Wintertime driving with a non working or cold car heater is not only no fun, inconvenient but downright deadly in colder climates and driving conditions. At least in the summer time driving season if your air conditioner does not work you don’t have frosted windows that do not defrost and your driving conditions are not hazardous and dangerous. In the winter if your car or trucks heater is tepid or blowing cold air through the auto heating system defrost your windows will never defrost. Worse yet as you drive the humidity and even the exhaust you exhale in your breath can fog up your windows in a flash. Disaster and a potential auto insurance collision claim or claims can be the result.
What are simple diagnostic steps both you and your mechanic can employ to resume the flow of hot air out of your passenger compartment heater and defroster.
First of all check that you have adequate engine coolant available.
Open the hood. Inspect the level of antifreeze in your radiator. In most cases you will not have to open the radiator cap directly. This can be somewhat dangerous on top of it, especially in a warm or hot engine and power plant cooling system. Under your hood, in most recent model car and trucks is an engine coolant recovery canister. On the side of the radiator will be an overflow coolant overflow tank. Note high and low markings – max and min. make sure that your fluid level is above the minimum making. (It may be marked min). In addition the markings may be for min – low and hot engine temperatures.
If you don’t have adequate coolant glycol antifreeze levels – even if you’re motor is running hot or warm there will not be enough coolant to flow into the engine heater and into the heater core in the passenger compartment inside the dash areas – to give you heat.
Your engine may be running fine – yet glycol / water coolant may have escaped or boiled in the warmer summer or long drive time periods leaving you with not enough fluids to flow into the heater core itself to give you good heat. Check rad fluid levels. If low top up – not with water but with ethylene glycol standard antifreeze solution. One simple jug of Prestone or whatever brand you purchase may solve all your problems and be just the trick you needed to get you on your way down the road toasty warm and with clear safe window visibility.
Next even if fluid levels in the radiator cooling system are fine have your antifreeze checked. You may be fine on fluid levels but have too low a mixture percentage of glycol antifreeze to water. Too low a percentage and your coolant may freeze up solid during the dead of winter resulting in dangerous & expensive engine block damage. True there are “frost plugs” in engine blocks to prevent damage but why chance the cost and inconvenience. Antifreeze coolant protection can be checked in a snap by your mechanic or even local garage grease monkey. If coolant level percentages and ratios are fine – water can be added, depending on the coldness of your local climate.
Use soft distilled water rather than tap water (which has dissolved minerals) to prevent scaling in your rad. Auto engine rads like kettles full of beach water lime scale don’t work well to keep cars cool – resulting in summer boils ups and poor winter car interior heat output levels.
Lastly if neither of the two above don’t work or even then just to be sure – have your mechanic take the thermostat out of your motor cooling system – inspect and test it.
Perhaps you need a replacement of the cooling system thermostat or perhaps a stronger winter one to give you better heat output from your car’s passenger area heater.
All the best and a good, warm & comfortable safe driving season to both yourself your family and friends this winter driving and motoring season. May the roads, highways and byways guide your holiday travels.
