Inconveniencing a tenant

[Refurb to Rent]

I suspect the reason for the complexity is in one of the OP's posts above. The system has been put in to "pre heat" water going into the combi (as some of the low output systems were). This means there will be valves and switching in the combi flow line that might fail and leave the boiler gagging for water. Ditto the tenant.

If it was mine, I would both drain it and restore the combi cold flow back straight to the mains as one job. Physical removal could then happen at a later date.

Sell it to the tenant as you, the lovely landlord, spending £££ to proactively increase the reliability of her hot water.....there will be a knock on benefit that any boiler guy arriving in future will not spend half a day scratching his head before servicing/fixing/providing a certificate for the boiler as it will look like all the others.

[Bramleyapple]

Not sure whether being a LL is for me yet, and may need to sell this little property in the near future-although I had wanted to keep it incase I needed it in the future for myself, but it has to earn its keep ,so decided to have the system left in a state that could be 'reversed' as others may have enough knowledge /trustable contacts etc to put the system back to work . Apparently leaving the tubes full and disconnected will cause fast deterioration , so theyre to be drained, but other than that Im not aware that the firm is going to do much more than you suggested , Refurb . Sadly Im anything but technically minded and when I query stuff , they blind me with science !