Which boiler...completely clueless!

[CJMommy]

In process of purchasing medium sized four bed house (4 double rooms, 2 reception rooms and kitchen diner)

After renovation it will have 1 bathroom, 1 ensuite, 3 toilets (2 showers and one bath)

There are two adults and two children.

The house is 1979 built and the boiler has not been changed since then. House currently has hot water tank which will be removed in the process of creating the en suite as thought that combi would be the best option but reading everything on here, i'm not so sure??

We don't complete the sale for a few weeks but presume this needs to be sorted pretty quick as moving walls, new kitchen/bathroom/ensuite and total redecorate in the 8 weeks we have prior to moving....Help!!

[specialsubject]

combis mean no hot water tank, water is heated on demand. So when it is cold, rate of hot water flow will be slower. I believe not compatible with power shower, needs electric shower which heats its own water.

BUT you only heat water when you need it, and you don't need space for hot water tank.

[flow4]

I have had a combi boiler for 15+ years, and never had this mythical problem with water pressure. It supplies water to a bathroom on the floor above it and a kitchen on the floor below it, and the power shower works fine, even if the dishwasher or washing machine are on.

There are different 'powers' of combi boiler these days, with more powerful ones designed for larger houses. My house isn't particularly large, but it's tall, with radiators on 4 floors; so I deliberately had a more powerful boiler installed, although the plumber told me I should be ok with the smaller one, to be sure it could cope!

Hot water systems with separate tanks are inconvenient and inefficient, imo. You heat water you don't need, then have to keep it warm - or waste it. And there's nothing more annoying than running out of hot water half way through washing up - or worse, when you're in the bath!

[wonkylegs]

We have a combi on a 5bed/2bath house. 2 adults & 1 child and a parade of visitors all liking nice powerful showers.
It's fine.
Make sure you go for a decent make (Worcester Bosch, Vallient & Viesmann all get good which? scores & have a good rep in the industry) and make sure it is sized for your needs. An underpowered boiler will have problems with flow, pressure etc.
A plumber will be able to give more detailed advice but both WB & valiant have size calculators on their websites dependent on house size & family need.

[CJMommy]

Thank you
I didn't know about the calculators so will take a look. I've been on ?Which and those three do come up as best buys.

How are the megaflow different to the others and why would you have one of these?