Reccomend me a combi boiler..

[HERTS P&D]

Is the Biasi a combi or is there a hot water cylinder and a non combi boiler ?

Did you read the title of this thread or the first line???

Andy

 

[Mottie]

Combi

 

[bernardgreen]

Did you read the title of this thread or the first line???

Yes I did, and I just re-read it, Motman was asking for recommendations for a combi, he did not ( at that point in the thread ) give any indication of the type of boiler being replaced.

The reason for asking was to maybe avoid the life style change that comes when hot water comes no longer from a hot water cylinder nut instead from a combi..

 

[Mottie]

I did indicate in my third post that my mother was getting good hot water from her combi but yes, up until then I hadn’t actually stated that she already had a combi.

 

[bernardgreen]

I did indicate in my third post

Which I did miss....

 

[vulcancontinental]

If you go the Intergas route choose a guy who understands how to set them up regarding heating and hot water temperatures. Anyone can fix a boiler to a wall but they need to understand certain system requirements (that comment should really be applicable to all installations but sometimes is not). Find an installer who loves them and has fitted many as they will know what to do. One of the moving parts omitted from the boiler is considered important by nearly every other boiler manufacturer and this needs to be accommodated.

In the interests of clarity I work for a competitor boiler manufacturer, do not install anymore, am happy to recommend an installer I know to put Intergas into my old customers houses as he knows what to do but would not fit one myself.

 

[John D v2.0]

Which parts to they miss out? Diverter would be nice but it's more likely to fail from crud in the system. Ev would also be nice.

Fan
Diverter
Gas valve
Pump
Dhw flow turbine
Expansion vessel diaphragm
Edit forgot: pressure guage (and prv if you're unlucky)
Combustion Air flow switch (thanks Bernard)

 

[bernardgreen]

If memory serves me right there is no differential air pressure switch to check the fan is pushing air through the combustion chamber. The controller probably relies on (1) tacho feed back to say the motor is rotating and (2) that the fan fitted is to the motor shaft in a way that cannot fail. Or it is an inside out motor where the rotor is the fan.

 

[John D v2.0]

It's not so much that the fan is spinning, the boiler needs to know there is enough air flow in the flue IE not restricted.
If you cover the flue or fit one that's too long it should cut out

 

[Wildcat1961]

It's not so much that the fan is spinning, the boiler needs to know there is enough air flow in the flue IE not restricted.
If you cover the flue or fit one that's too long it should cut out

Zero governor gas valve (1:1).
Gas flow being proportional to fan speed.

 

[John D v2.0]

Zero governor gas valve (1:1).
Gas flow being proportional to fan speed.

Not sure whether you are disagreeing? Are you saying if the flue is blocked the boiler should still fire as long as the fan can rotate?

 

[Wildcat1961]

Not sure whether you are disagreeing? Are you saying if the flue is blocked the boiler should still fire as long as the fan can rotate?

Sorry, forum rules prohibit any form of gas advice.

 

[John D v2.0]

it's not gas advice to say which are the moving parts, it's in their marketing brochures

anyway, for completeness I realised you meant gas flow is proportional to the air flow through the combustion chamber and venturi hence it provides interlock against a completely blocked flue. The fan still spins with a blocked flue but there won't be air flow. Still doesn't seem safe that it would operate fine with a partially blocked flue though.
the other components missed out are
EV (but you have to supply an external one...)
AAV (most AAVs are screwed closed anyway!) and
diverter valve+diverter motor (but you often need NRVs to stop the warm water floating around your heating system)
auto bypass (but you have to supply an external one)

meaning the moving parts are
gas valve, fan, pump and DHW flow sensor

 

[gasbanni]

The price your mum was quoted seems fair enough.

 

[Wildcat1961]

it's not gas advice to say which are the moving parts, it's in their marketing brochures

anyway, for completeness I realised you meant gas flow is proportional to the air flow through the combustion chamber and venturi hence it provides interlock against a completely blocked flue. The fan still spins with a blocked flue but there won't be air flow. Still doesn't seem safe that it would operate fine with a partially blocked flue though.

Google is not always your friend, especially when searching for nearly 3.5 hours for not much gain.
What is your line of business John if you don’t mind me asking?