two hot water cylinders linked together?

[ben28]

I have recently had a look at a plumbing problem in someones house, They have issues with radiators not heating up enough and a problematic shower hot water issue.
I'm not sure if the two problems are linked.
They are currently running a Myson 70/90 oil fired boiler its a largish house with 4 beds 3 bathrooms.
The previous plumber has installed a second cylinder next to the original by linking all the pipe work together they are both situated in the loft (with no pipe insulation).
Apart from anything else is this set up against the regs? and could this extra cylinder be causing problems with the rads not heating up and the shower hot water issues?
Any thoughts anyone..?

 

[muggles]

Apart from the obvious lagging issue, I don't see any problem with linking cylinders, provided it has been done correctly.

"a problematic shower hot water issue" tells us b*gger all about what the problem actually is, please expand

The extra cylinder won't be stopping the rads heating up.

 

[Razor900]

Whats the head of the cws above the cylinders in the loft?

If you turn half the rads off do the others get hot?

How many rads, what controls to system, Trvs, hot water bypass, pump, type of system, type of showers etc????