Central Heating not Switching off

Hi I was wondering if anyone can help me with a problem that i have with my ch. my heating and water are on continuoius and will not switch of. I have tried switch it of at the a) control panel but it still remains on b) the room therostat, sill on the only way i can get it to go off is if i switch the boiler isolation switch off
Hope someone out there can help me.
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Sounds like you may have a frost stat which runs the CH when the outside temperature falls to a certain level - even if it is otherwise switched off. Try to find it, and check that it's not set at too high a temperature.
Roger
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Make and model of the timer/programmer please ?
Same information on the boiler would help lots.
Age and layout of the system is even more of a help.
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Thanks folks
Make & Model of Boiler: potterton Flamingo RS40s/50s make & Model timer : landis & Gyr RWB2 AGE about : 20 years
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After ruling out the frost 'stat outside, it could be that the switch terminals on the timer have eventually welded themselves together. If the timer is the same age as the rest of the system, I'd start looking there.
You will need a meter that can produce its own readings in the Ohms range to check it properly. Remove the timer from its back plate and check across the HW and CH connections to see if they are opening and closing as they should.
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On 31 Oct 2003 11:28:45 -0800, snipped-for-privacy@lineone.net (Billy N) wrote:

Have you got a frost thermostat on the system? If so, check whether that is overriding the control panel. It might just need resetting to a lower temperature.
PoP
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On Fri, 31 Oct 2003 11:28:45 +0000, Billy N wrote:

The main FAQ has a fair bit on controls heating controls.
--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
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