Inverter fans always running

[Jeff Bayley]

I threw this in an existing thread but didn't get much play on it so posting it fresh here.

Regarding my Trace Inverters and power consuption at night while dry camping:

Can I avoid draw on my batteries by shutting the inverter (the one not running the fridge) down at night OR does it help to turn the 12 or 24 volt mains (in the engine bay) off at night ? I never do either of these. I can always here the inverters internal fans running when I walk by the battery bay where they are located. These Internal fans have to be making a draw. Are they ever supposed to shut off ? If there is a thermostat, maybe it's bad ??? Should they run even in mild 60 degree weather at night ?

Also, with the Inverters in with the lead acid batteries, are there fumes that are harming the inverters ?

On the 12 and 24 volt switches, are these supposed to be shut off when plugged in ? Do they make a draw if they are not or is it just a security measure to turn them off ?

[Jon Wehrenberg]

Jeff,

If your mission in life is dry camping I see large solar panels in your future.

I may be wrong, but I think our converters design our systems for occasional overnight stop overs without shore power, but for the most part we drive energy hogs designed to provide many creature comforts.

On our coach we have internal inverter fans, but to supplement them we have an external fan that we can control, that we tend to leave on continuously because we are either charging our batteries via shore or generator power, or our inverters are taking battery power to feed our TVs or refrigerator.

I think your available battery power has a greater influence on the hours of use you get, than whether you turn off an inverter or fan. I see attempting to conserve battery power at the expense of living large akin to shifting your Maybach into neutral going down hills to save gas. I would instead look for ways to add batteries.

Crank up the generator and run the hell out of it (it probably has 30,000 hours of life or more) or take that big fat power cord and plug into 50 amp service.

[Joe Camper]

Internal inverter fans never run when there is no a/c input from shore or generator. Only when there IS shore or gen power into the inverter and it is in charge mode does the cooling fan work and even then only intermittent because they also have a thermostatic switch.

Most converters added external cooling fans and the type quantity and design runs the entire gammit.

This is a good topic to reintroduce.

Many and most conversions use dc fans but some were ac lew pops marathon had an ac fan with a squirrel cage a Dayton product. Never saw another yet like his but they r out there.

The cool setups, pun intended, have inverters mounted at the bottom of the bay and 2 external converter installed dc cooling fans 1 suckling cold air in the bottom and the other blowing out the hot air at the top of the bay and both hooked thru a thermostatic switch .

All these fans and thermo switches r available at granger 12 and 24 volt. Fans r about 50 thermo switch is about 15.

If your bus is used u should replace these fans.

If u have a conversion without any converter installed additional air flow thru the bay u should absolutly add it.

If u do have all these goodies and feel comfortable everything is happy open up the bay door on a hot summer day and see just how hot it actually is.

I've seen I think it was a liberty, but don't hold me to that, that had a air conditioning vent cut into the ceiling of the bay. I didn't investigate if it was ducted from otr ac or a cruise air but regardless I thought that was a good idea. I have only seen that once and I was wondering how compromising the electrical bay to the cabin thru a vent would fair with the fire Marshall but what do I know.

Heat is probably your inverters worst nighmare. An open door on the hot summer days is certainly nothing to be ashamed of.

When replacing or upgrading another good feature is a control switch that gives u a manual opporation as well as the auto thermostaticly controlled mode.

Getting back to the internal fans for a minute.

Internal cooling fan failure is OFTEN a direct cause of inverter failures in general. I've had a couple sets of heart inverters that were bad and replaced that were given to me that I took apart and repaired that had fans that were not working, due to both burned to fan motors and bad thermo switches, and it's probably safe to assume something got too hot that otherwise would not have happened.

Inverter cooling fans should be tested on older buses unless u r observant have a good ear and know your bus as to verify their opp by hearing them when they kick in.

A hair dryer blowing into louvers on the case when charging should turn them on after a certain amount of time. If u have never heard your internal cooling fans and can't force them on by introducing hot air to test them THAT IS NO GOOD bus driver.

Comments? What have u got?

[dale farley]

Joe, This is a good thread to revisit. I need to check the fan/fans on my bus. I've got two 4000 watt inverters, and I don't recall that I've ever heard the fans running.

[Joe Camper]

Dale I know on the heart inverters where to point a hot air blow dryer in the right louvers as u r looking at it. Don't know where the sensor is on trace or magnum or outback. Regardless the blow dryer should still make them go. Also I wouldn't do it with a garage type heat gun stick to the lessor hair dryer to be safe. I'm sure some might think I can't even see my inverters.......well, can't help that it's an important piece of the puzzle none the less.

Also I'm assuming outback and magnum internal cooling fans r set up the same IE fans only go on charge mode and r temp controled. That needs to be clarified if someone please could? Up to now I have no experience with those.

[Gil_J]

Joe,

While in inverter mode, inverter/chargers can still get toasty. I'm not sure why the internal fan only runs in charger mode. Here's what the Trace SW model manual states:

"As an inverter, overheating can be caused by attempting to operate too large of a load for too long, a failure of the inverter cooling fans, or that the air flow into or out of the inverter is blocked."

Most, if not all, inverter/chargers used by converters will raise an alarm if they get too hot. If the fan is inoperative an overheat alarm will likely be experienced.