The blend door idea is a good one. Make sure all the HVAC doors are working properly. This may be difficult to do without major disassembly, however. In have used one of those USB snake cameras plugged into my phone in the past to check out the internals.
A/C & hot weather question....
- Thread starter badtlc
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Originally Posted By: badtlc
Originally Posted By: Kuato
Something people often fail to account for is that your vehicle has been in the sun. The interior keeps radiating heat for quite awhile after you start it, so having the windows open 1/2" at the top lets the heat escape, so it does feel cooler with windows up. Hot air rises....
Once the interior cools down, then the AC has a chance to catch up. If you're doing a long highway trip it will be hot once. If you're doing a bunch of stuff around town, or just commuting, it will probably be hot all day. It's a question of capacity of the system - it can't cool both the existing air AND all the interior surfaces right away.
A 30° reduction from OAT is pretty good. You could increase the efficiency of your system by insulating the cold side of the AC system under the hood, if it isn't already insulated.
I think this might be part of it but I wanted to make sure I have eliminated any other possibilities. If this is the main culprit, might be time to get some window tinting done and a clear film on the windshield. I just want to make sure before shelling out $ for something that might not help.
One of the reflective setups inside the windshield helps a lot....
Originally Posted By: Kuato
Something people often fail to account for is that your vehicle has been in the sun. The interior keeps radiating heat for quite awhile after you start it, so having the windows open 1/2" at the top lets the heat escape, so it does feel cooler with windows up. Hot air rises....
Once the interior cools down, then the AC has a chance to catch up. If you're doing a long highway trip it will be hot once. If you're doing a bunch of stuff around town, or just commuting, it will probably be hot all day. It's a question of capacity of the system - it can't cool both the existing air AND all the interior surfaces right away.
A 30° reduction from OAT is pretty good. You could increase the efficiency of your system by insulating the cold side of the AC system under the hood, if it isn't already insulated.
I think this might be part of it but I wanted to make sure I have eliminated any other possibilities. If this is the main culprit, might be time to get some window tinting done and a clear film on the windshield. I just want to make sure before shelling out $ for something that might not help.
One of the reflective setups inside the windshield helps a lot....
be sure you HEATER valve cuts off the hot water to the heater core
Originally Posted By: edwardh1
be sure you HEATER valve cuts off the hot water to the heater core
You beat me to it. When the ac is set to MAX AC, the control head or similar should send vacuum to the heater control valve to close off hot water flow to the heater core. If it's inoperative check for a stuck valve or lack of vacuum to the valve due to missing or damaged vac hose. I've got an Explorer in the shop now that relies on a linkage to press a detent which applies vacuum to the valve- and I think the linkage is broken.
be sure you HEATER valve cuts off the hot water to the heater core
You beat me to it. When the ac is set to MAX AC, the control head or similar should send vacuum to the heater control valve to close off hot water flow to the heater core. If it's inoperative check for a stuck valve or lack of vacuum to the valve due to missing or damaged vac hose. I've got an Explorer in the shop now that relies on a linkage to press a detent which applies vacuum to the valve- and I think the linkage is broken.
Originally Posted By: edwardh1
be sure you HEATER valve cuts off the hot water to the heater core
Wouldn't this cause vent air to be warm? When I run the vent, i get similar temps to outside air. Very little heat rise. I think the heat is completely off.
Blending dampers have been checked. No issues there. Floor, pane, defrost, all working fine and closing when on other settings.
This is an old fashioned manual system for those that weren't aware. Nothing that I can calibrate as far as climate control settings go.
be sure you HEATER valve cuts off the hot water to the heater core
Wouldn't this cause vent air to be warm? When I run the vent, i get similar temps to outside air. Very little heat rise. I think the heat is completely off.
Blending dampers have been checked. No issues there. Floor, pane, defrost, all working fine and closing when on other settings.
This is an old fashioned manual system for those that weren't aware. Nothing that I can calibrate as far as climate control settings go.
When it's this hot, it seemingly never works good enough.
Most cars no longer have heater core valves but rather have full flow going through the heater core all the time. This is to eliminate problems like Ford had with the 3.0L Vulcan.
They use a blend door in the heater box under the dash to mix cold and hot air.
They use a blend door in the heater box under the dash to mix cold and hot air.
Originally Posted By: SHOZ
Most cars no longer have heater core valves but rather have full flow going through the heater core all the time. This is to eliminate problems like Ford had with the 3.0L Vulcan.
They use a blend door in the heater box under the dash to mix cold and hot air.
If this isn't working right, wouldn't outside vent air settings be noticeably warmer than ambient temps?
Most cars no longer have heater core valves but rather have full flow going through the heater core all the time. This is to eliminate problems like Ford had with the 3.0L Vulcan.
They use a blend door in the heater box under the dash to mix cold and hot air.
If this isn't working right, wouldn't outside vent air settings be noticeably warmer than ambient temps?
Normal! For the Escape's anyways. The only complaint my wife has about ours. Everything is charged perfect. Tinted windows? Also I've wrapped our ac lines in pipe insulation and if you have a filter make sure it's clean.
The low pressure line in my 2012 Mazda3 is totally bare for 2-3 feet under the hood. At one point I did wrap it in some cork HVAC tape. I later learned that I was wasting my time and that there could be negative consequences for doing so. I thought I learned that on BITOG, but I can't remember. I removed the tape. The air comes out of my vents at something like 42 degrees, which is as good as it can be. There is so much windshield that the air that actually hits me has warmed while traveling that two feet. I have been considering a clear IR blocking film on the inside of the windshield. It is totally legal here, but it costs about $250. I'm also concerned about creating any visual aberrations and the tint film's long term durability.
Has anyone done that? There are tint films you can get now that are clear, or very light, that block IR as well as UV. Blocking UV and visible light does not cut the heat anywhere near as much as the IR blocking film.
Has anyone done that? There are tint films you can get now that are clear, or very light, that block IR as well as UV. Blocking UV and visible light does not cut the heat anywhere near as much as the IR blocking film.
Use recirculate until the air coming out of the vents is cool to the touch.
Either that, or your heater core control is broken and is allowing hot coolant to circulate through when it should be closed off.
Check your car's forums for a better answer.
Either that, or your heater core control is broken and is allowing hot coolant to circulate through when it should be closed off.
Check your car's forums for a better answer.
Originally Posted By: badtlc
I have a 2007 Escape. When it gets above 85F outside, it has a real hard time cooling down the interior. When I hit 90F+, it is cooler to roll windows down sadly. My shop says all the pressures read good and the delta between outside air and inside when using fresh air intake A/C setting is close to 30F. The problem is the day they tested it was cooler than 80F outside.
So, my question is, could there be an issue where an AC performs normal at lower ambient temps but not at higher temps due to higher pressures that don't indicate problems at lower temps?
Somethings wrong...here with 100°F ambient temps + 55% Rh, the sled A/C will blow 38°F air on recirc, even with fan set on MAX. That's for a white wagon with lots of glass. I do have 3M metal IR film all around. Sure makes a difference. The point is my delta-T is much higher than yours....on an 18 yr. old original A/C system too boot.
Your pressure line should be hot and the suction line cold & sweating. Condensor/radiator fan working? Blocked cabin air filter? Weak blower motor? Other obstruction blocking air flow to evap. core?
Mist the condensor and see if the vent temp. drops. IF so, that's a clue.
I have a 2007 Escape. When it gets above 85F outside, it has a real hard time cooling down the interior. When I hit 90F+, it is cooler to roll windows down sadly. My shop says all the pressures read good and the delta between outside air and inside when using fresh air intake A/C setting is close to 30F. The problem is the day they tested it was cooler than 80F outside.
So, my question is, could there be an issue where an AC performs normal at lower ambient temps but not at higher temps due to higher pressures that don't indicate problems at lower temps?
Somethings wrong...here with 100°F ambient temps + 55% Rh, the sled A/C will blow 38°F air on recirc, even with fan set on MAX. That's for a white wagon with lots of glass. I do have 3M metal IR film all around. Sure makes a difference. The point is my delta-T is much higher than yours....on an 18 yr. old original A/C system too boot.
Your pressure line should be hot and the suction line cold & sweating. Condensor/radiator fan working? Blocked cabin air filter? Weak blower motor? Other obstruction blocking air flow to evap. core?
Mist the condensor and see if the vent temp. drops. IF so, that's a clue.
Originally Posted By: sleddriver
Originally Posted By: badtlc
I have a 2007 Escape. When it gets above 85F outside, it has a real hard time cooling down the interior. When I hit 90F+, it is cooler to roll windows down sadly. My shop says all the pressures read good and the delta between outside air and inside when using fresh air intake A/C setting is close to 30F. The problem is the day they tested it was cooler than 80F outside.
So, my question is, could there be an issue where an AC performs normal at lower ambient temps but not at higher temps due to higher pressures that don't indicate problems at lower temps?
Somethings wrong...here with 100°F ambient temps + 55% Rh, the sled A/C will blow 38°F air on recirc, even with fan set on MAX. That's for a white wagon with lots of glass. I do have 3M metal IR film all around. Sure makes a difference. The point is my delta-T is much higher than yours....on an 18 yr. old original A/C system too boot.
Your pressure line should be hot and the suction line cold & sweating. Condensor/radiator fan working? Blocked cabin air filter? Weak blower motor? Other obstruction blocking air flow to evap. core?
Mist the condensor and see if the vent temp. drops. IF so, that's a clue.
Taking temps measurements on recirc doesn't provide you any useful data. The coils are designed to provide a specific delta-T which is the difference between outside temp and supply air. to get that measurement, you have to be running outside air across the coils and recirc setting doesn't do that.
Originally Posted By: badtlc
I have a 2007 Escape. When it gets above 85F outside, it has a real hard time cooling down the interior. When I hit 90F+, it is cooler to roll windows down sadly. My shop says all the pressures read good and the delta between outside air and inside when using fresh air intake A/C setting is close to 30F. The problem is the day they tested it was cooler than 80F outside.
So, my question is, could there be an issue where an AC performs normal at lower ambient temps but not at higher temps due to higher pressures that don't indicate problems at lower temps?
Somethings wrong...here with 100°F ambient temps + 55% Rh, the sled A/C will blow 38°F air on recirc, even with fan set on MAX. That's for a white wagon with lots of glass. I do have 3M metal IR film all around. Sure makes a difference. The point is my delta-T is much higher than yours....on an 18 yr. old original A/C system too boot.
Your pressure line should be hot and the suction line cold & sweating. Condensor/radiator fan working? Blocked cabin air filter? Weak blower motor? Other obstruction blocking air flow to evap. core?
Mist the condensor and see if the vent temp. drops. IF so, that's a clue.
Taking temps measurements on recirc doesn't provide you any useful data. The coils are designed to provide a specific delta-T which is the difference between outside temp and supply air. to get that measurement, you have to be running outside air across the coils and recirc setting doesn't do that.
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What color are your car and upholstery? One of my cars has a black interior and if I forget to put the windshield sun visor on, the inside burns for ages, even with the A/C blasting and windows cracked. With the visor, the inside becomes pleasant in a couple of minutes.
Last edited:
Originally Posted By: badtlc
Originally Posted By: edwardh1
be sure you HEATER valve cuts off the hot water to the heater core
Wouldn't this cause vent air to be warm? When I run the vent, i get similar temps to outside air. Very little heat rise. I think the heat is completely off.
Blending dampers have been checked. No issues there. Floor, pane, defrost, all working fine and closing when on other settings.
This is an old fashioned manual system for those that weren't aware. Nothing that I can calibrate as far as climate control settings go.
Not necessarily. It would just be less cold as there is still cold air coming thorough the evaporator.
At any rate I looked up your Escape and didn't see one listed, so you're probably safe there. If you're having problems on a car, don't assume there isn't one- I've seen them on vehicles as new as 2005 that I can recall.
Originally Posted By: edwardh1
be sure you HEATER valve cuts off the hot water to the heater core
Wouldn't this cause vent air to be warm? When I run the vent, i get similar temps to outside air. Very little heat rise. I think the heat is completely off.
Blending dampers have been checked. No issues there. Floor, pane, defrost, all working fine and closing when on other settings.
This is an old fashioned manual system for those that weren't aware. Nothing that I can calibrate as far as climate control settings go.
Not necessarily. It would just be less cold as there is still cold air coming thorough the evaporator.
At any rate I looked up your Escape and didn't see one listed, so you're probably safe there. If you're having problems on a car, don't assume there isn't one- I've seen them on vehicles as new as 2005 that I can recall.
Originally Posted By: badtlc
Taking temps measurements on recirc doesn't provide you any useful data. The coils are designed to provide a specific delta-T which is the difference between outside temp and supply air. to get that measurement, you have to be running outside air across the coils and recirc setting doesn't do that.
OK, that's a fair point.
I'm currently unable to re-test with recirc OFF as the ECC is currently Tango Uniform.
Taking temps measurements on recirc doesn't provide you any useful data. The coils are designed to provide a specific delta-T which is the difference between outside temp and supply air. to get that measurement, you have to be running outside air across the coils and recirc setting doesn't do that.
OK, that's a fair point.
I'm currently unable to re-test with recirc OFF as the ECC is currently Tango Uniform.
I read this and had to read it again. So this AC system provides you with about a 30 degree temp drop from outside ambient air. So a 80 degree outside temp will give you about 50 degree air inside the truck? First off that isn't good enough. I'd like to see low 40's on a day like that. Also are you running it on recirculate? I have found that most cars REC mode is good for at-least a 10 degree decrease in vent temps(best decrease I've seen in this mode was a 17 degree decrease). If you want the best cooling REC is your friend. But
I'd like to know what the pressures are? If they are normal. I'd suspect a damaged door seal or I have seen a improperly sealed EVAP core after replacement. It allows air to bypass the evap core and leads to a increase in air temps.
I'd like to know what the pressures are? If they are normal. I'd suspect a damaged door seal or I have seen a improperly sealed EVAP core after replacement. It allows air to bypass the evap core and leads to a increase in air temps.
well I just got back from verifying temps. It is 89F outside and using outside air and fan on setting 3 (of 4) I was getting 59F from a temperature probe stuck about 5" into the supply vent closest to the evap coil. It was almost exactly 30F delta.
The escape had been parked in the garage and the test was done on highway at 60 MPH. THere should have been zero heat soak impact.
I don't have the ability to measure pressures or I would. I'm guessing I'll just have to take it to the dealer.
The escape had been parked in the garage and the test was done on highway at 60 MPH. THere should have been zero heat soak impact.
I don't have the ability to measure pressures or I would. I'm guessing I'll just have to take it to the dealer.
What do you get for air temp readings at idle? Based on your highway readings which is ideal for temps. The temp must be considerably higher? Does the recirculate/Max function lower the temps? Because it should.
Originally Posted By: Ojustracing
What do you get for air temp readings at idle? Based on your highway readings which is ideal for temps. The temp must be considerably higher? Does the recirculate/Max function lower the temps? Because it should.
At idle temps would shoot up but ididn't see how high it would go. Yes, recirculation lowered temps by around 10f in 5 to 10 minutes.
What do you get for air temp readings at idle? Based on your highway readings which is ideal for temps. The temp must be considerably higher? Does the recirculate/Max function lower the temps? Because it should.
At idle temps would shoot up but ididn't see how high it would go. Yes, recirculation lowered temps by around 10f in 5 to 10 minutes.
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