I personally like Alpha for simplicity with service and repair boulter for ease of installation i would stay clear of Baxi they are sh*t dont much like Vaillant but aftersales excellent check around and speak to a few local installers see which way they point you, as for measuring flow rate you get a thing called a weir gauge ( basically a cup with a hole in it with graduations and figures on it)which tells the lites per minute or gallons per minute of flow. or just fill the bucket and time how much minutes it takes to fill a set litreage and work it out from there

hope that is of some help

regards

steve

Ah...mea culpa.  I should have said OIL FIRED as no gas  

I fitted a Vaillent EcoTech Plus in mine in the end - I couldn't decide between betwen a conventional system and a combi......but went for a combi for ease.....

It is a fantastic boiler - I went for a larger size than required, which means you can use two taps with ease, and the temp is too hot on max.

It also has a fantastic feature - Aqua-comfort I think it is called.  It allows you to connect a conventional 2 ch time clock, or one the Vaillent 'bus connect' timers.  The Hot Water channel puts the boiler into 'aqua mode' - which gets the boiler 'ticking over' ready to provide hot water quickly on demand.

It also has an inbuilt filling loop which many boilers do not, and an inbuilt pressure release valve.

I have a 'bus' connected timeclock, and this gives you a screen display which shows the status of the boiler, gas valve, pump, heating, water etc.  Shows temp, allows you to boost the temp, advance, bed early etc.

Excellent IMO!

the clue is in the post :-D :-D
I have a 'bus' connected timeclock, and this gives you a screen display which shows the status of the boiler, gas valve, pump, heating, water etc.  Shows temp, allows you to boost the temp, advance, bed early etc.

regards

steve