How to install, service and repair Unvented hot water cylinders, plumbers/gas engineers 

Excellent video Derek on the unvented cylinders, i will need to watch it few times for a better understanding also make my own diagram on the different parts and correct way of fitting it. 👍👍😀

Ill give this a good watch. Im considering fitting on of these or an unvented thermal store cyclinder to a self build for a wet UFH radiator mix system. Be great to see a video on thermal stores.

Thomas Bradwell Thanks Derek

Great information, many thanks

Thank You for this video!

This is the first video I've watched that mentions the Tesla 15mm to 32mm dry trap tundish. Even Gledhill's instruction manuals for their Stainless Lite unvented cylinders doesn't mention it, and they come with a regular 15mm to 22mm tundish. In my new installation I will have a redundant 32mm waste pipe in solvent weld. This pipe has a horizontal run of 500mm between joists, followed by a 90 elbow and then a 200mm run horizontal before another 90 elbow and then falling vertically 2.5m and joining the soil stack behind the downstairs toilet. Will this be sufficient bore and length to accommodate a Tesla tundish? I've also emailed Gledhill technical with the following: 'm about to have installed a 200L Direct unvented Gledhill cylinder. I've studied the manual and wanted to know why you recommend that the direct cold water points (single taps, toilets etc) are fed from the direct main rather than from the balanced cold connection after the Reliance inlet control group? I am installing the cylinder in the bathroom (1st floor) and I have the opportunity to run a 22mm pipe direct from the 25mm MDPE pipe mains inlet, straight to the cylinder. I could then run from the 22mm balanced cold feed out of the inlet control group to the bath, teeing off in 15mm to the bidet, sink and thermostatic mixer shower valve, a cold feed to an electric shower (used as a back-up) and then onto the downstairs cold points. Wouldn't that keep the whole system pressurised at 3 bar and be preferable to teeing off at ground floor level? I was also thinking off installing three 22mm pressure guages (which all seem to come with PRV). One would be installed on the pipework next to the cylinder, before the inlet control group. One would be installed on the hot water output at the top of the tank and the last one would be installed on the cold balanced feed output of the inlet control group. This way, all parts of the system could be monitored and checked when a draw-off point was operated. Would this be a worthwhile thing to do in your opinion? Thanks for any advice you may be able to offer.

Great video, always good knowledge, very informative 👍

Hi Derek, I noticed you had a set up from a boiler where the condensate was installed with push fit pipe, I thought this wasn't allowed due to condensate water rotting the rubber seals?

Nice video 👍🏻 What’s the purpose of the secondary circulation mentioned in this video. Didn’t really understand that bit.. 😬 Thanks Asian Jon. Training.

Just watched 😁 top vid Derek 👌

It would be great if you could make a small video on how to service the unvented cylinder, what to check for, including some systems which have hot water expansion vessels external built. Thanks 👍👍👍

Great explanation Derek :) Any chance you can post a video on Primatic cylinders? Not very common these days but still knocking about ;) Thanks, Hussain

Very nice

Thanks for the video I’ve got my g3 with you next week any other videos you recommend I watch derek?

Anywhere we can get those diagrams, thanks Derek,

Why do they make and sell 15mm inlet control groups?

Thanks 👍👍👍

Can the d1 pipe be fitted into a soil stack if the tundish has a one way valve?

👌

Nice video :-) Connor

worked in australia and every year there are people killed with these. When they explode they flatten everything, super heated steam. Often some one has connected the ptr in the wrong place, the ptrs are not always fail safe they can corrode and then will not activate the lever to vent the water. I have had this happen to me and I still keep the defective ptr lever. Just warning you guys!

In your earlier part of the production, you showed our #hotun dry trap tundish on the Ariston unvented cylinder. www.hotun.co.uk We have a traditional open sided construction to enable ANY amount of flow (dripping or full flow) to be easily seen by the end-user, however we have now introduced another innovation. We have designed a clip-on water detection and temperature sensing, battery-powered audible, and visual alarm system. We will call you to chat about this. Many thanks

Chris Taylor

No need for the music