Conventional boiler.... comeback Combi all is forgiven!

I agree almost 100%.

I would say though that I fit a fair few and even in big places where the combi side feeds a kitchen, utility or small shower room.

They do have a place. But not where a different system is better.

50kw in a 4 bed :LOL: funniest thing I've read this week ;)
 
Sponsored Links
The problem with combis of any size is that they are "energy intense" The main heat exchanger has to get to 70c+ to generate hot water even for a small demand , and then when the tap is turned off the heat exchangers just sits there dissipating unwanted heat.

Do that 30 or 40 times a day and it has a big impact on energy performance..

compare that with a cylinder where the boiler fires 3-4 times a day for hot water....

it so obvious really..
 
Sponsored Links
Might be a bit overkill for modding an ikea draw set, my bosch multi tool was perfect. All my broadband stuff now neatly concealed.


Numb nuts hasn't managed to Google any more twaddle? :LOL: :LOL:
 
I think its a bit strange that the automatic answer for a lot of people is to shoot down a combi as crap.

I usually give my customers this example (me), which is someone living on their own, in a well insulated 2 bedroom flat, no occupancy during working hours (which are not always fixed), 20 degree target for about 4 hours a day, and a shower running from the 30kW combi, who doesnt have to worry about when the hot water is on to have the shower (my favourite thing about a combi) who has a gas bill of £20 a month.

the fact the boiler may be cycling etc and not rated low enough for heating doesn't bother me, even if it would save me 50p a month on gas.

the bottom line is that combis are great in certain situations, and wholly inappropriate in others. having the ability to recognise those situations is what its all about as far as making customers happy goes.

in my opinion etc etc
 
The trouble is the combi is only really suitable for singles or couples, may be young families too but only with one bathroom...any more and they are not fit for purpose..

a storage combi is a different beast though...
 
the bottom line is that combis are great in certain situations, and wholly inappropriate in others. having the ability to recognise those situations is what its all about as far as making customers happy goes.
I agree, they have their place - but too many plumbers seem to have some sort of implant that makes them immune from consideration of other options. We've seen in this thread, yet again, how some people are proud to state that they won't consider all options when designing a system :rolleyes:


I see two old wives tales come up yet again about thermal storage.

The stat on the thermal store in my flat is set at 60˚C - not 70˚, not 80˚, but 60˚. It gives quite adequate hot water which is limited only by the supply. Don't think I've measured flow rate, we do have a static pressure of around 6bar - but it's a 1/2" service and all 15mm copper internally. Still, does an impressive blast when directing the hot tap for the washing machine into a bucket (only a matter of seconds to fill a 2g bucket).

When I fitted the thermal store, I took the trouble of actually measuring standing losses. Not guessing, not listening to old wives tales, but measured it. I shut down the boiler and left the store on the immersion heater, after a couple of days (to allow everything to stabilise) I read the lecky meter, and a few days later I read the meter again. The difference worked out to 80W average - somewhat less than the naysayers keep claiming.
I did the same with the combi in the house - but working from the gas meter. Just keeping itself warm to as to provide hot water "quickly" rather than in up to a minute*, it used the equivalent of about 160W. Yet it has an eco mode, but what's the point of a hot water system that only delivers hot water when you've finished using it !
* Yes I timed it, from cold it can take a whole minute to deliver hot water to the tap at the end of about 6foot of pipe.

True, the store and it's insulated box does take about 1m2 of floor space in the garage (which is under the flat), but the benefits far outweigh that. The tenant seems very happy with it - and the old boiler hasn't broken down once since I stopped using the combi function on it.
 
but a combi will fire 20-30 times a day for hot water
More misinformation. Some have small water vessels and preheat heat exchangers to prevent this. Quality models do not cycle. My ATAG has a pre-heat heat exchanger and does not cycle when a tap is on for a second or so.

I find it amazing how misinformed so-called professionals are. Many can't handle figures for sure. :(

So tell us which boiler do you have?..... You don't have an ATAG
 
Guys, have you ever heard the phrase "Never wrestle with a pig because you both get dirty and the pig likes it"?
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top