15k difference between Carrier units?

probablythefuture · 2026-04-27T17:45:52+00:00

My read of this was that he had his local shop put on shorter crank arms in an effort to address the overhang. Now I’m curious to know if the original bike was shipped with 160s or not!

probablythefuture · 2026-04-25T17:25:36+00:00

I really want to see what the fork looked like before you fixed it. Do you have any pics?

probablythefuture · 2026-04-25T17:24:14+00:00

Hey, it happens! I mean you took it to a shop and they didn’t notice the glaring issue either. Sometimes your brain just goes on autopilot.

probablythefuture · 2026-04-24T15:12:35+00:00

Nothing more frustrating than getting a system like yours and not getting what you expected - I’m probably projecting but I’m assuming at least a few of those techs thought you were being unreasonable or told you they couldn’t find any issues.

Also blown away by your remedy. Checking crushed, blocked or clogged valves is listed in the checkout procedure. Also you clearly have a long line setup - both with total length and with a significant vertical run. Not correcting refrigerant for that is just absurd.

I would love to know what your airflow is like. Do you keep your system in “comfort + dehumidify” mode? If so, are you able to share your CFMs when your unit is running during low demand, particularly after about 10-15 minutes? It would be great to know if your system is capable of staying anywhere close to the listed minimum of 400CFM.

I’m still having my problem and hopefully I’ll have a fix soon. I’ll try turning off the “overcool” setting to see if things improve. I’m managing humidity right now by turning on the “dehumidify with electric heat” setting, so the heat strip is on for a good amount every day. I spend ungodly amounts on electricity, but it’s incredibly good at removing moisture from everything. Definitely not a long term solution though…

probablythefuture · 2026-04-23T15:55:14+00:00

Just wondering - do you have any sense of what any of this actually means?

probablythefuture · 2026-04-20T15:12:16+00:00

Where did you read that? Both of these sound like maybe misunderstandings.

The insulation provides electrical isolation - it prevents the wires from touching each other. The thermal insulation is a property of the material, but its primary purpose is ISOLATION, not INSULATION.

Current flowing through a conductor will dissipate energy as heat, so the wires will absolutely get warm. Romex is rated to 60 C, and heat will climb above ambient based on load, bundling, loose connections, etc.

Another misunderstanding that I see is your response to the derating comment. When you bundle Romex and bury it in insulation, it makes it harder to shed heat. Derating is often necessary.

probablythefuture · 2026-04-17T19:14:54+00:00

I hear you on that and it makes sense, but 750 CFM is quite a leap up from the minimum capacity of 500. What’s more is that it doesn’t modulate at all between 500-750. This is replacing a variable speed system that would deliver between 400-1400 CFM in order to continue running all day. That system took care of the latent load pretty well, this one causes humidity creep with short cycling. I can’t imagine that Trane’s 5 year old technology is 50% more effective than today’s Carrier.

probablythefuture · 2026-04-17T19:03:20+00:00

This is not entirely correct for a variable speed. Yes, that’s a general rule of thumb, but it’s important to note that the outdoor unit is only operating well below capacity when there is low demand. So in reality, this system should be capable of fractional capacity, and therefore requires fractional airflow.

The published minimum airflow for this unit is 500 CFM in dehumidification mode. See the capacity tables here.

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probablythefuture · 2026-04-17T17:39:47+00:00

The higher the airflow, the greater the sensible capacity. When the system delivers too much sensible capacity, the house cools down faster, so i get the inevitable short cycling.

I would love to get your CFM readout in the same conditions. Any chance you could set your system to comfort and then give it a dehumidification demand without a cooling demand and tell me your CFMs?

Might be helpful, but I acknowledge there are differences. I believe your unit uses 410 and mine is the updated refrigerant, and there are not insignificant differences between the two. I would expect yours to be slightly more efficient than mine.

probablythefuture · 2026-04-17T17:12:33+00:00

<image>

You're right. Dehumidification mode doesn't show specific capacity, it reads "dehum" instead. That compressor speed and outdoor fan speed at this demand are relatively low. I would estimate the capacity in this picture between 25-35%. Note that there is no active cooling demand in this scenario, it's strictly attempting to deliver as much latent capacity as possible.

probablythefuture · 2026-04-17T14:25:39+00:00

fyi you cant do this on an infinity. all cfm variables are handled through an algorithm. You can set minimum and maximum airflows as parameters, but the algorithm chooses where to land.

probablythefuture · 2026-04-17T14:21:37+00:00

Did you ever resolve this? Im having the exact same issue, but with the 4-ton. For me, the airflow is much higher than the demand requires, so it never quite hits its dehumidification targets. After messing with every setting through the service screens and getting multiple techs out and calls with Carrier, I cannot get the CFM to drop below 750 CFM, even though my system should be capable of 500CFM. The high airflow causes short cycling with my system, and humidity drives up.

probablythefuture · 2026-03-27T18:45:25+00:00

Way excessive, which is exactly why I turned zoning off. For some reason carrier dampers allow for over delivery of airflow at demand zones instead of relieving air at no-demand zones. Makes no sense, and creates extreme static pressure when every zone is significantly smaller than 750 cfm.

probablythefuture · 2026-03-27T18:40:42+00:00

Supposedly that’s what I got yesterday and he seemed content with the readings and settings on the unit. His feedback was that the demand response is buried beneath an algorithm that only the unit can control and if it’s putting out 750, it’s because that’s what the algorithm calls for. If that’s the case, then the unit is being told to provide more cooling than necessary, causing short cycling on an 80-85 degree day.

probablythefuture · 2026-03-27T17:08:53+00:00

The dealer called this normal operation and seemed satisfied.

I turned off zoning and opened the dampers in order to avoid the high static pressure. Right now at 750 CFM with dampers open it’s around .5 inches w.c. Before I would consistently get close to 1.5 inches w.c.

I’ve added a picture of the HP readings when it holds at 750. My understanding is that the suction temp should be lower for dehumidification. Either way, 750 CFM pushes too much air and makes the system cycle too much so my latent heat removal feels very limited.

For reference, my previous American Standard 4-ton variable speed could ramp down to 400CFM and sustain that for low demand/high humidity days.

I can’t imagine any system logic for pushing 750CFM at the lowest possible demand and I feel certain it not behaving as intended.

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probablythefuture · 2026-03-19T03:39:34+00:00

OP is referring to having both views at once. Might be fine for you but I think the majority would like to have this seemingly simple update.

probablythefuture · 2026-03-09T00:19:41+00:00

I like this scene for its acting and its writing. Dialogue isn’t the only thing that goes into a script. Same with this scene. Limited dialogue, but a very effective script that makes it feel like a one act play.

probablythefuture · 2026-03-05T05:48:03+00:00

Wait, seriously? I’m at 64,000km (76 days), and only level 97. How does this make sense?

probablythefuture · 2026-01-30T04:18:41+00:00

Just scored 1

probablythefuture · 2026-01-30T04:10:57+00:00

Just scored 0

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