At what ambient temp is thermostat fully open?
- Thread starter zach1900
- Start date
- Status
The thermostat is what is used to control the coolant temps in an engine . the thermostat common numbers are 160* to 210* depending on the engine . So if the ambient temps were 160* to 210* depending on the engine the thermostats would be open .
what CY8 said
Depends. Ford gives specs for both initial open and fully open in the shop manuals.
Last edited:
To be specific: thermostats used in water-cooled IC engines sense the coolant temperature, not the ambient (atmospheric) temp.
So, unless your ambient temperature manages to get to the point where the coolant within your engine would be sufficiently high to open the thermostat (some as low as 178F), otherwise: no, you won't see that happening to a thermostat inside a water-cooled engine.
*smiles*
Q.
So, unless your ambient temperature manages to get to the point where the coolant within your engine would be sufficiently high to open the thermostat (some as low as 178F), otherwise: no, you won't see that happening to a thermostat inside a water-cooled engine.
*smiles*
Q.
For cars that have a radiator cap you can start it with the cap off and watch for flow to begin (ie when the t-stat opens). When the flow stops increasing, it's essentially full open. A quality thermometer or infra red gun can tell you the water temp at that point.
The thermostat rating (stamped on the bottom) is the temperature it is designed to start opening at. The T-stat is generally fully open at a temp that is a little higher than rated.
For example on my Regal the stock T-stat is a 195 and the low fans come on at 212. Watching live date the coolant will stay around 202-205 driving around town with moderate wait times at lights or stop signs.
For example on my Regal the stock T-stat is a 195 and the low fans come on at 212. Watching live date the coolant will stay around 202-205 driving around town with moderate wait times at lights or stop signs.
If it's a 180° outside.....you won't have to worry about the thermostat opening.
If the t-stat opens at ambient temp, that means the t-stat is bad.
I am assuming this is for a vehicle or a machine.
If this is the t-stat at your house for the HVAC system, then it should open at whatever temp specified by the user or close to that value.
I am assuming this is for a vehicle or a machine.
If this is the t-stat at your house for the HVAC system, then it should open at whatever temp specified by the user or close to that value.
Last edited:
Originally Posted By: zach1900
Above freezing?
Yes, definitely above freezing.
Above freezing?
Yes, definitely above freezing.
There's no defined ambient temp where the t-stat is fully open. We'll use my Jeep as an example. It has a 195* t-stat, so it begins to open at 195* coolant temp and is fully open at 210 - 215* coolant temp.
If I let it idle with the cooling fan on in 80* weather, the t-stat is barely open to keep up with cooling demands and the coolant temp sits right around 195 - 200*.
However, if it's 30* outside and I'm dragging a trailer up the side of a mountain standing on the throttle, it's producing a lot more heat than the first scenario. Even though the radiator is more effective due to the colder outside air, it'll still have the t-stat open most of the way and the coolant temp up around 210* in this situation.
If I let it idle with the cooling fan on in 80* weather, the t-stat is barely open to keep up with cooling demands and the coolant temp sits right around 195 - 200*.
However, if it's 30* outside and I'm dragging a trailer up the side of a mountain standing on the throttle, it's producing a lot more heat than the first scenario. Even though the radiator is more effective due to the colder outside air, it'll still have the t-stat open most of the way and the coolant temp up around 210* in this situation.
Originally Posted By: philipp10
the key word here is ambient. Ambient being the air temperature the car is exposed to. There is no way to tell you when the thermostat will open by ambient temperature.
+1. It's a nice word but it doesn't apply here. Thermostats are controlled by engine temperature, to test one you need to put it in water and heat it to close to boiling, 200 + F unless you're on a mountain.
the key word here is ambient. Ambient being the air temperature the car is exposed to. There is no way to tell you when the thermostat will open by ambient temperature.
+1. It's a nice word but it doesn't apply here. Thermostats are controlled by engine temperature, to test one you need to put it in water and heat it to close to boiling, 200 + F unless you're on a mountain.
203 F for my 04 Camry V6 per the shop manual.
Ambient temperature is what you feel when you walk outside your house or what ever your in and then go out.
The thermostat will never open in ambient temperature. If it does its broken.
The thermostat will never open in ambient temperature. If it does its broken.
- Status
Similar threads
