Poor A/C performance when car is hot inside

[brages]

Maybe this is like the guy with a leaky roof but it only leaks when it rains...

Anyway, car is a 2019 Honda Accord Hybrid. A/C had been working fine. Recently noticed the A/C struggling - but only in particular situations.

If the car has been sitting in the sun on a 90 degree or more day, and you start driving, the A/C is very weak. It's a little bit cool on the passenger's side but not at all on the driver's side. If you get out on the highway and start driving, eventually you get a little bit of coolness from the driver's side and after 15 minutes or so, it starts feeling pretty good.

In my typical use, I drive to work in the morning and A/C is fine. Park in a covered garage and drive home and again it feels fine. Even stopped in traffic, it's good enough to keep up in 90+ weather.

I haven't done any diagnostics and probably won't for a while, besides looking to see that the condenser/radiator fan - there is only one - seems to be running. There is an extended warranty (10 year, unlimited miles - yay!) on the condenser due to leakage from corrosion, and I'm going to take it to Honda and hope that's the problem. My appointment isn't for a couple more weeks.

The cool air on the passenger side and warm on the driver's side is something my Odyssey did when it was low on refrigerant. I guess there's enough liquid coolant hitting the evaporator to chill down the right side, but it's all vapor by the time it gets across to the left side. But the odd thing to me is that the A/C works pretty well most of the time.

This is a r1234yf system. I ordered some adapters and dye for it, but I think I'm just going to let Honda take care of it (hopefully under warranty).

 

[supton]

Single zone or two?

I wonder if it's just really heat soaked. Taking a while to transfer enough heat out. I realize though that it didn't seem to do this in the past... but I wonder if it's worst case scenario.

Recirculate is on, right? wondering if was on in the past but somehow isn't now. Or that maybe the door is blocked, or some thing that isn't due to low refrigerant, or dirt in the condenser, etc.

Edit: do you have a meat thermometer? I used to leave one in the dash and verify <40F air coming out. My VW wagon could blow 38F air yet that car never felt particularly cool.

 

[nwjones18]

I've had lots of blend door motor issues on my 08 CRV. Does yours change when you go to Hot?

 

[dogememe]

Aren’t these vehicles part of Honda extended warranty on AC issues? Swear I’ve read about that here recently from another user.

I would not suggest messing with the system at all first. I’d take it to the dealer and pay their $200 diag fee. If it’s under warranty you will not have to pay anything.

 

[FZ1]

Maybe this is like the guy with a leaky roof but it only leaks when it rains...

Anyway, car is a 2019 Honda Accord Hybrid. A/C had been working fine. Recently noticed the A/C struggling - but only in particular situations.

If the car has been sitting in the sun on a 90 degree or more day, and you start driving, the A/C is very weak. It's a little bit cool on the passenger's side but not at all on the driver's side. If you get out on the highway and start driving, eventually you get a little bit of coolness from the driver's side and after 15 minutes or so, it starts feeling pretty good.

In my typical use, I drive to work in the morning and A/C is fine. Park in a covered garage and drive home and again it feels fine. Even stopped in traffic, it's good enough to keep up in 90+ weather.

I haven't done any diagnostics and probably won't for a while, besides looking to see that the condenser/radiator fan - there is only one - seems to be running. There is an extended warranty (10 year, unlimited miles - yay!) on the condenser due to leakage from corrosion, and I'm going to take it to Honda and hope that's the problem. My appointment isn't for a couple more weeks.

The cool air on the passenger side and warm on the driver's side is something my Odyssey did when it was low on refrigerant. I guess there's enough liquid coolant hitting the evaporator to chill down the right side, but it's all vapor by the time it gets across to the left side. But the odd thing to me is that the A/C works pretty well most of the time.

This is a r1234yf system. I ordered some adapters and dye for it, but I think I'm just going to let Honda take care of it (hopefully under warranty).

Reduce the heat inside the car when parked. Get a Heat Shield for the Windshield and crack the rear windows 1/2 inch when you are parked. Cheap possible fix and makes your dashboard last longer.

 

[I<3oil]

Maybe this is like the guy with a leaky roof but it only leaks when it rains...

Anyway, car is a 2019 Honda Accord Hybrid. A/C had been working fine. Recently noticed the A/C struggling - but only in particular situations.

If the car has been sitting in the sun on a 90 degree or more day, and you start driving, the A/C is very weak. It's a little bit cool on the passenger's side but not at all on the driver's side. If you get out on the highway and start driving, eventually you get a little bit of coolness from the driver's side and after 15 minutes or so, it starts feeling pretty good.

In my typical use, I drive to work in the morning and A/C is fine. Park in a covered garage and drive home and again it feels fine. Even stopped in traffic, it's good enough to keep up in 90+ weather.

I haven't done any diagnostics and probably won't for a while, besides looking to see that the condenser/radiator fan - there is only one - seems to be running. There is an extended warranty (10 year, unlimited miles - yay!) on the condenser due to leakage from corrosion, and I'm going to take it to Honda and hope that's the problem. My appointment isn't for a couple more weeks.

The cool air on the passenger side and warm on the driver's side is something my Odyssey did when it was low on refrigerant. I guess there's enough liquid coolant hitting the evaporator to chill down the right side, but it's all vapor by the time it gets across to the left side. But the odd thing to me is that the A/C works pretty well most of the time.

This is a r1234yf system. I ordered some adapters and dye for it, but I think I'm just going to let Honda take care of it (hopefully under warranty).

Most likely condenser. We had the compressor shaft recall done and then the next summer, it wasn't cooling like it should, like before. Took it back in and condenser was leaking, fixed under extended warranty.

 

[brages]

Most likely condenser. We had the compressor shaft recall done and then the next summer, it wasn't cooling like it should, like before. Took it back in and condenser was leaking, fixed under extended warranty.

I'm expecting (hoping) it's the condenser. Interestingly, the hybrid compressor is electric and doesn't have an external shaft.

 

[Nukeman7]

I'm expecting (hoping) it's the condenser. Interestingly, the hybrid compressor is electric and doesn't have an external shaft.

You should be covered until 2029 per this TSB:

HONDA TSB 21-015

 

[GSCJR]

I suspect low refrigerant. Also, turn rec off when you get in, outside temperature is often not as hot as the vehicle interior when parked in the sun, and therefore harder (slower) to cool.

 

[KrisZ]

It's likely low on refrigerant. If this was a blend door issue, the driver side would never blow cold air.
I would not waste time finding a leak, unless this performance loss is sudden, like it worked fine a month or two ago under similar temps, and now it's not. I guess adding a dye would not hurt, but this sounds like a normal refrigerant loss that happens over the years. And I believe the r1234yf systems are even more prone to leaks, but not sure how factual is that. At least it seems a lot more new vehicles with r1234yf seem to suffer premature performance loss.

 

[The Critic]

Most likely condenser. We had the compressor shaft recall done and then the next summer, it wasn't cooling like it should, like before. Took it back in and condenser was leaking, fixed under extended warranty.

The evaporators leak just as often, and those are not covered under the warranty extension.

 

[I<3oil]

The evaporators leak just as often, and those are not covered under the warranty extension.

Ew, that sucks. Mine was covered under vehicle extended warranty (CR-V).

 

[MaximumMini]

The evaporators leak just as often, and those are not covered under the warranty extension.

Number one clue your evaporator is leaking or going to leak......

A putrid odor when you first turn on the AC. That's organic debris rotting in the Evap housing. Once you start smelling a foul odor when you first turn the AC on you're either already having a leak or getting close to it because that organic rot produces acid and that acid dissolves the aluminum.

 

[CleanSump]

Recirculate on? Also, on MAX it will also recirculate inside air.

 

[danstraylee]

When was the last time you changed the desiccant element? Only reason I ask is because not replacing it every few years (especially in Asian vehicles) will contribute to leaks in the system due to moisture accumulation.

 

[dbias]

Are you rolling down the windows to dump the 120+ interior air out of the vehicle for the first few blocks of driving?
I actually picked up this habit due to owning a couple Hondas as I’ve always felt their AC was a weak spot.

 

[K-Man]

Agreed with the heat-sink possibility.

You could have a blend-door problem developing because of dust in the system. An old trick is to use a leaf blower to push air into the vent openings on the dashboard, just a few seconds at each vent.

You could also have the beginning of a leak. Had to replace both Schrader valves in the A/C in my 2011 Ranger last year because they were leaking. Apparently this is common. The shop found no other leaks, and the A/C works well. Typically it takes a minute or so to start feeling cool air when the truck has been parked in the sun on a hot day, but that's because of all the heat trapped in the plenum and cab.

 

[379KITTY]

Another vote for low refrigerant. My Mother had a 98 Buick Century that sat for 3-4 years. Developed a small leak at compressor shaft seal. Prior to replacing, it would require almost a can of 134a every year or so. First sign was cold on passenger side only.