Really appreciate help with these central heating quotes

[TanDiy]

Looking to replace warm air heating in our 70's 4 bed detached house. Water feeds to one bathroom, cloakroom, kitchen and utility room. Johnson & Starley say they can supply parts for our boiler for another 10 years but we are renovating the house and think we should bring the heating 'up to date'.

We have been quoted two systems and really would appreciate some advice..

OPTION 1: Vailant Ecotech 837 Combi with 12 radiators digi room stat

OPTION 2: Valiaint Ecotech 624 with 12 radiators and Megaflow 145L unvented indirect cylinder.

Our thoughts- the combi sounds excellent as no water cylinder but concerned about multiple hot water outlets and read lots of bad things about reliability. People seem to be recommending the Megaflow system but this looks very complicated to us - our warm air system has never gone wrong in 15 years - we want something as simple as possible that will be reliable and no hassle.

Really would appreciate any advice on this - should we maybe look for the more basic vented arrangement. Thanks very much.

 

[45yearsagasman]

I'll start of by asking a couple of questions.
1, Whats your water pressure like?
2, How many people live in the house.
These are important (among others) in determining a suitable system.
Both boilers are good IMO. The flow rate from the combi is fairly good but will suffer if two taps are opened at the same time, therefore the unvented will cope better providing you have the cold supply to go with it.
Thats a start, but I'm sure the expert installers on here will give you the benefit of their vast experience.

 

[TanDiy]

Hi,
(1) I do not have the figures for the pressure but the heating engineer did measure this and said that pressure and flow are fine for a combi.

(2) There are four people in the house - two teenage girls hammering the shower every day - this is another area that i am considering - we currently have instant electric shower and I wonder whether we should move this on to the heating as well.

Thank you

 

[slapper]

Hi,
(1) I do not have the figures for the pressure but the heating engineer did measure this and said that pressure and flow are fine for a combi.

(2) There are four people in the house - two teenage girls hammering the shower every day - this is another area that i am considering - we currently have instant electric shower and I wonder whether we should move this on to the heating as well.

Thank you

If your going for a combi, youll will be wise to keep electric showers in the event that the boiler breaks down you can still shower

 

[dcawkwell]

For reliability go with the system boiler and megaflow.
The boiler will be more reliable and you have the immersion
in the megaflow tank as backup for hot water.

A combi will be less reliable.

But don't expect to get the next 15 years with any new boiler
problem free.

 

[xr4x4]

Don't go for a a megaflow unless you want to recharge the air gap every 6 months.

Aren't main made by the megaflow company.