connecting Aga to mainsflow type cylinder

[Leadman]

Hi,
Not sure I have the right section for this but ..
I need to replace a standard indirect cylinder and header tanks with a Heatrae Indirect Megaflo unvented cylinder or similar.

At present the system works fine and there is no overheating of the cylinder, but in order to get rid of the header tanks and increase flow to the hot taps (which is the object of the exercise) I need a mainsflow type cylinder.
The problem is the only viable heat source, which is anoil fired four oven AGA.
I am told that the direct mainsflow systems are inefficient when used with an Aga and therefore would like to fit the indirect type.
Has anyone out there done this before and if so, did you just connect the flow /return from the Aga as with the standard cylinder or was some sort of in-line diverter valve needed to avert the possibility of the cylinder water boiling.

Thanks

 

[WHPES]

What you are suggesting is potentially dangerous and illegal. You cannot hook up an old fashioned AGA to a Megaflow as the AGA is an uncontrolled heat source (it could be a time bomb). - you would have to use a thermal store system instead (which are every bit as good as a Megaflow and you still get rid of your header tanks)

If your AGA has one of those pressure jet conversions done to it with boiler thermostat etc then you can have a Megaflow but you need to speak to an expert.

 

[dancinplumba]

Indirect mains connected cylinder same thread ?

 

[Pipes Plumbing]

Agree with WHPES on this one... If it's an older AGA without full thermo' control and high limit stats, then it would be potentially dangerous to go unvented on this and you should be looking at a vented thermal store with appropriate gravity circuit and heat leak provisions, as if it was a standard solid fuel setup.

If it has been fully converted, then it's not that far removed from a standard oil boiler setup in theory.

 

[Leadman]

Thanks for the replies.

Yes same thread and yes, modern Aga.

Baxi suggested a Dunsley Neutraliser but I suspect the chap was making a couple of wrong assumptions about Aga ovens as a neutraliser wont stop overheating, which would be the potential problem. (although it would allow re-routing with a stat fitted)