sime rads on, but not wanted

[uksparks]

sime super 80, the time clock is off and the boiler switch is set on summer, but the heating comes on during the day, but intermittently.
Any suggestions welcome

 

[kevplumb]

hot water switch might be sticking / sluggish

tbf not really up on the model

 

[Agile]

If this is a standard diverter valve model as I think it is then water leaked on the diverter switches or onto the PCB might be responsible for an immagined demand for DHW.

Tony Glazier

 

[Slugbabydotcom]

heating comes on during the day, but intermittently.

Would this by any chance coincide with running your hot water?

 

[kevplumb]

wish i'd thought of that

 

[uksparks]

the boiler is in a flat which i rent, so i can't tell exactly when its on or off. But the heating will come on while the tenant is out, and i think it stays on until she returns and runs the hot tap. I think it might be the diverter valve, perhaps the diaphragm is letting by, causing the valve to push up and make the micro switch, which runs the boiler.

 

[kevplumb]

if the diaphram is letting by (not my way of putting it ) it wouldnt work

 

[Agile]

Whatever the cause, I think the tenants who are presumably paying good rent deserve a proper boiler engineer to diagnose the fault and fix it promptly.

I do hope this Landlord does not attempt DIY gas safety Certificates!

Tony Glazier

 

[uksparks]

thanks for all suggestions, but im going to get new boiler installed, that should sort the problem out.

 

[Terry B]

The fault is probably due to a faulty divereter valve.
The rads are probably warmingup when hot water is being used.
There is no way to service this valve best to replace it sime part number 6243802.
The only other posibility is a faulty frost stat, but the Super 80 was not fitted with a frost stat, but one could have been fitted.