Electrocooler compressor connected directly?

[RAA68]

Hoping to tap into the collective wisdom here.

Can’t find a clear answer in previous posts but is anyone running the electrocooler compressor without the Albright isolation contactor? Mine worked for about a year before it started shutting down the compressor when hot after 15-20 min of operation. When I took it apart one contact was burnt. Not sure if it was just bad luck or the contactor cannot handle the load and eventually fails.

For now, I have it connected directly to the battery but am concerned about parasitic drain. The classsic retrofit installation manual suggests that it can be bypassed and in fact that was the recommendation for earlier kits.

Is anyone else running it that way? Have you had issues with your battery? Have you had issues with the Albright SW60-360P contactor?

[Jonny H]

It has nothing to do with the compressor load. The contactor is not used to switch active power, only to isolate the 12V supply. It is only ever switched when the compressor is OFF.

The contacts wear because of the large inrush current caused by a large bank of capacitors inside the compressor. This happens when the power is first connected (compressor OFF). Unfortunately, if you have direct connection to the battery, the same capacitors will drain your battery in about 2 weeks. If you keep your car on a battery tender then this is ok.

Handling large inrush currents (>300A!) and fairly high sustained running currents (80A) is hard on a mechanical relay. The Albright unit is the best we can find at this time. I think you have been a bit unlucky. The one in my car is still good after a couple of years.

[Tom_in_NH]

Is there a setting in the configuration that would cause his compressor to cycle on/off more frequently than "normal" ? More frequent cycling would cause accelerated contact wear.

[RAA68]

Thanks Jonny and Tom.

For a long time I had the settings suggested in the manual. I also had the 80A fuse. When I noticed that the compressor was shutting down after a while and not able to stay on for more than a few minutes, in addition to removing the contactor I also changed several settings to those recommended by Duc Hunter (CTG, CTS, CHI, KP and others) and replaced the fuse with a 100A one. I will say that the AC performs much better and doesn’t cycle,

Actually, who knows if excessive cycling caused the contactor to fail prematurely. I’ll test it for a few weeks without one and if all is good, I’ll install a new one.

[Jonny H]

No, repeat, it has NOTHING to do with running the compressor or any settings for that matter. The relay pitting occurs when the system is OFF at the point the power is connected.

I know that sounds weird. Please google ‘inrush current’ for devices with capacitor banks.

Having said that, if you increased the current demand by changing settings, that would likely amplify issues if the relay was already pitted but not the root cause of the pitting.