Hi everybody I’m new here hope you can help me I ave a motorhome Fleetwood soutwind 206 and my house battery won’t charge I tested tehe charger and it’s bad so the charger is a WFCO 9875 it’s a 75A so the thing I want to know can I put a 30A instead of the 75A
thank you for your answer
you can also switch brands and go to a Power dynamics charger, I don't know if I would step down the charge amperage though. what I would do is make sure what ever you buy has a good Li mode, not auto detect either. that way in the future if you decide to go to LiFePO4 batteries it is easy or if you sell it, it is a selling feature.
Agreed, WFCO are pretty well established to be junk.
Most of the newer units have a lithium mode, so it should be no cost to get one that can handle lithium or lead acid and when you replace the batteries, lithium makes a lot of sense. Lighter and for the same amp-hr rating, they have double the usable amp-hr because you can safely drag them very low. Lead-acid don't like to be below 50% charge.
75amp charger is overkill for almost all situations. It can also be a hassle if you are on a 30amp shore power pedestal. If it decides to max out, it's going to pull 1000-1100w. If the aircon is pulling 1500w, that doesn't leave a lot of room for other misc loads before you start popping breakers (30amp is 3600w peak but only 2800w continuous load).
Even if you have a massive 400amp-hr battery bank and it's dead, one overnight with a 35amp charger will have them full by morning. So unless you regularly drain the battery bank and want to fast charge with a generator, not rally any benefit to the big charger.
When our 55amp WFCO failed, we switched to a 35amp powermax and have been satisfied. Nothing 12v DC that runs for more than a few seconds pulls anything close to 35amp, so if you are running the stabilizers/slides, it pulls the excess amps off the batteries and within a few minutes, the charger has replaced it. For lighter continuous loads like the lights, I've never seen more than 10amps (usually 5-7).
and see I would keep the 75 amp capability if I could, just for that faster charging ability.
Yup, it will just take 60% longer to charge the batteries the same amount.
But unless you are boondocking and charging a big battery bank from near dead, does it matter?
If in a campground, for a single overnight, you typically will have 14-18hr of charging from the pedestal. 14hr at 30amp is 420amp-hr replaced.
Ok thank you I will try it
Try what?
