Heating coming on when switched to Hot Water Only

[elizamrris]

Hi,
I have a Halstead Ace High Combi boiler.
Since last night, the central heating is coming on even when the switch is set to Hot Water Only. The only way I can turn the heating off is by switching the bolier off completely. Can anyone help me with what the problem is on this?

P.S I don't know if this has anything to do with it but our water pipes in the house are frozen today. The pipes have frozen many times before but haven't affected the boiler.

ANY HELP apprecaited?

 

[twgas]

Your pipes froze because you turned the boiler off, presumably to save a few pennies , don't know if there's frost protection on your boiler, which may cause your problem.

 

[bengasman]

Probably frost protection being activated, has been known to happen when it is this cold.

 

[nightfisher]

This problem is the diverter valve stuck in the heating position so over rides the hot water demand .