Talk:Increase Hot Water Capacity

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I'm a bit confused about some aspects of this article.

  • It starts off talking about hot water "running out" which implies some sort of stored water system.
  • The first heading is a "bigger tank". UK (and uk-d-i-y) usage seems to be 'tank' for cold water storage, usually in the attic, and 'cylinder' for hot water storage (vented or unvented). A bigger tank won't affect the supply of hot water: a cylinder will.
  • Higher Thermostat Temperature
    • With a stat temperature of 95°C the boiler's flow temperature would have to exceed that. What are the implications of this?
    • What are the implications for other higher-than-normal thermostat settings in terms of, say, efficiency of the system?
  • Drain Heat Exchanger. Do we need four links to the eponymous article in one short paragraph?
  • Move Thermostat Lower Are there any energy efficiency or other implications to moving the cylinder 'stat lower and lower?
  • Solar Preheater. Is this really an easier option than putting in a bigger hot water cylinder?
  • Use CH Circuit Heat
    • With a heat bank or Thermal Store - with say a 100kw heat exchanger in the heat bank what size exchanger should one use for the CH side, and how much effect in terms of heat extracted from the CH system (which may be sized at say 10 - 15kW for an ordinary sized house) can one expect? And since in a typical system once the store temperature starts to drop the boiler output will be diverted to re-heating the store, how much will this arrangement mitigate the hot water running out issue?
    • With a combi - but with a combi surely the hot water only runs out when the boiler breaks down? And since the boiler's output is diverted to DHW production how does one obtain heat from the CH system?
    • With a conventional HW tank - as for thermal store, isn't the boiler's modest output going to be diverted to reheating the cylinder long before it runs cold?

Maybe I just don't understand these schemes. Can you give some diagrams?

  • Electric Boost. You say this scheme "has not been tried by the author", implying the others have. Can you elaborate?
    • In the case of having a 3kW electric pre-feed to a 24kW minimum combi how much effect will that give?

-- John Stumbles 00:17, 7 February 2008 (GMT)


Shower boost pumps increase hot water use. Slowing them down thus reduces use and prolongs available shower time.

Perhaps you could explain how you slow down a shower pump?

--John Stumbles 12:17, 10 February 2008 (GMT)