What Type of Hot Water System?

What Type of Hot Water System?

Author
Discussion

jshell

Original Poster:

11,006 posts

204 months

Sunday 26th October 2014
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Are people going back to traditional boiler/hot water storage or mega-flow unvented cylinders rather than a combi-boiler only? I like the combi, but my heating engineer has recommended the megaflo system. I may be putting in an underfloor heating system in the new 50m2 extension...

Pferdestarke

7,179 posts

186 months

Sunday 26th October 2014
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I think it depends on many localised variables, such as water pressure (Combi is poor when delivering a shower and others are washing dishes or placing any other demands on the mains water supply)

How many people are in the house? How many bathrooms? How long is the pipe run from Combi to kitchen sink?

I have a 4 bed fairly large property with a WB 40 CDI combi and wait around a minute in a morning for hot water at the sink.

If my wife is in the shower and I fill the kettle it reduces her shower to a dribble. We should have stored hot water for that reason alone.

We also have fairly low water pressure in this area.

Renovation

1,763 posts

120 months

Sunday 26th October 2014
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Everyone keeps telling me to ditch the combi but I love that I only pay to heat, what I use and that it never runs out.

The ONLY issue is that it can't run two good showers at once - so when someone jumps in the shower they shout and the others have to wait 5 mins - it's never been an issue with four of us sharing the house.

Bill

52,472 posts

254 months

Sunday 26th October 2014
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Combis are a good solution in a small flat, but pants otherwise. A well insulated modern tank wastes very little heat in the grand scheme of things.

jshell

Original Poster:

11,006 posts

204 months

Sunday 26th October 2014
quotequote all
Thanks for the quick replies! There are 3 of us in what will become a 4-bedroom, 2 bathroom house, but will have elderly guests. Folks are getting old, so I can see them spending more and more time with us in future.

I love the combi, but if the gas goes or the combi fails we're fecked - no hot water. With the storage, at least there is the option of an immersion heater to get through! It's an ex[ensive install, though, and we lose cupboard space to get it.

GlenMH

5,203 posts

242 months

Sunday 26th October 2014
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As others have said: it depends on your water pressure AND flow rate.

We are lucky in that our mains is high pressure and, now that we have put a large plastic pipe in to the house as part of the lead replacement project, then we have great flow, too. I think it is a 32mm pipe.

We have got a WB CD37 or 42 and is quite capable of running 2 showers simultaneously due to the good water supply to the house. Thermostatic shower control valves mean that you don't get scorched if someone operates the one tap that can consume a good proportion of the supply pressure and flow: the kitchen sink cold.

I am not going to lie: I would love a megaflo system but I can't justify the disruption to install it or figure out where I would put it. The combi out of the way in the vestibule near the front door is the right solution for us.