sk47
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Mechanic Explains Why Your Heater Shouldn't Be on 'Full Blast' When You Start Your Car
Hello; Have had a similar discussion with a "know it all" as old as I am. Perhaps the sort who gives unsolicited advice. We were in my vehicle on a very cold day. I had the heat knob turned over to the hottest setting and the fan off. He decided to tell me I was doing it wrong. That I should keep the heat setting to cold until after the engine warmed up some.
His being old like myself is a key to why he is wrong in my opinion. We both grew up in the 1950's-60's. His understanding of what happens under the hood had stalled back a few decades. Back in the day coolant/heat systems had shutoff valves which controlled the flow of radiator coolant into the heater. You closed the valve in warm weather to keep hot coolant out of the passenger compartment. Opened the valve to get hot coolant into the heater core.
For some time back then, I lacked funds to replace such a valve on a 57 Chevy. So, I would run a heater hose to the heater fittings on the firewall during cold weather. Then when it got to warm weather, I would loop the heater hose back into fittings on the water pump. Made spring and fall a time of not enough heat or too much heat some days depending on the way the hoses were run.
Back to the story. Newer vehicles have for a long time done away with such valves. now there is coolant constantly flowing into the heater cores. The heater cores become in a sense a second radiator. Getting heat in or keeping heat out of the cabin is done by a box around the heater core, with the box having "blend" doors. The blend doors can open or close in a pattern which sends the heated air to inside or to the outside of the car.
My contention being the heat control knob may as well be all the way to the hottest setting from a cold engine start. I keep the fan off for a time until the engine begins to warm up some, then turn on the fan.
Comments????
Hello; Have had a similar discussion with a "know it all" as old as I am. Perhaps the sort who gives unsolicited advice. We were in my vehicle on a very cold day. I had the heat knob turned over to the hottest setting and the fan off. He decided to tell me I was doing it wrong. That I should keep the heat setting to cold until after the engine warmed up some.
His being old like myself is a key to why he is wrong in my opinion. We both grew up in the 1950's-60's. His understanding of what happens under the hood had stalled back a few decades. Back in the day coolant/heat systems had shutoff valves which controlled the flow of radiator coolant into the heater. You closed the valve in warm weather to keep hot coolant out of the passenger compartment. Opened the valve to get hot coolant into the heater core.
For some time back then, I lacked funds to replace such a valve on a 57 Chevy. So, I would run a heater hose to the heater fittings on the firewall during cold weather. Then when it got to warm weather, I would loop the heater hose back into fittings on the water pump. Made spring and fall a time of not enough heat or too much heat some days depending on the way the hoses were run.
Back to the story. Newer vehicles have for a long time done away with such valves. now there is coolant constantly flowing into the heater cores. The heater cores become in a sense a second radiator. Getting heat in or keeping heat out of the cabin is done by a box around the heater core, with the box having "blend" doors. The blend doors can open or close in a pattern which sends the heated air to inside or to the outside of the car.
My contention being the heat control knob may as well be all the way to the hottest setting from a cold engine start. I keep the fan off for a time until the engine begins to warm up some, then turn on the fan.
Comments????
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