Adding a thermostat to a Xantrex Truecharg2 battery charger

[albert001]

Hello,

I have an Xantrex Truecharge2 battery charger with a case fan that AFAIK is constantly running. The Truecharg1 which I also own uses large heat sinks without a fan. Where the Truecharge2 a case fan was added. I'm told it is thermostat controlled and is suppose to only turn on when the case with PCB reaches a certain temperature.

That's what I've been told anyway and it makes sense that it's case fan would have it's own thermostat.

The problem is my Truecharge2 case fan seems to be on all the time. Everytime I've checked on the charger the fan is running. I've tested outdoors inside an engine compartment connected to a single starting battery, with outdoor Temps around 40 deg F, for several days while the Truecharge2 is in float mode. 

Charger is functioning and charging as it should but AFAIK it's case fan is constantly running. Which is probably no big deal as likely the only thing that would happen is the case fan would burn out prematurely. The Truecharge2 20 amp version is designed to be installed connected to up to three batteries 24/7.

After thinking this over I decided to disconnect the case fan from the PCB and run the case fan using my own thermostat module such as a W1209, W1209WK, W3230, W1401, etc. all which which come with a temperature probe and are  programmable, low and high temperature setpoints. AFAIK the load can be either AC or DC where  the thermostat module  powered by 12 VDC (there is also a 24 volt version) will power e.g. a 12 vdc fan. The thermostat, depending on which version, usually come with a 10 to 20 amp relay.

I picked a couple W1209's and a W3230 and looking at a W1401.

I'm still waiting for the thermostats to arrive. After some experimentation I think the temperature probe can be connected to the inside of the case or perhaps one of the five heatsinks soldered to the Truecharge2's pcb.

I'm looking for any feedback to determine if I'm overlooking anything. The Truecharge2 case fan  AFAIK is 12 VDC, and controlled by the PCB through a simple 4 pin connector which can be easily disconnected.

Other than for it's fan constantly running the Truecharge2 is a great charger, using PWM to create  charging rates. It has many controls for different charging rates and battery types.

I also purchased a temperature probe for the Truecharge2 so it's able to produce  more accurate charging rates.  There is also a remote panel where the configure the  Maximum Output Current Percentage. 

I also found a W1308 which has a 10 amp relay,  comes in different power versions with either one or two LED readouts.

https://www.ebay.com/itm/W1308-Dual-LED-Digital-12V-10A-Sensor-Temperature-Thermostat-Alarm-Controller/163356836806?hash=item2608d383c6:m:mAXY9nXmMWDmKLQ2G28Taqw:rk:18:pf:0

W3230 20 amp relay plus other  models:

https://www.ebay.com/itm/W1308-W1209-WK-W1301-W3230-DC-12V-Thermostat-Temperature-Control-Switch-Sensor/202375550254?ssPageName=STRK%3AMEBIDX%3AIT&var=502368278670&_trksid=p2057872.m2749.l2649

[albert001]

One problem I'm having is the information available is unclear  if any of the W series modules are capable of switching to Fahrenheit? I'm located in the US and rarely if ever  use Celsius to determine temperature.