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Honda Thermal Limit Switch
Posted: Sat Jun 18, 2022 5:21 am
by Dgreen
Has anyone had any experience with these? I’m working on an 07 CR-V with intermittent AC. System works real good when the clutch engages. Clutch gap looks good. Pressures were 225 and 45 yesterday. It was a hot and humid day. I thought the compressor relay was bad. Changed it and it worked for a while and then started acting up again. Checked the area where the switch is mounted in the compressor and it showed to be 160 degrees. I looked for the part on ackits.com and didn’t see it.
Re: Honda Thermal Limit Switch
Posted: Sat Jun 18, 2022 6:57 am
by Cusser
Dgreen wrote: ↑Sat Jun 18, 2022 5:21 am
07 CR-V with intermittent AC. System works real good when the clutch engages. Clutch gap looks good. Pressures were 225 and 45 yesterday.
Did you actually measure the AC clutch gap or just eyeball it ??? I ask because in 2019 my AC clutch was slipping sometimes on my 1998 Frontier.
There were two shim washers under the drive plate, so I removed the thinner of the two, then re-installed the AC clutch drive plate and that will make the AC clutch "gap" narrower (yet not so narrow that it scrapes in the disengaged position). Fine 3 years later.
Re: Honda Thermal Limit Switch
Posted: Sat Jun 18, 2022 7:02 am
by tbirdtbird
Right on. Use feeler gauges, should be about .020
Re: Honda Thermal Limit Switch
Posted: Sat Jun 18, 2022 9:12 am
by Dgreen
I just looked at the clutch gap.
I found a mechanic on YouTube. He said Honda AC systems were prone to the thermal switch failing. I haven’t been able to locate the part. Looking like we may have to change the compressor. I will check the clutch gap with a feeler gauge before I do though.
Re: Honda Thermal Limit Switch
Posted: Sun Jun 19, 2022 11:04 am
by JohnHere
Dgreen wrote: ↑Sat Jun 18, 2022 5:21 am
Pressures were 225 and 45 yesterday. It was a hot and humid day.
How hot a day was it? What was the ambient temperature in front of the grille? The reason I ask is that the low-side pressure seems a bit elevated for adequate cooling. What was the center-vent temperature while it was cooling good?
Re: Honda Thermal Limit Switch
Posted: Mon Jun 20, 2022 5:59 am
by Dgreen
Vent temp was 45. I didn’t check temp at the condenser. Both radiator fans were running. Outside temp was 91.
Re: Honda Thermal Limit Switch
Posted: Mon Jun 20, 2022 10:14 am
by JohnHere
I don't think you mentioned this previously, but are you sure that the system is charged to the correct amount? This is a small-capacity system refrigerant-wise. So even an ounce or two low due to normal seasonal losses or a slow leak will negatively affect system operation.
Here are the specs that I have for your 2007 CR-V: 18.0 ounces net weight of R-134a and 4.5 ounces of PAG-46.
Re: Honda Thermal Limit Switch
Posted: Tue Jun 21, 2022 4:39 am
by Dgreen
Thanks for the specs.
It isn’t acting like it’s low. Works good when it works, but when it quits, it might not work all day.
Re: Honda Thermal Limit Switch
Posted: Tue Jun 21, 2022 6:51 am
by tbirdtbird
Diagnostics trumps guessing.
Write back when you have measured the gap
Re: Honda Thermal Limit Switch
Posted: Tue Jun 21, 2022 7:46 am
by JohnHere
If the system is borderline low on refrigerant, the PCM might be seeing varying pressures, which change with the ambient temperature, just enough to shut down the compressor occasionally.