solution is a separate tee just for the bypass rad as i assume the bypass return needs to be the highest back to the boiler.

would i be right in thinking that a bypass radiator return tee'd in below the height of the last rad would make the radiator circuit warm by reverse circulation? i guess the only way out would be a separate return like the UFH return, higher than the last rad?

I know what you mean but space is an absolute premium sadly. I could do it, but it would be a multitude of bends to get things back where I need them. Hopefully maintenance will be few and far between and draining down the top leg of this shouldn't be too much hassle... We'll see!