Digital shower- pumped- issue

[lucyjk87]

Hi all,
Looking for thoughts on the following problem.

Bought a house which has a relatively new looking aqualisa digital shower (single outlet).

Its wonderful, for 6 mins 43 seconds...then pressure drops, its struggling to maintain temp (digital screen states "warming") and digital box (TN16-1DE) makes pretty loud noises.

Im not a plumber or anything but what ive worked out is that this is a pumped digital shower connected to a copper cylinder (both of which are on the same floor as the shower and physically all close together). The cylinder is gravity fed from a big tub in the eaves on the second floor.

What i think is happening is that either the cylinder is running out of water or the tub is which means the pumped digital shower cant get enough water to push through to the shower head.

So what id appreciate is peoples knowledge on whether the restricting factor is the capacity of the cylinder, the tub or neither and is something like the flow/pipe size etc.

My aim here is to learn and understand the system and whats wrong, i wont be trying to resolve this myself, ill be getting a plumber or heating engineer.

All thoughts welcome.
Thanks
Lu

 

[JohnD]

Probably the loft tank. What are its dimensions? How deep is the water inside?

Also

Run the shower into a bucket. Time it to full. How many litres per minute does it deliver.

 

[lucyjk87]

Thanks for this.

So i cant easily get to tank but its about 70 length x45 width x50 height

And about just under 2/3rd full.

Ill put the pics i could get of it, excuse the poor quality- im balanced over a soil pipe.

Havent done the litres per minute test yet.

 

[JohnD]

No lid on it so it will collect drowned spiders and other wildlife.

 

[lucyjk87]

Delicious

 

[Rodders53]

Looks more like a CH system feed and expansion tank to me. Not very well installed or insulated (or covered). Around 18 litres max

Any cold water storage tank would (should) be very much larger than that.

Pics of the HW storage cylinder and the pipeworks around may help?

 

[lucyjk87]

Ill get a pic as soon as possible. There is a small boiler in the kitchen but that certainly doesnt serve all the hot water needs so i suspect its some kind of split style system- heating via the little boiler, hot water via the cylinder.

Thanks for all the input, its all very helpful

 

[JohnD]

Can you show us a pic of the cylinder and its pipes please. Full length, including the top part.

 

[Stuart981]

Are the little supply valves on the hot and cold connections to the controller fully open?