Megaflo or what ?

[stevewestern]

I am buying a house with an almost new combi boiler feeding an indirect hot water tank, both downstairs.
I want something close to mains pressure hot water to supply a shower upstairs and a bath downstairs so am thinking of a megaflo type of tank.

Any thoughts or suggestions about this or alternative makes I should look at and what sort of size do I need to think about - there are 4 of us though one bathes at work and the other 2 shower most days - I am the only one who will be wallowing in a hot bath, glass of wine in hand...

 

[muggles]

The first thing you need to establish is whether you have sufficient flow and pressure from your mains to run an unvented cylinder.

If you do I'd choose an OSO Super Coil

 

[stevewestern]

OK, thanks for that - I hadn't even thought about flow and pressure..

As we are still a little way off getting possession of the house it may not be easy to find out - I assume it is easy enough to check but what is sufficient ?

 

[muggles]

As an absolute minimum you'd be looking at maintaining 1 bar pressure at 20 litres per minute flow rate, but it'll be better with more. Should be at least a 25mm diameter incoming main with 22mm copper feeding the cylinder

 

[ALEC1]

Thats 1 bar at the proposed outlet not at the entry into the property..

water companies have to supply 1 bar at the boundary and 10l/m...1 bar equates to about 10m, or two and a half floors enough to fill a tank in the roof at most uk properties...

 

[stevewestern]

Again, many thanks guys.
Clearly I have a lot to learn and all help is much appreciated !

I guess I'll need to look at the pipe that comes into the house as and when I can.

Now, just in case there isn't enough pressure or flow then what are my options ?

 

[muggles]

Keep what's there and install a pump

 

[stevewestern]

Keep what's there and install a pump

Really ?
Is it that simple ?
I know the tank is too small so would want to install a larger one but assumed that a megaflo would be the best bet.
However, a decent sized tank and a pump would be way cheaper and easier given that money is going to be very tight - I assume a hot and cold pump would be needed but that can go next to the tank and thus increase the water pressure to the whole house right ?
None of us take long showers so I don't imagine the header tank will need to be looked at but there is plenty of room for a bigger one if needed.

You may have made my day muggles !

 

[CBF]

first i think you need to see exactly what you do have re your 1st post "combi with an indirect cylinder" you will have one or the other it's very unlikely you have both

 

[stevewestern]

first i think you need to see exactly what you do have re your 1st post "combi with an indirect cylinder" you will have one or the other it's very unlikely you have both

Oh no, am I proving myself to be a total fool on these things then..?
I thought a combi could be used to keep an indirect tank full of hot water..
I'll try to find out what the boiler is and see if the sellers can give me some info about water flow etc.

I'll be back once I know more in an attempt to look less ignorant !

 

[muggles]

A combi can be used to heat a hot water cylinder, it's just a slightly unusual setup as it also heats water for the taps by itself. Normally done where the cylinder is the opposite end of the house to the boiler

 

[CBF]

it's ok it can be confusing if you aren't used to it, what you prob have is a condensing boiler not a combi

 

[stevewestern]

Again, many thanks for your patience and help !

So, if I have a condensing boiler (combi or not) then can this be used to heat a megaflo type of tank should I go for one.
If a normal tank plus a pump is sufficient then I could just replace the tank with a larger one, with a bigger header tank if it cannot cope with the demand and a pump to ensure we get a decent shower upstairs. As it is both boiler and tank are next to each other downstairs with the header being up on the first floor (it is a bungalow-style place with bedrooms pushed out into the roof so there would be almost zero head of pressure for a shower). The only hot water upstairs is a tiny basin. There is loads of space to store water in the roof space.

Am I getting there ?

 

[CBF]

yep it sounds like you are, fyi if you do decide to go unvented i wouldn't go for a megaflow they are way too expensive

 

[stevewestern]

yep it sounds like you are, fyi if you do decide to go unvented i wouldn't go for a megaflow they are way too expensive

Well, from what I have been told on here it seems that a megaflo isn't the only way to go so I expect a larger hot water tank and a pump will be what I go for with a second header tank just in case.
Is there any big advantage of a megaflo-type tank apart from maybe slightly more flow ?
We are used to a combi slowly filling our bath so anything better than that will be an improvement !