Constantly Running Converter fan question

trimacontrimacon Member Posts: 4
New to me 2018 T@B 320 S, Outback.  Parked in yard.  Loading and modifying it for our maiden voyage over Memorial Day weekend.  Battery at rest, coach switch in off position, reads 12.9V.  With switch in on position, plugged into shore power, reads 13.7V indicating converter is charging the battery.  That said, all sounds swell, but the converter fan is constantly on.  As I'm in/out of the coach loading and doing things, I notice the loud fan is a constant.  I can't imagine sleeping with it constantly running just below our heads.  It appears the converter is working otherwise well sending a charge to the battery, but does the fan need to constantly run regardless of the ambient temperature?  

Comments

  • Denny16Denny16 Member Posts: 5,431
    edited May 2021
    Are you referring to the Waco converter?  The fan will run, based on converter power load and temperature.  The charging circuit will kick the fan on whilst it is charging the battery.  Once charged, the fan should stop running.  

    An inverter is a separate device to turn 12VDC into 120VAC to run small appliances, if you have one it will have its own on/off switch, and should be switched off when not in use, as it will drain the battery quickly.  It also has a fan, which runs based on load and temperature.
    cheers
    2018 TaB400 Custom Boondock,  Jeep Gladiator truck, Northern California Coast.
  • trimacontrimacon Member Posts: 4
    sorry, yes converter.  fan won't stop, well it will if I unplug shore power. 
  • DalehelmanDalehelman Member Posts: 2,410
    Check to see if you have some sort of 12 volt draw on the system. That will cause the fan to come on.
    1. Hash  T@B Fun
  • Denny16Denny16 Member Posts: 5,431
    edited May 2021
    The fan is running because the battery is charging, as it has a 12.9VDC rested reading for an AGM, it is still charging until it gets to around 13VDC.  Once the battery comes up to full charge, the fan should stop running, if no other loads are present.  Is your fridge on also? It will add a load to the converter also. 
     Give it a few hours...
    cheers
    2018 TaB400 Custom Boondock,  Jeep Gladiator truck, Northern California Coast.
  • ScottGScottG Administrator Posts: 5,557
    Even when charging from a moderately depleted sate, my converter fan only runs for a few seconds when the battery is first connected. I've heard it come on briefly at other times, presumably when there was a heavy 12V load. 
    2015 T@B S

  • trimacontrimacon Member Posts: 4
    Denny16 said:
    The fan is running because the battery is charging, as it has a 12.9VDC rested reading.  Once the battery comes up to full,charge, the fan should stop running.  Give it a few hours...
    cheers
    at what voltage is the battery considered full, 13.7? I thought 12.9v was full.  its been on shore power for a week already other than intermittent lapses for road tests and genset tests.  
  • Sharon_is_SAMSharon_is_SAM Administrator Posts: 9,760
    edited May 2021
    @trimacon - The 320 batteries are supplied by the dealer and are generally regular lead acid.  You will see different charts.  AGM batteries are fully charged at 13.0 +.


    Sharon / 2017 T@B CSS / 2015 Toyota Sienna Minivan / Westlake, Ohio
  • ScottGScottG Administrator Posts: 5,557
    If we are talking about a regular wet cell lead acid battery, and it is truly "rested" (i.e., been off the charger for several hours), then 12.9V is about as fully charged as you are going to see.
    2015 T@B S

  • Denny16Denny16 Member Posts: 5,431
    Thanks, clarified my post.  ThenOP’s fridge if running would also produce a load on the converter?
    cheers
    2018 TaB400 Custom Boondock,  Jeep Gladiator truck, Northern California Coast.
  • ScottGScottG Administrator Posts: 5,557
    Denny16 said:
    Thanks, clarified my post.  ThenOP’s fridge if running would also produce a load on the converter?
    cheers
    I think the 2018 T@B S-models had a 3-way fridge. The 3-way shouldn't be operated on 12V unless connected to a running vehicle. I don't know for certain, but if the camper were plugged in and the fridge was running on 12V I wouldn't be surprised if that was enough of a load on the converter to keep the fan running. 
    2015 T@B S

  • Denny16Denny16 Member Posts: 5,431
    Yes, that was my thought too.  The three way has a fairly large power load whilst on DC operation mode.
    cheers
    2018 TaB400 Custom Boondock,  Jeep Gladiator truck, Northern California Coast.
  • pthomas745pthomas745 Moderator Posts: 3,989
    What test can be used on a converter to discover if it is failing or not working properly?  Always blaming the battery for this situation doesn't seem to solve the issue.  If you have a perfectly charged battery, and nothing in the trailer using 12V power, is it possible to test the WFCO for failure?  Or just replace and hope?
    2017 Outback
    Towed by 2014 Touareg TDi
  • Sharon_is_SAMSharon_is_SAM Administrator Posts: 9,760
    I found this in my notes from one of our members (?MuttonChops?)

    WFCO Fan is current controlled.  It should not be running all the time.

    If it is you have every possible DC load turned on or some type of a problem.
    Turn Off all DC loads except the Battery, still running ?
    Yes - - disconnect battery, still running ?
    No  - - check battery, water level, state of charge.
    Yes - - Remove DC fuses one by one.  Does fan stop?
    Yes - - That circuit has a current draw issue that is not blowing the fuse.

    Also, check to see that the WFCO Fan vents are clear.  Dog hair for example is a known issue for reducing/stopping the fan from cooling correctly.

    Sharon / 2017 T@B CSS / 2015 Toyota Sienna Minivan / Westlake, Ohio
Sign In or Register to comment.