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anemic heater - normal?

5631 Views 9 Replies 5 Participants Last post by  solson1041
I'll start by saying I always have very cold feet in the winter, and there's a cold concrete floor under my desk at work, so I'm in the habit of blasting hot air on my feet to warm them up in the car on the way home.

When I got my 2014 CT a few months ago in the spring I found that the heater didn't work at all -- it blew cold air. It was a chilly 5 hour drive home from the dealership. I brought it to my local later that week and they found a code that indicated a connector in the dash was disconnected. When they fixed that the heater started working.

Fast forward to this month when it's getting pretty wintery in Chicago (~20F). I'm finding that the heater never really heats up my toes like my old Civic did. The car warms up to a comfortable level but I don't reach a point where I have to turn the heat down. Even towards the end of my 30 minute commute, if I put the temp to 'max' and put my hand in the foot well, the air coming out feels warm but not hot.

Is this normal behavior for a CT? If it felt this way on a traditional car I'd be suspecting the thermostat was sticking partially open, but I know the hybrid has more complex heating systems. I wonder if a stop & go 30 minute city commute is never allowing the engine to get up to a temp that would properly cook my feet?
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I had the same problem this morning. Did you get it fixed? do you remember what was the problem?
So, for a few weeks I have been worried about this same problem, I live in Milwaukee and this is my first Winter with the car. I didn't realize the heater had an issue until the weather recently started getting cold. I have the same problem, and here's what I've learned.

1. Make sure there's no air in your coolant system. If you hear bubbles/rushing water sound under your dash when the engine first comes on, you probably have bubbles in your system, good news! This is an easy fix.

2. I took my car to a local mechanic for a proper flush of the coolant. They backflushed the heater core as well, so I know it's clean, and I don't have any air bubbles. My heater is very weak still though. It gets decently hot once the coolant reaches ~190 or so. Full operating temp. If the coolant temp is below 150, there's supposed to be a supplementary electric heater that kicks on. I suspect mine isn't working, but idk for sure. Judging by the diagrams, the heater core/electric heater are as inside the dash as it gets.

3. The flow of air out of the vents is way higher when the climate control is set to "Lo" or 60. When I raise the climate control to "Hi" or 85, airflow goes down considerably. The blower motor doesn't slow down at all, airflow only goes down. This makes me think there's something blocking the air at the heater core. Does this make sense to anyone else?

If anyone has any clues, I'd love to hear about it.
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So, for anyone searching this in the future. Make sure your car isn't on "Eco" mode. I just read this snippet from the service manual (I bought it from eManual Online, it's hard to follow, but solid.) I don't know if this will solve my problems, but it's a damn good start.

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