Combi Boiler questions

thecrater

Hi all,
I'm thinking of replacing my current conventional boiler set up with a combi boiler to get something more efficient, eco-friendly and reclaim space in the airing cupboard in my 1-bed flat.

I have the following questions:

• Combi-boilers provide hot water on-demand. What's the point of the timer?
  I thought that since the water is heated on-demand, the thermostat and TRVs would control the temperature and "demand" hot water for the radiators based on the thermostat temperature? how would the timer fit into all this?
  
  
• Would any of this impact the availability of hot water from the taps in the kitchen and bathroom?
  
  
• Do combi boilers use a lot of electricity? and if yes, why?
  
  
• Will the boiler stay "on" all the time but only spring into action on-demand? If yes, then how efficient is this feature? would it be better to have a power on/off button?
  
  My current conventional boiler maintains the temperature of water in the cylinder until I switch it off (this is where a timer is handy)

trinidadone

timer - very good if you want the central heating on and off at certain times.

your right, you get hot water on demand.

combi boilers use little if any electricity, maybe the odd light glowing.

yes the combi will stay on until demand, although you can switch the off completely if you want, thus resulting in cold water being delivered when the hot tap is switched on

plumb1_2

The point of the timer is that it controls the time you want your heating on. Just using the trv's will bring the heating on when the temp of the rooms fall., so if the boiler heating switch is on, it will work 24/7.
Plus you will also need a room stat, as per building regs.

Combi's dont use much electric
if the heating is off or on you will still get hot water on demand, having to turn a on/off switch al the time will brake the switch through excessive use. And is not to currant standards


Get local installers to give you a quote, and they will explain it to you.

thecrater

thanks very much for your prompt reply.

Owain_Moneysaver

Better to get one without a timer, and have a separate programmable thermostat, that lets you have different room temperatures at different times of day/night.

martin.cat

A couple of pointers

Don't go for the lowest rated as this limits amount of hot water flow

Avoid having drain for condensate outside as it will freeze up during cold spells

Make sure system is flushed properly so water is clear as this will lead to problems

A programable thermostat is good as it allows you to set temps for different times. I have mine set for 18 at night so it's never too cold and 23 during the day when were not at work

The combi will save you money. We used to pay £85 per month 7 years ago for gas and that went down to £35 and only £50 now. Believe me we use it. That's for a 2 bed house which is fully insulated. The wife and daughter have bats most nights too

southcoastrgi

martin.cat wrote: »

The wife and daughter have bats most nights too

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