I finally need piglet john

[donajimena]

Hope you are around piglet. My central heating is doing its own thing! I switched it on last night and nothing happened. Tried it on timed. Also nothing. So I have put it off.
I've just got up to find it firing away merrily and lovely warm rads which whilst welcome I can't switch it off.
I'm renting and can't get hold of the landlord til Monday. Is it ok just to switch off ? Its a Vaillant Eco something model

Apologies if this doesn't help but I had exactly the same problem with my heating last week and it turned out the batteries in the thermostat on the wall had gone flat. For some reason it made the boiler go nuts and turn the heating on and off at random times throughout the day and night. As soon as I replaced the batteries normal service was restored.

good point, if it's got a wireless room stat.

Is there a hot water cylinder?

Firstly its a Worcester Bosch I got the make wrong (Vaillant was my last house) With the switch in the off position as shown it fires up and the heating is on
There is an ancient thermostat on the wall which I assumed was a remnant from the now removed back boiler as it doesn't seem to do anything.
I am controlling the furnace by turning boiler down to zero.
Also when I switched it on Fri night to take the chill off nothing happened. I'd like to know if its me before I call the landlord.
I cost him a fortune with emergency gas safe engineer when I thought I had carbon monoxide poisoning on the day I moved in. Turned out to be my stress levels and residual oven cleaning product burning off but he did fit a carbon monoxide detector PDQ

In off position

show us the wall stat.

is there a hot water cylinder?

No cylinder. .. just off to photo thermostat

Make is sunstat. Its currently set to 15

Couple of points

It's lunacy to have no working wall stat. Turning it up to 22 it should click and the boiler should start if timer is "on"

Did you discover the radiators got hot during or after you had been running the hot tap? That's common if the diverter valve has failed.

Ill give that a bash. Is a wireless thermostat expensive?

a wired stat is simpler and more reliable. These days most people would go for a programmable stat, which might, for example, turn on the heating at 7am to 8am on weekdays and 9am to 10pm at weekends, and have a higher evening temp than during the day, and prevent the nighttime temperature falling below 16 at night.

It would be a bit of a surprise if the old stat has actually been disconnected. Turn it up to 22 and set the boiler to "on," see if the rads come on. The wiring is very simple and can be re-used.

Does running a hot tap make the radiators warm?

I haven't tried the hot water/rads yet but will do in the morning.