My Vaillant app - reported outside temp

Hardware Heatpump
1

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The ‘MyVaillant’ (Android) phone app is reporting an outside temp. of 7.5C when two other references say it’s about 2C, and sticking my head out the door confirms the latter. Some time back I put an offset in for the OAT of -1 which seemed to work. Now it’s colder and the reading’s way-out.

The important thing is the heat pump is performing as-per its weather compensation curve of 0.4 (currently), giving a flow temp of 32C at 3C outside, so I’m not too ‘bovvered’ but wonder if the app reports some kind of 24-hour average ? If the sensor is faulty then surely the unit wouldn’t be giving the right flow temp?

Any ideas?

Anyway, as this is its first cold spell it looks like ‘Baby’s First Defrost’ - aaaahhhhh. I’ll get me coat.

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Cheers, Andy

2

Where is your white Vaillant outdoor sensor placed?

Ideally you want it on a north facing wall out of direct sunlight.
As soon as any sun hits it, it will start giving higher readings.

3

Hi Mick,

It’s on a north facing wall out of direct sunlight! I can’t see any other reason for the discrepancy. I’ve also checked using a hand held thermometer.

4

Faulty sensor?
Is it actually reading it? Maybe stick your hand over it / warm it up, see if it changes in the app?

Outside temp shows on the sensocomfort too? Is that reading the same? You’d assume to info comes from the same place?

There does look to be a temp sensor on the back of the Arotherm. It’s not reverted to using that has it?

Just lots of guessing there! :man_shrugging:

5

Thanks, Mick.

Yes, I’ll have to look deeper. Right now it’s not important as I’m running on ‘pure’ weather comp and all seems well, so as you say it must be measuring outside temp accurately somewhere!

Cheers Andy

6

But pure WC still relies on accurate outside temp for choosing the correct flow temp?