@Trader4 – who needs thermal fuse behind compressor clutch? Just kidding
Now with all seriousness:
With over 35 years, experience working with cars and electrical / electronic equipment I (I am not forcing my opinion on everyone here) felt that bypassing thermal fuse in this particular situation is acceptable risk. Here are my points:
1. I did not see thermal fuses in the AC clutches until 21st century (Possibly it just me).
2. I did not research this, but my best guess for why it is there – avoiding clutch seizure after prolonged slippage. In this case scenario, AC belt will disintegrate and potentially damage other components. Giving this potential unpleasant scenario – thermal fuse seems like a cheap insurance policy.
3. In reality, AC clutch may slip as of result of excessive wear, excessive system pressure due to improperly charged system or overheat due to inadequate ventilation (bad Auxiliary fan, etc.) and clutch bearing or compressor seizure which is rarely happens without warning sounds
4. As most of us on this forum, I pay close attention and promptly investigate any abnormal sounds and perform maintenance as required.
5. My AC system performed top notch prior to failure and after careful inspection I believe clutch circuit became open not due to the excessive heat, but internal fuse failure due to age and exposure to the environment it located.
6. The fuse used here is about half the size of common thermal fuses available at local components store (see picture). Due to limited space and difficulty to solder new fuse in the same location, I decided to cut corner and just bypass it
7. My original intent was to find new or used replacement coil, but two years later I have little motivation to touch it again
Now for those whose clutch failed and who must fix it right:
Pics below – compressor type, original fuse and size comparison between original and commonly used in US applications thermal fuses.
eBay link for the one that I believe will work here. Please do your own research before buying. Be very careful if you decide to solder it in – melted solder applied to the leads will be hot enough to blow new fuse.
http://www.ebay.com/itm/5-Pcs-ELCUT-UMI-Microtemp-Thermal-Fuse-Axial-Type-127-TF-Cutoff-187-2A-250V-/181635002957?
pt=LH_DefaultDomain_0&hash=item2a4a4a324d