Starcool draining second battery

[georgesz]

Hello there! I hope I am not the first person in the forum to have this problem...

I have a 93 Sportsmobile (Ford E-250) that drains the secondary battery completely within less than two hours when we hook up to 110 volts. The rest of the stuff (refrigerator, lights, etc) can run for days without draining the secondary battery if I hook up to 110.

When I drive the van the Starcool blower has no negative effect on the second battery - in fact, even if I run the van on idle with the Starcool on Medium, the alternator still generates enough amperage to charge the second battery fully withing a couple of hours. Last weekend I ended up idling the van in the middle of the night for about two hours to run the AC and stay alive in the heat until the morning.

I am wondering if my 45 Amp converter is just too weak, or if the 12 volt AC blower under the refrigerator is hooked up wrong? The blower and AC works fine for about 1.5 to 2 hours and then when the blower speed gets low, the 110v compressor no longer kicks in.

Fortunately we replaced a defective battery isolator a while back, so our starting battery is not drained. However, no AC makes it hard to camp in South Texas in the summer! We tried camping in hot weather only twice since we have the Sportsmobile, and we are determined not to do it again until we fix this problem.

Thanks for any pointers!

George S

[John Kalmbach]

Hello George,

The 12VDC fans on the Starcool do use a lot of power (up to 35 amps). It sounds like your 45amp converter charger is not charging the house battery. Confirm that the GFCI outlet the charger plugs in to is not tripped (you should try to test and reset it while connected to shore power). Also confirm the AC circuit breaker protecting the outlet is not tripped. Using a voltmeter, check the voltage of the house battery when you're connected to shore power, it should be 13.2-14.2 volts (approximately).

It sounds like the Starcool 12VDC fans are all working fine since the system works okay while the engine is operating.

I hope this helps!

John K.

[georgesz]

Thanks for the reply John!

I checked the outgoing voltage on the converter and it was completely dead. Fortunately the second battery was still charged because I drive the van about once per week.

I bought a Progressive Dynamics Intellipower 9145 converter, and I tested the load going from the 110 plug to the converter when the AC blower is running, and it is pulling about 5.6 amps with the blower on High, 5.4 amps on medium, and 5.2 amps on low. The total amperage from the house AC aoutlet is about 17 Amps when the 110 compressor and DC blower are running.

I can easily tell the difference in the blower RPM when I turn off the converter, so the problem was the converter. I will test it soon overnight, but will also do an easy test by disconnecting the second battery to see if the blower works only off the converter.

Thanks again!