Limited Hot Water from Pulsacoil 2000

Been called to a flat with a Pulsacoil 2000.

The tenant (it's a rented property) is complaining that the hot water provided is only good for one shower in the morning. When her partner returns home in the evening there is barely enough for a wash let alone a shower.

Both immersions have recently been replaced due to leaks from the stat tube and both function fine. They are supplied via a E7 timer as there is no dedicated off peak supply to the property. This means the store is heated between the hours of 2am & 7am (pre-set times of timer) with the option of a 2 hour boost during the day. This is really only relevant when the tenants are home, ie weekends or days off.

My question is this. Is this normal operation for this type of system? How long is the store of water expected to stay hot after 5 hours of being heated? I was thinking of swapping the timer which is mechanical for a digital equivalent, this would give the tenant more control over switching times for both night rate and day rate (boost) electric. What do you think?

PS I've checked the top up tank, that's fine.

Many thanks.

the store maybe heating up correctly, but other factors can cause ltd hot water.
take the front cover off and to the right hand side is a small pcb with a flashing red led light.
tell me what its doing ?
regards
mark.

Hi, thanks for replying. The red LED is flashing twice every second which I believe indicates all is well, or at least that the PCB thinks all is ok.

Cheers

Steve