Does valve or thermostat fire boiler please?

[Dannyk]

Need to get someone in to change motor on valve as no hot water unless valve is manually locked open but it may be a while as plumbers busy.

Will locking the valve open cause the boiler to fire or is it the thermostat that fires the boiler? Currently using immersion but would prefer gas as cheaper.

It's a newish Vaillant Ecotech under warranty which is why going to get pro in. I could understand old Baxi but these fangled condensing things give me a headache and am getting on a bit now!

Many thanks.

 

[ShaunCorbs]

The valve does and with you locking it open / manually doing it the thermostat won't do anything so I wouldn't recommend it

 

[Dannyk]

Many thanks, I feared as much. Will continue using immersion.

 

[jtsplumbing]

Depends how much hot water you are using just lock it open until your hot water tank is up to temp then close it off

 

[heatservice]

If you lock it open, water will only flow to cylinder when there is a demand for heating, and then your cylinder stat will not control your water temp, so be careful as water could reach 80 C or more.

 

[waddycall]

Is the cylinder vented or unvented?

 

[Dannyk]

Is the cylinder vented or unvented?

It's unvented.

 

[waddycall]

Probably best left alone then.

 

[Best]

Good point from Waddycall!
The motorised valve for unvented cylinders is a component of the unit and one of the main failsafe parts and should never be left manually on, because overheating is the only way those cylinders can become a bomb

 

[Dannyk]

Many thanks folks. Left on immersion.
Someone hopefully coming Monday afternoon.