How many hot water cylinders can you have with economy 7

[gardener1214388]

I have a hot water cylinder; vented into a large loft header cold water tank connected to an economy 7 timer that gives me two good hot mixer showers a day before it goes cold
Question:
Can two hot water cylinders be used with the same setup; economy 7 timer connected to two cylinders; for example if ideally placed side by side ?

 

[OwainDIYer]

yes, but you would probably need separate timers if they're the sort only rated for 3kW each.

 

[doitall]

Yes, but it depends on the load at the CU and what else you have connected.

What had you in mind with the extra cylinder.