|
QUESTION:my wife has advised me that we are getting a new bathroom suite! she
would like one that has the taps in the wall rather than on the bath itself.
The shop told her that we cannot do this at present as we only have a
Gloworm Ultimate 50 boiler and an immersion heater, and not a combi.
Couple of questions that I would like some help with please.
1. Does a combi need any more ventilation space around it or external
venting than the present boiler (which is situated in the kitchen behind a
false cupboard door)?
2. Can I run the central heating via a combi?
3. Cost wise, will a combi work out more cost effective than the current
boiler/immersion setup?
4. How much should I be paying for a decent combi, and any recommendations
on make and model etc?
My wife likes lots of baths, so the immersion is on quite a lot, and
obviously the central heating is now on a fair bit. To give an idea on
costs, our electric bill per month is 52 and the gas is 36. I am in the
process of swapping from British Gas for both to Powergen, saving 200 per
annum, but that's another story
ANSWER: It depends on the boiler and manufacturer. Most manufacturers have
this info. on their web site if you look in the installer section.
Don't forget about possible flue space.
Before you do anything else, check the water flow rate at the kitchen
cold tap using a stop watch and a bucket. If the rate is less than
about 15-20 litres/minute, using any kind of mains fed hot water may
be disappointing.
Smaller combi boilers are quite limited on hot water production rate.
It can be as little as 9 litres/min, with better ones achieving
15-18lpm. bear in mind that this is for a 35 degree rise in
temperature, so in the winter will represent the total rate at bath
water temperature.
Normally a tank/cylinder based system will fill a bath very quickly,
so as another test, using a bath tap adjusted to the rate of the
intended boiler, time how long it takes to fill the bath.
Smaller combis can take 15 minutes easily, so certainly ask your wife
whether that is acceptable.
Another option would be to keep the existing boiler and heat the
cylinder from it. This would be cheaper to run than the immersion and
much faster to re-heat. You may need to replace the cylinder, but it
would be cheaper than a new boiler.
|
|
|
|
