Water System removal?

[ssb1973]

Hi all,

I live in a modern house, and I am not sure whether the water system the builders installed is efficient cost wise.

Basically, we have a cold water tank in the attic where the cold water is fed to. Then on the first floor airing cupboard we have an immersion copper boiler to heat hot water, there's also two actuators (one for the central heating and one for the hot water) in the airing cupboard.

Then in the utility room downstairs there's a Vaillant combi boiler that has a timer attached to control the central heating and hot water times.

We also have two mixer showers in the bathrooms upstairs.

My question was can I run the whole hot water / central heating from just the combi boiler?

I was thinking of removing the copper boiler from the airing cupboard to make some stairs to the attic, and remove the cold water tank from attic to make a further bedroom in the attic.

Would this make my water system more efficient if I remove those "unnecessary" items. Or are the copper boiler and cold water tank required?

 

[dextrous]

How do you know that it's a combi boiler and not a system one?

 

[TicklyT]

'Efficiency' depends on your point of view - Do you mean energy efficiency, more efficient use of the space occupied by the system or efficient operation from the users perspective?

Removing the stored hot water sytem leaves you reliant on the instantaneous heating capacity of the boiler for all your hot water needs.

Most combi boilers can only supply one outlet at a time.

If, as I suspect, you actually have a condensing system boiler, instead of a combi, you will have no water heating capability at all.

The cold storage tank and hot water cylinder make up any short term deficiencies in your mains water supply when your demands are at their maximum.

Removing the hot cylinder also removes your back-up immersion heater if (when) your boiler fails.

The best choice for you depends on many factors, including:-
Your hot water usage pattern.
The capabilities of your existing boiler.
The cost of a replacement boiler that would meet your requirements.
The water pressure and flow rate available from your water supply.

 

[Onetap]

You could supply all the hot water outlets from a combi boiler (if yours is a combi)and all the cold outlets from the mains. I wouldn't; most people who know anything about combi boilers would advise against it in a house. This would do away with the cold water storage and the hot water storage cylinder.

You could install an unvented hot water storage cylinder, and get rid of the cold water storage tank. You'd have no stored water if the mains pressure failed.

 

[ssb1973]

@ dextrous

I'm not sure whether it's a combi or system. But when the hot water or central heating timer kicks in the vaillant boiler gas comes on and starts heating the water within there. Also the immersion copper boiler actuator light comes on when hot water timer kicks in. Is there an easy way to find out whether its Combi or system?

@ TicklyT

My point of view for efficiency is for saving money, we also have a water meter so the costs are even more, but that's a different story.

I don't think the boiler is condensing, as it is definitely an older type, as the the house was built in 2001.

Currently, there is only my wife, myself and small child living in the house, so our hot water usage is not really high, just bath times, or shower time, washing dishes.

@ Onetap

Is there any good purpose for the hot water storage cylinder, as a combi boiler could supply the hot water on demand, I understand the pressure dropping if someone turns the hot water tap on while somebody is having a shower, but most of the time, no one uses the taps while someone is having a shower.

I think this all comes down to storage if the combi boiler failed or the mains pressure failed. It's a gamble whether on the likelihood of those two things happening.