# Exhaust Fan output **URL:** \ **Category:** Sovol SV08\ **Created:** [September 18, 2026, 5:43pm UTC](https://forum.sovol3d.com/t/exhaust-fan-output/10383 "2026-09-18T17:43:07Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Riccardo\_Bramati](https://avatars.discourse-cdn.com/v4/letter/r/b19c9b/32.png) [@Riccardo\_Bramati](https://forum.sovol3d.com/u/Riccardo_Bramati)\ **Post date:** [September 18, 2026, 5:43pm UTC](https://forum.sovol3d.com/t/exhaust-fan-output/10383/1 "2026-09-18T17:43:07Z")
Hi everyone, I’m looking for some technical information about the Sovol SV08 mainboard, specifically the 24 V Exhaust Fan output controlled by MCU pin PA2 (fan3 in the stock Klipper configuration). Does anyone know the maximum continuous current rating of this fan output, or perhaps the part number of the MOSFET/driver used for PA2? The reason I’m asking is that I’m designing an external recirculating filtration system for my enclosed SV08. The idea is to reuse the original rear exhaust fan and add two 24 V 5015 blowers for an activated-carbon + HEPA filtration system. The original exhaust fan in my printer is: HXR EFC-09E24L – DC 24 V – 0.15 A The two additional 5015 blowers are approximately: 2 × 0.08 A = 0.16 A Therefore, in the worst case, if both systems were operated simultaneously, the PA2 fan output would see approximately: 0.15 A + 0.16 A = 0.31 A @ 24 V I’m considering using relays to select between: original exhaust fan only filtration blowers only possibly both simultaneously Before doing that, however, I’d like to know the actual safe current capability of the PA2-controlled 24 V fan output, rather than simply assuming that 310 mA is safe. If anyone has a schematic, high-resolution photo of the SV08 mainboard, MOSFET part number, or an official current specification for this output, that would be very helpful. Thanks! ---
**Author:** ![Lion](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.sovol3d.com/lion/32/5586_2.png) [@Lion](https://forum.sovol3d.com/u/Lion)\ **Post date:** [September 18, 2026, 5:49pm UTC](https://forum.sovol3d.com/t/exhaust-fan-output/10383/2 "2026-09-18T17:49:34Z")
There is a pic in this thread, don’t know if it will suit your needs or not. > [@SV08 64bit controller pin-out](https://forum.sovol3d.com/t/sv08-64bit-controller-pin-out/5333/8): > > I found the pin mapping with an OHM meter, GND and Vcc were measured to the main voltage terminals to the pins in question. Z,X,Y stops, Filament Detection and FAN/LED connectors NOTE: I just ordered a Bambu Labs printer, I’m spending more time working on: Creative K1 (dead end, no fix), Twotrees SK1 (New Main board, heat bed, Z axes tri-supports) and this Sovol SV08 (wiring issues, heated chamber with add-on MCU, upgraded Klipper with EMMC 32GB, case encloser with extensions, po… ---
**Author:** ![cardoc](https://avatars.discourse-cdn.com/v4/letter/c/ec9cab/32.png) [@cardoc](https://forum.sovol3d.com/u/cardoc)\ **Post date:** [September 18, 2026, 11:36pm UTC](https://forum.sovol3d.com/t/exhaust-fan-output/10383/3 "2026-09-18T23:36:44Z")
The MCU schematic shows PA2 is pin 25. You’ll have to do continuity tracing in your board. > **[H616\_JC\_6Z\_V1\_2\_MCU.pdf](https://github.com/Sovol3d/SV08/blob/main/Motherboard/H616_JC_6Z_V1_2_MCU.pdf)** OR just spend a dollar and remote mount a mofset and drive it with the 24v PWM output from the fan connector. ---
**Author:** ![Riccardo\_Bramati](https://avatars.discourse-cdn.com/v4/letter/r/b19c9b/32.png) [@Riccardo\_Bramati](https://forum.sovol3d.com/u/Riccardo_Bramati)\ **Post date:** [September 19, 2026, 8:37am UTC](https://forum.sovol3d.com/t/exhaust-fan-output/10383/4 "2026-09-19T08:37:14Z")
Tks a lot. I take a look inside PDF and I hope could be useful. About this “OR just spend a dollar and remote mount a mofset and drive it with the 24v PWM output from the fan connector.” I’ve already planning a little PCB to split voltage from 24V PWM for Fan and a double filtering system