Hot Water Cylinder connections - Help Please

DomMCT

Hi,

I just purchased a Joules standard Indirect Hot Water Cylinder. On the top there are three holes, one for the immersion, one for Hot water outlet and a third hole.

What is this hole for and what do I need to plug it as there was no such hole on the original tank.

I purchased a 3/4" stopend, but this seems slightly too big to screw into it?

Thanks in advance.

Dominic

The Continental Op

Not a plumber but I think the extra third hole is for taking off water for a shower. My understanding is you can get air trapped at the very top of the cylinder and the extra hole a little way down from the top avoids air going into the pipe.

Try the 3/4" stop end again and check the treads on both the cylinder and the stop end?

You could have either a tapered stop end or one with parallel threads. The one with a tapered end shouldn't go all the way in and needs ptfe tape on the threads to make a seal. The stop end with parallel threads can be sealed on the threads with ptfe tape but also with a washer.

Doolittle51

It probably needs a fitting with a 3/4" M.I. Thread. You can get a 3/4" M.I. to Compression straight coupler and put a blanking plug on the end of it. Is the thread on the connection on the top of the tank not the same?

Calahonda52

without seeing the cylinder, any advice re plugging is dangerous

pls post details of the tank, it should have a manual with it or was it bought at a boot sale

The Continental Op

Calahonda52 wrote: »

without seeing the cylinder, any advice re plugging is dangerous

pls post details of the tank, it should have a manual with it or was it bought at a boot sale

Never seen a manual with a copper cylinder and I've bought and fitted 5 in recent years. If the immersion is in the top then good chance its a copper cylinder. But joule make both Stainless Steel and copper cylinders.

I've just double checked and the last copper cylinder I installed at home here is exactly the same as the OP's in that it has an extra 3/4 take off fitting half way down the top. Didn't think it was a joule cylinder but think it was an Irish made one. I just plugged the hole with a 3/4 inch plug.

listermint

It it not standard for immersion near top. Hot water out the top and expansion and side is coil in and out and finally cold feed in the bottom side . So 5 holes all things considered.

Personally I had to put an extra hole in mine to feed a pumped shower system. So perhaps that's your 3/4 Inch ?

Calahonda52

manuals
https://joule.ie/joule_products/cylinder/

The Continental Op

Calahonda52 wrote: »

manuals
https://joule.ie/joule_products/cylinder/

Now try finding one for a copper joule cylinder with a top entry immersion and that extra 3/4 inch connector the OP is on about. I've tried and failed maybe I'm not very good at looking?

Vita nova

Any cylinder I've bought recently has had that extra hole/outlet. I asked them in Heat Merchants what it was for and they said it's for a shower connection and there was a plumber there to confirm that that was the case.

I just use the normal hot water / vent outlet at the very top of the HWC for all hot water including showers and blank the shower outlet. I asked them for a suitable blank in Heat Merchants and I used it with a rubber o-ring and no PTFE and have had no problems.

listermint

Vita nova wrote: »

Any cylinder I've bought recently has had that extra hole/outlet. I asked them in Heat Merchants what it was for and they said it's for a shower connection and there was a plumber there to confirm that that was the case.

I just use the normal hot water / vent outlet at the very top of the HWC for all hot water including showers and blank the shower outlet. I asked them for a suitable blank in Heat Merchants and I used it with a rubber o-ring and no PTFE and have had no problems.

If it's pumped shower don't do this. Anyone using the hot water during will impact it. It should have it's own 3/4 supply. Tapping off the normal top feed isnt recommended

Vita nova

listermint wrote: »

If it's pumped shower don't do this. Anyone using the hot water during will impact it. It should have it's own 3/4 supply. Tapping off the normal top feed isnt recommended

That's good advice, in my case I don't have any pumped showers.

CoBo55

Vita nova wrote: »

Any cylinder I've bought recently has had that extra hole/outlet. I asked them in Heat Merchants what it was for and they said it's for a shower connection and there was a plumber there to confirm that that was the case.

I just use the normal hot water / vent outlet at the very top of the HWC for all hot water including showers and blank the shower outlet. I asked them for a suitable blank in Heat Merchants and I used it with a rubber o-ring and no PTFE and have had no problems.

Sorted;)

bubbagumss

have you a photo and name of water heater is it.electric or solar

bubbagumss

have you a photo and name of water heater is it.electric or solar

DomMCT

Thank you to one and all!! Extremely helpful & much appreciated. It is a copper cylinder purchased from Screwfix (no Manual). It does seem that it is an option for a Pumped shower. I found that a 3/4 Flange Plug fits snugly. Obviously its a different size or thread to the 3/4 pipe stopend.

You guys are a great support!

Cheers!

Dtp1979

DomMCT wrote: »

Thank you to one and all!! Extremely helpful & much appreciated. It is a copper cylinder purchased from Screwfix (no Manual). It does seem that it is an option for a Pumped shower. I found that a 3/4 Flange Plug fits snugly. Obviously its a different size or thread to the 3/4 pipe stopend.

You guys are a great support!

Cheers!

3/4” brass I hope....