You are reading a single comment by @Howard and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Howard
Dramatic_Hammer
The Viessmann one (111) is 46L and as far as I can tell is blended with the combi output to give higher flow equivalent of a 150L unvented tank, whatever that means.
The Vaillant one (938) is more opaque as to how big it is and what it actually does - flow seems the same as the equivalent model without a tank but I think the idea is that a) you’ve got instant hot water with no startup time and b) if someone runs a tap during a shower, there’s additional capacity and flow is maintained at higher temps.