Loading ...
Sorry, an error occurred while loading the content.

Re: [toyota-prius] heater power usage question

Expand Messages
  • Levi Smith
    For real intents, yes it s free. He s on the freeway so the engine is already running. I seriously doubt that he s using more heat than the engine is normally
    Message 1 of 10 , Nov 5, 2008
    • 0 Attachment
      For real intents, yes it's free.
      He's on the freeway so the engine is already running. I seriously doubt
      that he's using more heat than the engine is normally producing with the fan
      off and at highway speeds.

      It is true that the ICE is hugely inefficient and that's why there's excess
      heat in the first place. But that's not really his question.

      Levi

      On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle <riddlere@...>wrote:

      > It is not free. If you have thermal loss beyond what the ICE can
      > generate you will eventually use fuel to...generate heat. Any thermal loss
      > at all will cause the ICE to ignite no matter how slowly or carefully you
      > drive. I had seat heaters installed in mine for that exact reason. Only
      > reason for firing up the heat system now is to clear off the fog.
      >
      > K. B. Eric Riddle
      > 1983 GL1100i & CB1000C
      > 2005 Prius
      > 2007 HHR & 2004 Ion
      > Bellevue, Sarpy County, Nebraska
      >
      > --- On Wed, 11/5/08, b uj <buj94565@... <buj94565%40yahoo.com>>
      > wrote:
      >
      > From: b uj <buj94565@... <buj94565%40yahoo.com>>
      > Subject: [toyota-prius] heater power usage question
      > To: toyota-prius@yahoogroups.com <toyota-prius%40yahoogroups.com>
      > Date: Wednesday, November 5, 2008, 9:27 AM
      >
      >
      > while on the freeway, i get hot air flow through because of ram effect and
      > negative pressure...
      >
      > when the heater is set to hot and it is turned off...i presume i'm getting
      > free heat from the gas motor heat...not from the electric heating element...
      >
      > is this a correct assumption?? ?
      >
      > thx
      >
      > [Non-text portions of this message have been removed]
      >
      >
      >


      [Non-text portions of this message have been removed]
    • Patrick Wong
      Well - how much heat do you feel when the system is turned off? Since an electric pump is used to circulate engine coolant to the cabin heater core, if the
      Message 2 of 10 , Nov 5, 2008
      • 0 Attachment
        Well - how much heat do you feel when the system is turned off?
        Since an electric pump is used to circulate engine coolant to the
        cabin heater core, if the system is off the pump is probably also
        off; hence you may not get much cabin heating under those conditions.

        Whatever heating you do obtain when driving on level ground or uphill
        can be deemed essentially "free" since it results from waste heat
        generated by the ICE. However if you are coasting downhill, and the
        ICE cools down sufficiently to restart, then under those conditions
        cabin heating has some nominal cost.

        Patrick Wong

        --- In toyota-prius@yahoogroups.com, b uj <buj94565@...> wrote:
        >
        > while on the freeway, i get hot air flow through because of ram
        effect and negative pressure...
        >
        > when the heater is set to hot and it is turned off...i presume i'm
        getting free heat from the gas motor heat...not from the electric
        heating element...
        >
        > is this a correct assumption???
      • Karl
        I agree. The heat is free in that case. Usually, when I drive on the freeway, the LITTLE time I do, I turn the heat up, then turn it off before I get to the
        Message 3 of 10 , Nov 6, 2008
        • 0 Attachment
          I agree. The heat is free in that case.

          Usually, when I drive on the freeway, the LITTLE time I do, I turn
          the heat up, then turn it off before I get to the ramp.

          I can still feel the heat traveling into the car while approaching
          the lights. I managed to get the entire heating system hot because
          I needed to run the ICE for the entire two miles.

          The question is, because I got the entire heating system hot, will
          that cause the ICE to run less off the freeway, at least for a
          little while?

          --- In toyota-prius@yahoogroups.com, "Levi Smith" <LeviGSmith@...>
          wrote:

          > For real intents, yes it's free.
          > He's on the freeway so the engine is already running. I seriously
          doubt
          > that he's using more heat than the engine is normally producing
          with the fan
          > off and at highway speeds.
          >
          > It is true that the ICE is hugely inefficient and that's why
          there's excess
          > heat in the first place. But that's not really his question.
          >
          > Levi
          >
          > On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle
          <riddlere@...>wrote:
          >
          > It is not free. If you have thermal loss beyond what the ICE can
          > > generate you will eventually use fuel to...generate heat. Any
          thermal loss
          > > at all will cause the ICE to ignite no matter how slowly or
          carefully you
          > > drive. I had seat heaters installed in mine for that exact
          reason. Only
          > > reason for firing up the heat system now is to clear off the fog.
          > >
          > > K. B. Eric Riddle
          > > 1983 GL1100i & CB1000C
          > > 2005 Prius
          > > 2007 HHR & 2004 Ion
          > > Bellevue, Sarpy County, Nebraska
          > >
          > > --- On Wed, 11/5/08, b uj <buj94565@... <buj94565%40yahoo.com>>
          > > wrote:
          > >
          > > From: b uj <buj94565@... <buj94565%40yahoo.com>>
          > > Subject: [toyota-prius] heater power usage question
          > > To: toyota-prius@yahoogroups.com <toyota-prius%40yahoogroups.com>
          > > Date: Wednesday, November 5, 2008, 9:27 AM
          > >
          > >
          > > while on the freeway, i get hot air flow through because of ram
          effect and
          > > negative pressure...
          > >
          > > when the heater is set to hot and it is turned off...i presume
          i'm getting
          > > free heat from the gas motor heat...not from the electric
          heating element...
          > >
          > > is this a correct assumption?? ?
          > >
          > > thx
          > >
          > > [Non-text portions of this message have been removed]
          > >
          > >
          > >
          >
          >
          > [Non-text portions of this message have been removed]
          >
        • Gary Novosielski
          I think you misunderstood the question. If the Climate system is turned OFF, the heat is indeed free. The ICE will run to generate heat if the Climate system
          Message 4 of 10 , Nov 12, 2008
          • 0 Attachment
            I think you misunderstood the question. If the Climate system is turned
            OFF, the heat is indeed free.

            The ICE will run to generate heat if the Climate system is ON, but *not *if
            it's OFF.

            You can get a pretty large amount of free heat by turning the temp all the
            way up, and then turning the system OFF. You can still control the vent
            openings (foot is best) and of course make sure to set the air intake to
            outside, not re-circ.

            But after that the heat is free, and fairly substantial at highway speeds.
            In city traffic it probably won't be enough to keep you warm, and since the
            engine will spend a lot of time not running, things cool off rapidly.

            =Gary


            On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle <riddlere@...>wrote:

            > *It is not free. If you have thermal loss beyond what the ICE can
            > generate you will eventually use fuel to...generate heat. Any thermal loss
            > at all will cause the ICE to ignite no matter how slowly or carefully you
            > drive. I had seat heaters installed in mine for that exact reason. Only
            > reason for firing up the heat system now is to clear off the fog.
            > *
            >


            [Non-text portions of this message have been removed]
          • Lawrence D. Lopez
            By way of comparison: A VW Golf Diesel provides very little heat when at idle. It doesn t shut down the engine. In fact it has heaters in the water jacket to
            Message 5 of 10 , Nov 13, 2008
            • 0 Attachment
              By way of comparison:

              A VW Golf Diesel provides very little heat when at idle.
              It doesn't shut down the engine.
              In fact it has heaters in the water jacket to get the engine up to
              operating temperature.
              It burns so little fuel that it don't get up to operating temperature
              otherwise.

              A Prius at idle & AC off provides no heat.
              But it still has to cycle the engine to keep the catalytic heater hot
              and the traction battery topped up.
              A prius at idle & AC on and heat set very low might make sense I suppose.

              Does anyone have an idea how much fuel we are talking about ?

              Is this what is dropping the MPG in winter ?

              I could start wearing my coat but it isn't really winter yet.




              Gary Novosielski wrote:
              >
              > I think you misunderstood the question. If the Climate system is turned
              > OFF, the heat is indeed free.
              >
              > The ICE will run to generate heat if the Climate system is ON, but
              > *not *if
              > it's OFF.
              >
              > You can get a pretty large amount of free heat by turning the temp all the
              > way up, and then turning the system OFF. You can still control the vent
              > openings (foot is best) and of course make sure to set the air intake to
              > outside, not re-circ.
              >
              > But after that the heat is free, and fairly substantial at highway speeds.
              > In city traffic it probably won't be enough to keep you warm, and
              > since the
              > engine will spend a lot of time not running, things cool off rapidly.
              >
              > =Gary
              >
              > On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle <riddlere@...
              > <mailto:riddlere%40yahoo.com>>wrote:
              >
              > > *It is not free. If you have thermal loss beyond what the ICE can
              > > generate you will eventually use fuel to...generate heat. Any
              > thermal loss
              > > at all will cause the ICE to ignite no matter how slowly or
              > carefully you
              > > drive. I had seat heaters installed in mine for that exact reason. Only
              > > reason for firing up the heat system now is to clear off the fog.
              > > *
              > >
              >
              > [Non-text portions of this message have been removed]
              >
              >
            • GREGMCKAY@aol.com
              I am not looking at the display right now, but I know there are conditions or situations where the temperature controls are not available to adjust.? I assume
              Message 6 of 10 , Nov 13, 2008
              • 0 Attachment
                I am not looking at the display right now, but I know there are conditions or situations where the temperature controls are not available to adjust.? I assume that this is when the system is actually OFF.??? If that is the case, how does what you describe work??


                -----Original Message-----
                From: Gary Novosielski <gary.novosielski@...>
                To: riddlere@...
                Cc: toyota-prius@yahoogroups.com; buj94565@...
                Sent: Wed, 12 Nov 2008 11:46 pm
                Subject: Re: [toyota-prius] heater power usage question






                I think you misunderstood the question. If the Climate system is turned
                OFF, the heat is indeed free.

                The ICE will run to generate heat if the Climate system is ON, but *not *if
                it's OFF.

                You can get a pretty large amount of free heat by turning the temp all the
                way up, and then turning the system OFF. You can still control the vent
                openings (foot is best) and of course make sure to set the air intake to
                outside, not re-circ.

                But after that the heat is free, and fairly substantial at highway speeds.
                In city traffic it probably won't be enough to keep you warm, and since the
                engine will spend a lot of time not running, things cool off rapidly.

                =Gary

                On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle <riddlere@...>wrote:

                > *It is not free. If you have thermal loss beyond what the ICE can
                > generate you will eventually use fuel to...generate heat. Any thermal loss
                > at all will cause the ICE to ignite no matter how slowly or carefully you
                > drive. I had seat heaters installed in mine for that exact reason. Only
                > reason for firing up the heat system now is to clear off the fog.
                > *
                >

                [Non-text portions of this message have been removed]






                [Non-text portions of this message have been removed]
              • Lawrence D. Lopez
                I do this: turn AC on. set heat to max. wait a few seconds for this to happen. turn AC off. This seems to provide ram air induced heat. I suspect it opens the
                Message 7 of 10 , Nov 13, 2008
                • 0 Attachment
                  I do this:

                  turn AC on.
                  set heat to max.
                  wait a few seconds for this to happen.
                  turn AC off.

                  This seems to provide ram air induced heat.

                  I suspect it opens the air valve for the heater core and lets air flow
                  into it.

                  This heat is only free if the engine doesn't need more heat.

                  Driving at 60 MPH at -20 would not be this situation as you might very
                  well too much heat from the engine.
                  At this point you would need to block your radiator.
                  Seems to me I was doing with a previous Prius.


                  GREGMCKAY@... wrote:
                  >
                  > I am not looking at the display right now, but I know there are
                  > conditions or situations where the temperature controls are not
                  > available to adjust.? I assume that this is when the system is
                  > actually OFF.??? If that is the case, how does what you describe work??
                  >
                  > -----Original Message-----
                  > From: Gary Novosielski <gary.novosielski@...
                  > <mailto:gary.novosielski%40gmail.com>>
                  > To: riddlere@... <mailto:riddlere%40yahoo.com>
                  > Cc: toyota-prius@yahoogroups.com
                  > <mailto:toyota-prius%40yahoogroups.com>; buj94565@...
                  > <mailto:buj94565%40yahoo.com>
                  > Sent: Wed, 12 Nov 2008 11:46 pm
                  > Subject: Re: [toyota-prius] heater power usage question
                  >
                  > I think you misunderstood the question. If the Climate system is turned
                  > OFF, the heat is indeed free.
                  >
                  > The ICE will run to generate heat if the Climate system is ON, but
                  > *not *if
                  > it's OFF.
                  >
                  > You can get a pretty large amount of free heat by turning the temp all the
                  > way up, and then turning the system OFF. You can still control the vent
                  > openings (foot is best) and of course make sure to set the air intake to
                  > outside, not re-circ.
                  >
                  > But after that the heat is free, and fairly substantial at highway speeds.
                  > In city traffic it probably won't be enough to keep you warm, and
                  > since the
                  > engine will spend a lot of time not running, things cool off rapidly.
                  >
                  > =Gary
                  >
                  > On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle <riddlere@...
                  > <mailto:riddlere%40yahoo.com>>wrote:
                  >
                  > > *It is not free. If you have thermal loss beyond what the ICE can
                  > > generate you will eventually use fuel to...generate heat. Any
                  > thermal loss
                  > > at all will cause the ICE to ignite no matter how slowly or
                  > carefully you
                  > > drive. I had seat heaters installed in mine for that exact reason. Only
                  > > reason for firing up the heat system now is to clear off the fog.
                  > > *
                  > >
                  >
                  > [Non-text portions of this message have been removed]
                  >
                  > [Non-text portions of this message have been removed]
                  >
                  >
                • Karl
                  When its cold, I do take a quick 2 mile trip on the highway and turn up the fan to warm the interior. (My drive to work is in the dark) I also turn off the fan
                  Message 8 of 10 , Nov 13, 2008
                  • 0 Attachment
                    When its cold, I do take a quick 2 mile trip on the highway and turn
                    up the fan to warm the interior. (My drive to work is in the dark)
                    I also turn off the fan before I get off the throttle to exit.

                    Why do you say "foot is best"? Personally, I feel the people inside
                    benefit more from floor and dash. Plus foot is actually foot and
                    defrost.

                    Also, defrost is something I recommend avoiding all-together, unless
                    you need it.

                    A warm windshield melts snow (in places where you get it) to where
                    the water rolls down to the (below 32) windshield wiper blades, to
                    where it freezes. When the temp is below freezing, you have to warm
                    the glass enough to warm the blades, and that takes a lot in any
                    vehicle, let alone one that doesn't normally generate much heat.

                    --- In toyota-prius@yahoogroups.com, "Gary Novosielski"
                    <gary.novosielski@...> wrote:
                    >
                    > I think you misunderstood the question. If the Climate system is
                    turned
                    > OFF, the heat is indeed free.
                    >
                    > The ICE will run to generate heat if the Climate system is ON, but
                    *not *if
                    > it's OFF.
                    >
                    > You can get a pretty large amount of free heat by turning the temp
                    all the
                    > way up, and then turning the system OFF. You can still control
                    the vent
                    > openings (foot is best) and of course make sure to set the air
                    intake to
                    > outside, not re-circ.
                    >
                    > But after that the heat is free, and fairly substantial at highway
                    speeds.
                    > In city traffic it probably won't be enough to keep you warm, and
                    since the
                    > engine will spend a lot of time not running, things cool off
                    rapidly.
                    >
                    > =Gary
                    >
                    >
                    > On Wed, Nov 5, 2008 at 10:31 AM, K. B. Eric Riddle
                    <riddlere@...>wrote:
                    >
                    > > *It is not free. If you have thermal loss beyond what the ICE
                    can
                    > > generate you will eventually use fuel to...generate heat. Any
                    thermal loss
                    > > at all will cause the ICE to ignite no matter how slowly or
                    carefully you
                    > > drive. I had seat heaters installed in mine for that exact
                    reason. Only
                    > > reason for firing up the heat system now is to clear off the fog.
                    > > *
                    > >
                    >
                    >
                    > [Non-text portions of this message have been removed]
                    >
                  Your message has been successfully submitted and would be delivered to recipients shortly.