Why doesn't everyone hate combis?

Alex1983

Should be about getting the right designed system for your property. A combi has no place in a big multi bathroom property just like a big hot water cyclinder and heat only boiler has no place in a flat.

A correctly designed system with correct hot water draw offs eradicates most of the problems you describe.

scottishblondie

I love my hot water tank. We never run out of hot water and it's available instantly. Sadly for me, I've just bought a house with a combi boiler and the delay in getting hot water is already annoying. Not a deal breaker, but definitely annoying. When it breaks down in however many years from now, I'll be replacing it with a non-combi and a hot water tank!

Waterlily24

I love the combi boiler and we have quite a big house with three bathrooms and have no problems. Saying that the baths and shower aren't used at the same time. Only two of us live here but quite often at weekends there are 5 of us.

Up until this house we have had 'ordinary' boilers but we wouldn't go back to them. Love not having to worry about if the water is heated up.

patman99

I used to work on a new-build estate and every house has a large tank installed as well as a combi boiler.


I spoke to the plumber who told me that the ch feed runs through a coil in the main tank. This heats up the water. This, in turn, acts as a heat reservior pre-heating the ch water before it goes back through the boiler, thus reducing heating costs.

Ectophile

coffeehound wrote: »

Long delay (typically a minute or so) before hot water comes out of a tap.

Either there's something wrong with the boiler, or you have a ridiculously long run from the boiler to the tap. Having a long run from the hot tank to the tap also requires you to run through quite a lot of water.

Flow-dependant temperature, sometimes meaning that for properly hot water, only a slow flow can be used.

You need to get the boiler fixed, or get a more powerful one. When I lived in a flat, even a weedy 23kW boiler was fine for the hot tap, but not so good for running the bath in the middle of winter.

Bizarre and infuriating tendency to slow down the hot water flow until eventually it is a trickle, at which point the boiler switches itself off and (having wandered off to do something else) you come back to a cold trickle coming out of the tap!

Get the boiler fixed. There's something wrong there. Every combi boiler I had could fill a bath without any strange behaviour.

Pause the hot flow even for a moment, like if you accidently knock the shower lever, and the damn boiler immediately shuts down. You then have to wait (again) while the water goes alternately hot and cold until the wretched thing has got its life together.

It shouldn't take long to heat up again.

And of course during the household's morning ablutions, the boiler can only do one thing at once, so the central heating goes off and the house goes cold...

If your house goes cold that quick, you need more insulation. Or set the heating to come on a bit earlier.



I have lived with both combi boilers and system boilers. Combi boilers have two big advantages - you don't need a hot water tank, which frees up useful space, and you never run out of hot water.


I currently live with a traditional system boiler. When I do the washing up in a few minutes, I'm expecting to get a bowlful of vaguely warm water. That's because I had a bath earlier. If I had a shower instead (it's an electric shower), then I would have heated an entire tank of water, just to fill one washing up bowl.

comeandgo

I have a combi and don't have any of your problems. Had family staying this weekend so two showers working at same time, no problem, never has been.

Mr.Generous

Biggest issue with Combi's is that there is more to go wrong, and they do fail more often. Expansion vessel and diverter valve being 2 common problems. When the hot water is on it does switch from the heating, but as many have said is this really an issue? My stored hot water takes longer to reach the taps than most combis, up to 5ltrs at kitchen sink before its really hot.

stator

I've got a hot water tank system for the first time, always had a combi before.
I much prefer the tank system.
I recognise exactly what you're talking about trying to get hot water out, I used to have that problem in my old house. Trying to turn the hot water tap on enough to get hot water, but not too much that the water is luke warm instead of hot. I was left for 2 months without hot water when it broke down (crappy landlord). If it was a tanked system I could have used an immersion heater.
I also love having an airing cupboard. Makes your clothes nice and warm

missile

patman99 wrote: »

I used to work on a new-build estate and every house has a large tank installed as well as a combi boiler.


I spoke to the plumber who told me that the ch feed runs through a coil in the main tank. This heats up the water. This, in turn, acts as a heat reservior pre-heating the ch water before it goes back through the boiler, thus reducing heating costs.

Que? That sounds like BS. :rotfl:

It cost what it costs to heat water to whatever temperature. Even a well insulated tank looses heat.

Sea_Shell

We recently had our mains water cut off by a burst pipe (luckily just for a day).

Glad we haven't got a mains fed combi boiler in this scenario, as it would be no showers for us that morning.

We still had a loft tank full of cold water, and a tank full of hot water. OK, we could only flush the loos once (mains fill) without using a bucket, but it would have been a nightmare morning with a Combi !!