Pre-heat for Unvented cylinder

[ecowarm]

Just browsing the web this evening and came across this site, and they are advertising a solar unvented cylinder to pre-heat an existing unvented cylinder. Look here Solar Hot Water System UP - Unvented Pre Feed

I can not see how this is anyway legal, opinions please............

Eco

 

[justlead1]

Hi Certainly the drawing and labeling are incomplete with regard to temp / pressure controls etc. Which could lead to persons mimicking these designs in the real world. altering the balanced cold would be the least of your worries.

 

[oldplumber]

if your buying a 2nd solar cylinder why not replace the original one anyway and have a more effective and less ***bersome sytem, seems like another bright idea jumping on the bandwagon for flogging to the general public, then running away.