Two hot water cylinders connected in tandem?

Is it possible to add an additional hot water cylinder in the floor above the existing cylinder and connect them together? I am exploring doing this as I need to increase the amount of hot water and I do not have room to replace the existing cylinder with a larger one.

My existing system is a pumped open vented fed by a baxi back boiler.

Thanks in advance for any advice you are able to give.

Garry

i dont think having one above the other would work, (although, i cant quickly explain why just dont see the hot going between 2 and via vent pipes without causing a problem with supply or temp ) better to fit one on its own circuit and divide the load to the hot taps between both, careful planning would be required to ensure both could be replenished by existing loft tank and vent route did not compromise safety etc

There are several pproblems associated with having two cylinders.

The only way that it would definately work OK is with each seperately controlled as explained above.

They CAN be placed side by side and paralleled but then have to be very carefully balanced and ideally have a symetrical layout.

Tony