Do unvented cylinders require a 'gravity' drain?

[DevsAd]

Hi again.

Exploring options for my bro's flat. One is to convert to a pressurised system.

The preferred location for the new unvented cylinder would be where the current vented one is in his airing cupboard. Problem is, it would be tricky to get a gravity drain from this to the outside (he had to have his new boiler fitted in the roof hut for a similar reason to do with the condensate drain).

I know there's pumps and stuff, but that's pants.

Do unvented cylinders require a 'gravity' drain like this, or have I misunderstood (I'm guessing it's to do with the tundish thingy?)? If it is required, are there any solutions that don't require 'gravity'?!

Thanks again.

 

[ShaunCorbs]

Yes they do or a pumped drain

 

[Riley]

Are you G3 if not it might be best to let your installer assess it to ensure that flow/pressure and termination options are all up to scratch

 

[townfanjon]

^^^ as above, you need adequate pressure and flow before you can even go down the discharge pipe route . Not a DIY install , its more than “just a cylinder “

 

[DevsAd]

Many thanks all.

No, not a DIY install - I'm aware of special quals required for pressurised systems. Just trying to be as informed as possible with all the options before letting my bro loose on finding a plumber.

Thanks Shaun. Not really keen on a pumped drain system - as would also have been the case with the boiler in the same location - so the new cylinder will require a different home.

Cheers, much appreciated.