Pulsacoil 2000 - not enough hot water

[Mannisenmaki]

Hi everyone,

I have a Pulsacoil 2000 thermal store which is connected to an off-peak timer with a boost button. The off-peak timer currently runs from around 2:30am to 8:30am and the boost is currently set to be on from 6pm to 7pm. Please note that I have no control over when the off-peak timer runs - this is controlled by the electricity tariff that I am on.

The problem is that there is never enough hot water. In the morning, the water runs out before the second shower (even while the off-peak timer is still running). In the evening, there is not even enough for one bath.

As I understand it a thermal store will gradually lose heat over time and the water will become cold. However, I would not expect the water to go cold so ssoon after the timer has been running. Also, the water goes from piping hot to stone cold in the space of a few seconds which doesn't sound like a gradual loss of heat to me!

I found another website which suggested a possible solution (making sure that the expansion tank is full) but unfortunately it didn't solve the problem.

Any help that you can provide will be gratefully received as it is really frustrating not having enough water.

Maany thanks,
Nick

 

[ChrisR]

Also, the water goes from piping hot to stone cold in the space of a few seconds

eh?
Not with you.

 

[Mannisenmaki]

Also, the water goes from piping hot to stone cold in the space of a few seconds

eh?
Not with you.

I mean that one second the water is hot and the next it is cold.

 

[Rachel2007]

Hi Nicki

I appreciate you posted some time ago but I was just wondering whether you had sorted out your problem? I live in East London in a flat with a pulsacoil 2000. The hot water runs out after the first shower in the morning (there are 4 of us living there so this is a real issue). The bath will not run hot even first thing and 'boosting' provides little more hot water or causes the system to trip. SO frustrating! Our landlord is not getting it sorted and I kinda need to know if it's a real problem before I call a plumber in myself. We've also tried adding water to the tank. There is a pressure issue too (too high and gradually dwindles to a tickle during the course of the day) and I know what you mean about the hot cold hot cold thing!

 

[hi-spec plumbing heating]

have you any red leds flashing on the pcb ?

 

[Rachel2007]

Hi

Thanks for responding!

Yes a red light flashes. Sometimes it flashes fast and sometimes slow, but it always flashes.

 

[hi-spec plumbing heating]

if it's a slow flash one per second this indicates the flow thermistor is faulty
fast flash which is about seven per second is the pumped thermistor is faulty.

this problem will give an unstable hot water temp