[guzvan]

Anyone have a clever way to power the rear blower fan with auxiliary power? Could it be as easy as adding a 12v circuit to the existing connector?

I'd like to use my house battery to circulate air at night. I don't need AC and don't want to turn the key on - plus that only works for 75 minutes.. Would be great to use the fan my van came with instead of installing another one.

If anyone knows the power consumption of this blower that would also be helpful. If this is too high I'll bail on the idea.

2020 BEMM:
At engine off, under SBG control, the BCM provides the following timers and SOC values
before disconnect. The timer resets each ignition on and in engine run.
– For a single battery and non-AGM, 30 minutes activation limit and 60% SOC limit
– For a twin AGM battery (in vehicle configuration) the timeout is 75 minutes and SOC limit is 40%

Many thanks 🙏

 

[asdrew]

lol, this came up in the approval queue while I was perusing other threads.

I approved it quickly because though it is not a need of ours I find the idea intriguing. It seems that if tying in the right spot you could pull this off. I'd investigate using a switched relay and possibly even a dimmer or stepped speed control.

 

[guzvan]

Thanks @asdrew - Glad I could spark some interest. I know it's a little strange. My goal is to crack some windows and keep the air moving. Ford did a pretty sweet job at designing that system so I might as well try to use it.

A relay and controller is a good place to start. Guess I'll grab a multimeter, I can't find wiring diagrams for the blower/rear climate control. If anyone has that send it

 

[ranxerox]

That fan pulls something like 40 amps. The 250 amp alternator is part of the Rear Air Package, So it takes a bigger alternator just to run it.
This idea has come up several times before and all of the details are in past forum threads.

 

[Mitch]

It's going to be an absolute ton of power to run and will give you the equivelant airflow of one of those little clip-on desk fans. Air doesn't like being squished through tiny windy vent passages!

 

[guzvan]

Thanks @Mitch & @ranxerox that saved me a lot of time.

I thought it might be a power hog.. too bad, the amount of air those vents move is plenty for me.

 

[Mobileempire]

I would guess it draws about 20 amps , way too much for a house battery.
I used to use a 5 inch square PC fan that drew about 44 milliamps , the trick was to aim it at my face.
You'd be surprised at how cool it will keep you , also no need to run a roof vent and use up electricity.
When it gets so hot and humid that the fan only blows warm air it's time to turn on the air conditioner.
That's why I removed my 12 volt roof fan and replaced it with a 110 volt roof fan.
The only time my 110volt roof fan is turned on is when the air conditioner is turned on , that way the roof fan doesn't draw the battery down because the air conditioner and 110 volt roof fan is powered by generator or shore power.
My pc fan quit working and so I replaced it with a $90 Sirocco fan , the Pc fan does just as good a job and is free , the only benefit of the Sirocco is its more adjustable to aim the air for different positions , laying down sitting , reclining.

 

[guzvan]

That sirocco is sweet and only .3 amps on the high setting!

 

[Van Gogh]

At some point I may be able to separate the wires enough to get my dc amp clamp meter around one and see what the rear fan actually draws on low setting without the compressor running. It may be much less than we think. But either way, it's probably not the ideal solution. I'm still trying to figure out where to fit a 42 seer minisplit and a 20kWh lithium bank. If I can pull it off, it'll mean many days of 9k btu a/c per charge (only draws about 215-250W at peak efficiency). Hopefully Nations comes through on its 250A and 275A 24V alternators and mounting hardware, which I'll couple with SEIC high idle recharging via low battery SOC triggered autostart (e.g. Viper or similar).

 

[going4speed]

Does the rear ac have it's own fuse? I cant imagine that fan pulling 20 amps. That's a ton of juice.

 

[ranxerox]

Does the rear ac have it's own fuse? I cant imagine that fan pulling 20 amps. That's a ton of juice.

Page 200 of my 2016 Owners Manual, Fuse F41, Rear Blower Motor, 40 Amps

http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2016-Transit-Owners-Manual-version-2_om_EN-US_12_2015.pdf

 

[Ajchien]

At some point I may be able to separate the wires enough to get my dc amp clamp meter around one and see what the rear fan actually draws on low setting without the compressor running. It may be much less than we think.

if you’re really that interested, something like this could make things much easier.it should come in various fuse sizes:ESI 307M Fuse Buddy Mini Current Loop Amazon.com: ESI 307M Fuse Buddy Mini Current Loop: Automotive

 

[Mobileempire]

At some point I may be able to separate the wires enough to get my dc amp clamp meter around one and see what the rear fan actually draws on low setting without the compressor running. It may be much less than we think. But either way, it's probably not the ideal solution. I'm still trying to figure out where to fit a 42 seer minisplit and a 20kWh lithium bank. If I can pull it off, it'll mean many days of 9k btu a/c per charge (only draws about 215-250W at peak efficiency). Hopefully Nations comes through on its 250A and 275A 24V alternators and mounting hardware, which I'll couple with SEIC high idle recharging via low battery SOC triggered autostart (e.g. Viper or similar).

How do you plan to charge the 20kwh battery bank back up?

 

[Van Gogh]

if you’re really that interested, something like this could make things much easier.it should come in various fuse sizes:ESI 307M Fuse Buddy Mini Current Loop Amazon.com: ESI 307M Fuse Buddy Mini Current Loop: Automotive

Nice. Thanks Ajchien. I ordered one, but then cancelled it because I got to thinking this might be really hard to fit into the tight area down there where the fuse box is. Have you used this with a transit and it fit no problem? I really like the idea of this. Such a nice addition to pair with the fluke.

 

[Van Gogh]

How do you plan to charge the 20kwh battery bank back up?

That was this part:

Hopefully Nations comes through on its 250A and 275A 24V alternators and mounting hardware, which I'll couple with SEIC high idle recharging via low battery SOC triggered autostart (e.g. Viper or similar).

In shore power situations I'll most likely have a sigineer 6kW split phase 120/240V inverter/charger or similar. Need 240 to run ultra high SEER a/c units. There's some loss in the step up conversion to 120/240, but it's max 12%, and with the extreme efficiency of these units, they'll draw such a small load that the inverter won't be anywhere near it's peak loss 12% range, probably more like 6% loss. With 42 SEER being orders of magnitude more efficient than 12 and 24V RV a/c units, suddenly 6% conversion loss starts to look like a rounding error, and I believe the best 120V minisplit I found was 30 SEER, so still about 40% less efficient. The sigineer has an 85A lithium charger. Slower, than the alternator for sure, but with shore you're not in a rush anyways since your loads are already powered, and you'd really like to leave your bank sitting at 40-50% SOC, and just top it off to 80-90% the day before you head off-grid.

The reality is Nations will have that setup available soon. It's a given. How well it performs is another story, especially in the hot desert southwest, but Adam makes a pretty compelling argument that his customer requirements are high enough that it'll at least deliver 5kW nonstop, which would be 4 hours of high idling for 20kW, but realistically no one charges their lithium bank to 100% and discharges to 0%, so it's more like 20kW x 0.8 = 16kW, which at 5kW charging is about 3 hours. The alternator can get up to ~7kW at peak, so sometimes it may even be as little as 2.3 hours when spring/fall temps aren't too bad. But I'm starting to lean towards the 250A instead of the 275A, so maybe 3 hours is the best estimate. The output curve on the 250A looks better at high temperatures, and it's less likely to burn up with heavy use. Certainly worth the 25A difference, especially when you consider the fact that most of the power demand will be during the hot summer months. No sense in frying a ~$1500 alternator for a measly 25A.

Cheers.

 

[Ajchien]

Nice. Thanks Ajchien. I ordered one, but then cancelled it because I got to thinking this might be really hard to fit into the tight area down there where the fuse box is. Have you used this with a transit and it fit no problem? I really like the idea of this. Such a nice addition to pare with the fluke.

Have not used it on a transit. That particular one I have for my Honda vehicles. It does get cramped in the under-dash fuse box.

let me show you these things. You’d have to buy more parts to get a fuse connected inline, but you could change the length of your loop needed, without having to “modify” the original tool. You should scroll down and look at how they Demonstrate wiring it up for various applications:

General Technologies Corp GTC063 GTC06X Fuse Socket Connector Kit, 1 Pack https://www.amazon.com/dp/B0787JKMTH/ref=cm_sw_r_cp_tai_HERxFbBYM00J9

 

[going4speed]

Fair enough but a fuse rating does not necessarily dictate circuit draw.

Page 200 of my 2016 Owners Manual, Fuse F41, Rear Blower Motor, 40 Amps

http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2016-Transit-Owners-Manual-version-2_om_EN-US_12_2015.pdf

 

[Van Gogh]

Have not used it on a transit. That particular one I have for my Honda vehicles. It does get cramped in the under-dash fuse box.

let me show you these things. You’d have to buy more parts to get a fuse connected inline, but you could change the length of your loop needed, without having to “modify” the original tool. You should scroll down and look at how they Demonstrate wiring it up for various applications:

General Technologies Corp GTC063 GTC06X Fuse Socket Connector Kit, 1 Pack Amazon.com: General Technologies Corp GTC063 GTC06X Fuse Socket Connector Kit, 1 Pack: Automotive

Awesome. I love the idea of being able to selectively power off circuits like that. Great way to build a few mad max style kill switches to prevent vehicle theft. Thanks!

 

[whitemage25]

I looked into this about a year ago and metered the amp draw of the fan with my clamp. I got 3.02A on 1, 9.96A on 2, 19.37A on 3, and 22.15A on high. I ended up going with the MaxxFan because on its highest setting it only draws 2.8A and it’s pulling in cooler outside air vs just recirculating.

 

[asdrew]

I looked into this about a year ago and metered the amp draw of the fan with my clamp. I got 3.02A on 1, 9.96A on 2, 19.37A on 3, and 22.15A on high. I ended up going with the MaxxFan because on its highest setting it only draws 2.8A and it’s pulling in cooler outside air vs just recirculating.

Great info, thx!