Invented cylinder - no heating when water is on?

[MummyBear]

Hi All
We recently had an unvented cylinder fitted. Everything seemed to be working fine but we have recently noticed that If the water is on then the heating won't come on until the water is finished. Is this normal?
Thanks in advance for any info!

 

[picasso]

It could have been set up as hot water priority but you need to ask the installer.

 

[dilalio]

And also if it really is an “Invented” cylinder...

 

[MummyBear]

I blame autocorrect!

 

[dilalio]

I blame autocorrect!

... your honour!