Advice sensors humidity and temperature

Hello, I live in a zone by the sea where there is a high humidity.
Temperatures are around 10 in winter and 35-40 in summer.
I need some advice on the temperature and humidity sensors inside the house.
Those that have htu21d or bme280 do not work well for humidity.
The humidity is 75, 85% without ventilation or heating inside the house and htu21d or bme280 score 69, 68.
As far as temperature is right on both sensors.
I do not know if it’s due to condensation or something else I can not figure out.
That’s why I need advice on which sensors to use.
Which sensors advise me, which are not extra costly to use with esp8266, mini wemos.
Thank you.

The humidity is 75, 85% without ventilation or heating inside the house and htu21d or bme280 score 69, 68.

What device gave you the reference measurements? BME280 usually won’t be off the actual value by more than about 5%RH even if in conditions with a high humidity. Inhouse measurements are usually not condensing, so the accuracy mentioned in the datasheet should still apply.

Condensation occurs at the dew point You can create a calibration device with a circulator pup and some water Put in your water and let sit to acquire room temperature Circulate Add colder water to have the temper drop a degree at a time. Watch for condensation Water temperature and condensation occur at the dew point There are tables to show the relative himidity

Condensation occurs at the dew point

And the dew point is defined to be 100%RH. What does that help in this regard? OP doesn't have 100%RH but about 80%, at least some unspecified reference device is telling him that.

pylon: And the dew point is defined to be 100%RH. What does that help in this regard? OP doesn't have 100%RH but about 80%, at least some unspecified reference device is telling him that.

I gave him the specified reference for determining the RH. if your room is 72 deg F humidity is unknown. You take a metal container of water in the room (cooking pot?) and the water is about room temperature. you add a cup of cold water and stir. The water temperature will decrease as will the metal of the vessel Watch the mixed water temperature and the room temperature. say, you keep adding cold until you see the water on the metal start to condense. That means the walls of the container are below the dew point Room at 72, say the water temperature drops to 64. degrees and you see condensation then you know that the RH is 76% The slower you can drop the water temperature and the more accurate you can verify the presence of condensation, the more accurate your tests will be. I am pretty sure you have to allow for altitude. so, I laid out a way to verify dew point in a non condensing atmosphere. very easy to determine within a few % of relative humidity. another way : you can get matched and calibrated thermometers put a sock over one and wet it with distilled water. blow air over them and the evaporation of the water will lower the temperature of the wet sock and the thermometer once the temperature stabilizes, you have two temperatures with that you can solve for humidity. said device is a psychrometer.