RM cylinder coil 1 and soil 1 hot water storage

[Selvaraj]

I’ve got advantage invented hot water storage RM cylinder.
I have got coil1 soil 1
Both are connected with copper pipe.
Looks like one for heating and one for hot water but the soil 1 for hot water pipe has a stopcock
What is the difference between coil1 and soil 1

 

[Scott_D]

Are you sure it’s soil?

 

[ShaunCorbs]

Don’t you mean solar ?

 

[Selvaraj]

Don’t you mean solar ?

Yes I believe it is solar.
The pipe connected to hot water cylinder with stopcock.
Should that be closed.
While other pipe connected to coil 1 has Honeywell value
Problem was that today no hot water
So I set thermosatat manually and then boiler started
Not sure why suddenly no hot water though neat thermostat showed hot water on

 

[SimonG]

Let's have a picture or two.