OFCH not heating water - only luke warm

BOBS

Hi and thanks in advance
As I say OFCH on and water only becoming luke warm -
what should i be checking for ?

took a look in attic and only thing of note is that the small water tank is full of very dirty water but nothing looks out of place.

Seronera

I presume by OFCH you mean Open Flue Central Heating, but we really need a better description of the system in your house and what it is doing before being able to make a helpful contribition

What type/make/model of boiler. Is it fully pumped? i.e.
do you have two 2 port zone valves or a three port? What type/make of cylinder do you have? Is the pump running, are the thermostats on your boiler/cylinder switching the pump on /off when you operate them. If the pump works have you tested for a blocked cold feed, Are the ball valves in your attic tanks operating OK when you waggle them (they can stick, particularly in the Feed/expansion tank for the central heating as it gets little use). Does the boiler carry on running or does it cut out fairly quickly when you put in on HW setting?

When did it last work properly? Has it suddenly stopped or has it been a gradual deterioration over time.

Come back to us with the bigger picture. It really helps people to give you better advice

The_Loan_Stranger

Or do you mean "Oil Fired Central Heating"?
We have had problems with the above before due the boiler needing a service, which included cleaning the heat exchanger and fitting a new burner nozzle/jet which solved the problem.

BOBS

Yes its oil fired central heating, think it may have been gradual and we only realised fully yesterday. Think I will book a service - has been two years since anyone looked at it.
Thanks for replies.