Best thermistor for interior temperature?

[Umitbat]

Hi
Which is the best thermistor for interior temperature tuning?

 

[Pommie]

Tuning of what?

Mike.

 

[Umitbat]

For a car hvac system.
The problem is sensor is not saperate it is in the dash assy inside little vents.
The probe of sensor is gone so i need to put smt.
What value should i try?

 

[Wp100]

Probably it uses a bead type, but the value could be anything, you need to find its value from the workshop manual for you car .
Try enquring in the car makers users forum for such info.

 

[Umitbat]

Probably it uses a bead type, but the value could be anything, you need to find its value from the workshop manual for you car .
Try enquring in the car makers users forum for such info.

View attachment 122559
View attachment 122559

I could not find a value for that.
I will try and find best value that suits system.

 

[Wp100]

There are a wide range of thermistor values, which are produced when at 25 deg C.

As you can see my cars thermistor is probably a 2k2 one , but yours could be different, so you might have to try several thermistor values to find the right one, though you might find using a 50k multiturn pot a quicker way to find the right value for the themistor...

 

[Umitbat]

I think 10k is ok.
2k was blowing too cold 5 better and 10 seems good for short trial.

 

[Umitbat]

After measurments actual cabin temp is 2 degrees lower then set temp.
It is stable at all degrees like 22 is 20 and 26 is 24 in cabin.

 

[Wp100]

Sounds good, 2 degrees quiet accurate in car terms, probably more accurate than the original !

 

[Umitbat]

Maybe i will try with a 10% more value to see if it will be better.

 

[Wp100]

Maybe i will try with a 10% more value to see if it will be better.

Personally would not bother as: -
1. many thermometers, even digital ones can be +-1c out, just compare several together.
2. depends where in the cabin / air vent you measure the temp ?

Do not forget the NTC means Negative, so the higher the temp the lower its resistance.

If the next value NTC gives a swing too high the other way, you could try adding a 1k trimmer pot in series with the NTC, which might allow you to balance it better, but seems a lot of messy work for such a small difference.

 

[Umitbat]

Personally would not bother as: -
1. many thermometers, even digital ones can be +-1c out, just compare several together.
2. depends where in the cabin / air vent you measure the temp ?

Do not forget the NTC means Negative, so the higher the temp the lower its resistance.

If the next value NTC gives a swing too high the other way, you could try adding a 1k trimmer pot in series with the NTC, which might allow you to balance it better, but seems a lot of messy work for such a small difference.

You are right. It works fine. One side of me was actually just like your thoughts and the other was go play some more. I think this is ok. Thanks for nice answer.