Gary,
If the internal temperature is higher than the setting, why would the heater core be putting in warm air? To my mind I think that it would only be putting heat in if the cabin temp was LESS than the setting. Am I missing something?

BTW, I think my wife would prefer that our 2008 had the 2009 settings. She is always turning off the ECON in hot weather, even at a short stop light.

 

No, your right that heat though the blend door would be supplied if the cabin was lower only. My point was that the A/C compressor can continue to run and the temperature would be adjusted with heated air at the higher setting. A heater core bypass would solve this problem but screw-up the auto A/C regulation.

My '05 has the manual system and I did a heater core bypass in it to keep the cabin cooler longer while in EV. Also, the cabin can get colder faster with a cold heater core.

My wife also likes the '09 better because she set the temp. (72F) so the engine will never shutdown for EV in the ECON mode. She even runs MAX A/C in the '05 year round. When it gets to cold in the cabin, she just turns the fan on low and adjusts the temperature setting. She never complained that the heater didn't work (core bypass) at all this winter so I did not say anything about that.

GaryG

 

Question from a potential 09 FEH buyer. I currently own 07 TCH and love it. Has electric compressor. Want to add a 4cyl Hybrid SUV to the stable..the only real choice I see is the 2009 FEH. I live in Tucson, which is over 100 degrees from June till October.

Ok. Here's the question... Will I roast with the FEH at stop lights? From reading this thread, it seems that A/C will run if engine is on...I expect this will be the usual, as short trips with sun heated car = hot interior. How bad will economy suffer durung the summer here? It seems running the engine at stops is counter to the Hybrid premise...Better to get a Non Hybrid SUV? Thanks for thoughful input.

 

The 2009 FEH runs the engine regardless of ECON mode settings, based on the temperature you set in the HVAC controls. Basically, the software will not shut down the engine unless the interior temperature is within a certain range of the set temperature.

2008 and previous FEH followed the ECON button; if it was turned on, then the engine shut down when possible, such as at stops, unless the battery needed A/C.

 

I think this might of been covered in another post. But the 09 FEH does have A/C lines running to the hv batt. I've posted some pix of the under side of my 09.
Found one!


As far as the whole Econ button goes I do like knowing what temp it is in my FEH.

 

Thanks, I corrected my original post. I'm always a bit hesitant to list stuff from the 2009 (I own the 2008), but we went over this before the 2009 came out... I guess I missed that one. Personally, I like the fact that they are providing A/C to the battery pack.

RE:Econ mode. I prefer the 2008 method. If I want to know what temperature is inside my FEH, I'll get a thermometer. FWIW, you don't know what the inside temp is with the 2009, if my understanding is correct; you only know the temperature is somewhere above the temperature you set (possibly within a couple of degrees if the engine is shutting off).

Perhaps one could say it is a moot point, since I'd probably be running the A/C on NON ECON if it is that hot inside the vehicle. But I like to be able to control the engine cutoff.

 

Without looking at the books (a bit distant from me for the moment):

The econ button does more than A/c. I believe it changes, though this may not be all, engine timing and such. Specifically: best power occurs at an Air to fuel ratio of about 12.5:1 while best economy occurs at an A/f ratio of about 14.7:1.

I have no question that implementation of effective strategies with regard to A/C will be part of an "Econ" button. But understand that the engine itself does have a "Best Power" & a "Best Economy" inherent in the Otto cycle (or Atkinson Cycle) and in its timing and point of ignition.

I believe that clearly Ford has included such things as A/C strategy in such a button.

 

If you want to control the engine shut off similar to the 08, then just shut off the A/C button (with the econ button lit) and the engine will shut right off....

If you don't mind baking at a light because it is getting ridiculously hot inside, what I just typed is an option...

I have had both the 08 and the 09 FEH and in the 08, when I got smoking hot at a light, I too would shut off the econ so that the ice would start and cool me down...

What I like about the 09 is that when the econ is on, the ice will shut down at a stop sign, and right about the time that I would be shutting off the econ (in my 08), the 09 software kicks in and starts the ice because it senses the BIG difference between my climate control setting and the actual interior temp..

If the software starts the ice by overiding the econ and I don't want the ice running, I just push the A/C button (shutting the a/c off) and the ICE shuts right back down.

hope the info helps!

Sean...

 

Good point. But I think I still prefer the 2008, because you have to manually restart the A/C when you drive off under your proposal.

I'm wondering why Ford didn't provide display of the interior temperature, since they obviously measure it.

Does anyone know exactly how far off the actual vs. set temperature has to be for the A/C to shut off in the 2009?

 

I'll know more about the '09 FEH system by the end of the summer but what I see is the interior dual setting temperatures and outside temperature only. The ECON mode lets the engine and A/C shutdown when the inside temperature setting matches the outside temperature. If the outside temperature is warmer than the settings, it only takes a second to kick the engine and compressor on again. This is fine for people who can't take the warming of the cabin a little and don't care about long EV driving. An extreme hypermiler may fine this system useless and prefer the older FEH ECON system. With all the glass and lack of insulation, the cabin temperature climbs too quick for the '09 system for me. It's fine at 71-72 degrees or below outside and raining and need to defog the windshield.

I don't think the ECON mode has anything to do with engine A/F ratios though.

GaryG