Economy 7 Should my "On Peak" switch be On

[LizMac42]

I have a Gledhill PulsaCoil Echo system in my new retirement flat which is running on Economy 7. However there is a separate switch in a cupboard which is labelled "On Peak" - should it be on or off please. I have switched all the underfloor heating off on the room switches and have plenty of hot water but the person who set up my Economy 7 timer left this On Peak switch on. I have turned it off - is this OK please.
My 80 year old brain is failing to understand this system.

 

[James]

I would leave the on peak switch OFF for the time being, if you find you are running out of hot water or it is getting cold during the day, then turn it back on.
you wont break anything by turning it off and it will save you money.

 

[LizMac42]

Thank you for answer James - I hope you get this as the boxes are all greyed out

 

[James]

got it loud and clear,
have a great evening and feel free to come back if you have any more issues.