Definitely check the fluids of the two Trojan batteries... Just being charged with only 13V is not good for batteries that like to see the 14.8VDC when being charged...
The IOTA is good charger but needs to have the IQ controller to get the smart mode charging voltages when you charge your batteries. It will only go to 14.4VDC however and not the 14.8 recommended for the Trojan Batteries. Having 14.4VDC will be alot better than only having the 13.6VDC...
Also the batteries will boil out the fluids if it is left to a single mode 13.6VDC charging setup over time... Getting the smart mode different voltages going really helps in the situation...
Need to look over your home source of power you are using and try to find a receptacle that is powered by a circuit breaker with nothing on it but your trailer hookup... I lucked out in my garage of having a dedicated 120VAC 20AMP Circuit that was installed just for an air compressor setup which is not used anymore. It gives me a good steady 120VAC under control of a dedicated 20AMP Circuit breaker.
I am probably going to be presented with a similar 14.4VDC verses 14.8VDC situation here as I am in the planning stage of building up two groups of 6VDC batteries in series for my next battery bank. My Converter/charger is a PD9260C 60AMPS which runs the smart modes great but only goes as high as 14.4VDC... Really hadn't planned on changing it out and was thinking that my 14.4VDC 60AMP charging source would get the job done but just take alittle longer.... I too may have to go with the newer chargers on the market now that run the 14.8VDC voltages for the Trojan Batteries...
In your case with just a 13.6VDC single mode charging source the Industry say it will take 78 hours of constant charging to get the standard flooded cell deep cycle battery to a full 100 percent charge state.
This is what PROGRESSIVE Dynamics states in their operating manual on how long it takes to charge a battery using the DC VOLTAGEs listed below:
"Progressive Dynamics ran this test on the amount of time it took a PD9155 (55-amp) converter/charger set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.
14.4-VOLTS (Boost Mode) โ Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.
13.6-VOLTS (Normal Mode) โ Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.
13.2-VOLTS (Storage Mode) โ Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."
This is based on having 17-20AMPS DC current available for each battery in your battery bank... NOTE That Progressive Dynamics doesn't even list using DC Charge Voltages around the 12.0VC range as this would take alot more than 100 hours to achieve a 90% or 100% charge state.
Like said above in a couple of posts you are starving those Trojan Batteries to death and they may perhaps have already failed on you performance wise... This charts shows the setting State of Charge batteries...
Just using the multimeter to read the battery setting voltages is just a good feeling measurement. The best way is to use the Hydrometer Test for each cell to know for sure...
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
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