Coolant Thermostat: Buy Online & Save!

Hello.

A new question I would like to ask is:

'I've noticed that when driving my car (about 10 km) in these outside temperatures (5 degrees Celsius or higher), alternating between city streets and highway (maximum 100 km/h), the coolant hose leading to the thermostat isn't getting properly warm! However, all the other hoses are at operating temperature, and the temperature gauge in the car shows 90 degrees Celsius or higher. Also, the heater gets hot when I turn it up.'

Now, to my question: Is it normal for the lower coolant hose to be colder than all the other hoses at these temperatures?
Is this due to the large radiator?

Volkswagen Golf III TD, manufactured in 1997, engine code: AAZ, 1.9L.

Thank you and best regards, Mark .

P.S. A friend of mine is experiencing the same issue. He has an Opel Astra 1.7 TD.

The lower coolant hose connecting the radiator to the engine (thermostat) should remain cold (except for heat radiating from the engine). Most of the energy is used for the heat exchanger inside the vehicle, and the large cooling circuit (through the front radiator) should not be activated, therefore it should also remain cold.

The thermostat only opens and allows coolant to flow through the radiator to provide additional cooling when the coolant temperature exceeds approximately 92°C (I don't know the exact value for your specific engine).

Hello.
Thank you for your help.


Best, Mark.