Vaillant VRC470f current cylinder temperature is readinzero

[Mboursnell]

I have a Vaillant VRC470f and an ecoTec plus 428.

When I look at my "Cyl. Temp. Current" it says zero degrees. Does that mean the cylinder thermostat is not wired up correctly somehow, or is there some setting I need to change?

 

[ALEC1]

the installer could well have used a regular cylinder thermostat as opposed to a cylinder sensor that detects and displays the actual cylinder temperature, so you can set the temoerature to the nth degree..the latter offers certain benefits.

Both are acceptable to Vaillant.

 

[Mboursnell]

Thanks. So if the installer used the existing cylinder thermostat it will still feed the temperature back to the boiler, so the boiler can shut off when the desired hot water temperature is reached?

The only disadvantage is that you don't see the temperature on your VRC470f (not a big problem) and that you can't set the temperature digitally but only analogue-ly (!)

Is that right?

 

[ALEC1]

correct, but with a cylinder thermostat you never see a number on the vr 470..

 

[Mboursnell]

I can set the temperature by using either the original thermostat on the tank, or by using the VRC470f. I have tested to see which of these work by setting one to high and the other to low. It seems that both affect the temperature. If you set either to 40C whilst the other is set at 60C, you get a low temperature.

Is this right? It seems a bit odd.

 

[ALEC1]

yes very odd..

if you have the cylinder sensor then the cable is grey and you can see the actual hot water temperature in the cylinder on the controller.

if you have a cylinder thermostat you cannot see the actual temperature of the hot water on the vrc470 on the controller in installer level>system configurations..

 

[Mboursnell]

yes very odd..

if you have the cylinder sensor then the cable is grey and you can see the actual hot water temperature in the cylinder on the controller.

if you have a cylinder thermostat you cannot see the actual temperature of the hot water on the vrc470 on the controller in installer level>system configurations..

I can't see the temperature in the VRC470f so assume I have only a cylinder thermostat.