Tech News

Delta PRO Firmware Review

Please read the deep dive review article about the DeltaPRO if you haven’t done yet HERE.

Want to know how the Delta PRO performed after more than 6 months of continuous use? Read the detailed article HERE.

Firmware .96 was released on the 6th of July 2022 with the following fixes:

  1. Optimized the problem whereby the actual DC charging current value exceeds the app limit value.
  2. Fixed the problem of unbalanced DVH output voltage.
  3. Compatible with EcoFlow Wave.
  4. Fixed the problem where the remote control Bluetooth unbinds when the main computer is idle for a long time.
  5. Fixed the problem where the remote control flashes abnormally when the screen lights up.
  6. Optimized the problem of 121 error code in EPS mode.

After the recent debacle with previous FW .85 and being one of the very many affected by the infamous “Error 121” that killed my DeltaPRO, I will refrain from updating for the time being and let the brave souls over at FB do the alfa/beta testing and wait to see how things play out.

Checking the posts over at FB (at time of writing this post):

(2) One user reports that he has better results with the balancing; I say marginally because before the update they were truly bad so it is better but short of the target of an even split.
(5) One user reports that the issue where the remote blinks every x seconds is not resolved for his unit.
(6) For now no brave soul has ventured into doing a REPRO and seeing if truly error 121 has been solved although by the wording I would presume the error is not “fixed” but more like “avoided” maybe with some extra safeguards? … only time will tell I guess…

Those who have done the update report that it took them on average around 12 minutes and they had no issues so at least that’s a positive thing.

Keep an eye on this post as I’ll update it whenever I see new info related to .96

We’re already in October 2022 and people are still reporting the dreaded 121 while on this latest (as of this writing) firmware.

You might want to read this article HERE as there’s a whole section explaining the specific details of ERROR 121.

12 thoughts on “Delta PRO Firmware Review

  • I updated my Ecoflow Delta Pros to v a week ago and until today all seemed fine. Where I am today I have one installed and lo and behold it reports a firmware uddate is require. Once again the mysterious “update from v 0.3.6 to v 0.4.8 has appeared. It’s a completely different number sequence to “proper” updates and this is the “thing” Ecoflow hit me with a couple of weeks back. When I tried the 0.3.6 to 0.4.8 udate then I lost all connectivity with the unit so I shan’t be trying it again.
    I’ve no idea why this anomalous suggested update appears but recall it rapidly ran from 0 to 100% and a “CONNECT” button appeared. I was then unable to connect to the unit after attempting the IOT setup for two hours by which time the language was choice! Leaving it alone for a while, I was pleased to see I could reconnect and found v was installed. I could then update to

    Incidentally, I’ve now seen twoout of five Delta Pros fail catastrophically with a bright flash, loud bang and huge amounts of smoke pouring out of the fan grilles. Both have been replaced by my suppliers.

    I’m now seriously concerned that Ecoflow’s left hand hasn’t a clue what its right hand is doing. This Delta Pro fiasco needs to be seriously sorted out if customers are to rely upon it. Today, I’m very, very wary of my Delta Pros.

    • 19th July 2022. Just to add that all FIVE (not all in the same location) of my DP’s are saying they need a firmware update from v 0.3.6 to v 0.4.8.

      Comeon Ecoflow, what on earth is going on?

  • I think the problem of the 121 errors has always existed, but the firmware made them more common. I have read numerous stories (going back to January/February) in the Facebook group of people using the DP in EPS mode when eventually it blew smoke and stopped working.

    My personal experience was that my first unit ran fine until an update near the end of April ( or This update had a change in EPS mode where the relay switching time could be intermittently slower than previous releases, causing many of my loads to shutdown/reboot. I reported this change to Ecoflow and requested a firmware downgrade. I can only guess, but I think they did something to improve the switching time of the transfer switch in the release, and perhaps made it intermittently too fast causing AC to input into the inverter/charger after the inverter mode had already started.

    The second part of my problem, as I mentioned in the previous comment, they pushed an older version of the firmware to my original unit ( Performing the firmware ‘update’ to this unit bricked the communications module (Wifi/Bluetooth) so I lost all app control over my unit – it was locked into whatever settings I last used it with.

    I received a replacement unit and left it on the firmware due to the slow transfer switching bug that I previously mentioned. It failed after about 3 week at the moment it switched from pass-through to inverter mode. I think the error code I received was 320 (I’m only certain it wasn’t 121). With nothing to loose, I updated to firmware on that unit and the reported error code changed to 121. So, I think 121 is an error code implemented in a more recent firmware version, but the underlying problem existed going back a long time (perhaps not with the same occurance frequency).

    I’m now on my 3rd unit, and I’ve purchased a 72v switching power supply with power factor correction and I’m only charging this DP via the DC input to avoid activation of the transfer switch and toggling between inverter/charger modes. So far, no problems, but I’ve lost a lot of round-trip efficiency with this new charging setup.

    • Hi again Rick.
      First of all, thank you for your time writing such a detailed to-the-point explanation.
      I actually have to concur as I’ve observed a couple of times prior to the dreaded 121 an error code 122 but nothing broke and what I witnessed was a very fast toggle of the relay switch on/off/on/error-122. I also was able to reproduce a surge of up to 245V from the DP, caused by a Samsung monitor that I have which would trigger my big UPS that is protecting all my sensible/expensive equipment.
      90% of the time I use my DP with solar input and never with AC Passthrough. Recently I got a second DP and I decided to hook one DP to the other so I actually was in EPS mode (tons of solar input so not too concerned about efficiency).
      That is when the first DP kicked the bucket and went up in smoke…
      As we are piecing together the bits and pieces of this 121 issue, it feels more and more to me that it is a hardware design failure so if that turns out to be true, it would be good to at least uncover the triggers/situations to avoid them as it is not fun to have a minimum of 2 week downtime.
      I for one have avoided EPS/PASSTHROUGH like the plague since getting error 121.
      I’ll include all this info in the upcoming article, if that’s ok with you.

      • I suspect, but can’t be certain, that the issue may be able to be avoided by not fast switching between inverter & charger modes. I.e. by turning off the AC output to ensure the inverter is turned off and/or won’t immediately turn on when plugging/unplugging the AC input.

        I’m not sure I feel brave enough to AC-charge a DP again, but if I do I would try this approach first before trusting the EPS mode functionality.

        • In my case I use solar charge exclusively but if I have to use AC I make absolutely sure there’s no possibility of entering EPS mode.
          I sincerely hope this gets clarified & (truly) fixed asap.

  • I have had to return BOTH my original DP’s that I originally received Feb 3-2022.

    So in my case, I have a whole house Reliance Controls TCA1006D 100-Amp DP Single Load Transfer Switch.

    This transfer switch is fed from Reliance Controls PB30 L14-30 30 Amp Generator Power Cord Inlet Box (for Up to 7,500 Watt Generators) and is connected to my Reliance Controls TCA1006D 100-Amp DP Single Load Transfer Switch.

    When I switch back to grid power from DP power at the transfer switch, I am only disconnecting the “hot wires” (red and black)

    So the neutral and ground are still connected to the PB30 L14-30 30 Amp Generator Power Cord Inlet Box and the cord between the PB30 L14-30 30 Amp Generator Power Cord Inlet Box and the Double Voltage Hub (DVH)

    My overload issue occurred when I plugged the both DP’s into two dedicated 120 volts AC receptacles each with its own 20 amp breaker connected directly to main panel.

    Is it possible there is some kind of feedback loop occurring on the neutral wire?

    When i received my 2 NEW DP’s, I decided I would NEVER used these two dedicated 120 volts AC receptacles each with its own 20 amp breaker while leaving the cord connected between the PB30 L14-30 30 Amp Generator Inlet Box and the DVH.

    Last Friday, with the SOC of DP’s down to 35%, I was not getting sufficient solar power from my arrays (only about 300 watts), so I connected both DP’s to the 120 volts AC 20 amp receptacles WITHOUT disconnecting the cord between the PB30 L14-30 30 Amp Generator Inlet Box and the DVH.

    Please keep in mind, the Reliance Controls TCA1006D 100-Amp DP Single Load Transfer Switch had been set to “grid power” prior to to plugging in the DP’s so the power going on to the DP’s would have been coming from the grid.

    However, upon plugging in both DP’s to the AC outlets, neither DP showed ANY increase in input watts even though my EF App was set 1,800 watts.

    I immediately detected a slight burned plastic odour. I immediately unplugged both DP’s from the 120 volts AC receptacles.

    I looked down and realized the cord between the PB30 L14-30 30 Amp Generator Inlet Box and the DVH was still connected.

    I unplugged it at the DVH end, replugged the both DP’s into the 120 volts AC receptacles and now DP’s both displayed 1,950 watts if input power coming in and NO burned plastic odour.

    I left both DP’s plugged in until they reached 100% SOC and carried on using them as usual since then.

    You may or may not have seen Will Prowse’s You Tube video ( where he fried one of his DP’s when he made a neutral grounding plug.

    Is it possible that because my neutral is staying connected via the cord between the PB30 L14-30 30 Amp Generator Inlet Box and the DVH that I am getting some kind of feedback loop?

    • Hi Kevin,

      Thank you for taking the time to write your detailed post. Yes I have seen Will Prowse’s video and I think he was onto something there but he didn’t take his investigation any further… bummer…

      I’m located in the EU so our standard setup is different than yours which I presume is US.
      Ecoflow have taken a big gamble on the design and come-to-market with the DeltaPRO. It is a great device but I think it needed a little bit more time to properly mature.
      Maybe some of the things it can do had been rushed to hit a release date and I’m sure they will greatly improve & fix the flaws with the DP2 but for now we would like the DP1 to work flawlessly so we actually forget about it.

      I’m not an electrician but the first thing I would tell you is to not share/mix the neutrals from different sources and to get a tester and check different voltages to understand what is going on there (take all necessary precautions!).
      One engineering principle is to keep it simple so I would start there. The simpler it is the less chance of a mistake or an unforeseen error/problem.

      In my case I treat the DP as something that is quite delicate as I know it’s flaws and shortcomings so I work around them to avoid problems and extended downtime as this system is running 24/7/365.

      For the time being, pending confirmation of a detailed analysis, explanation and (possible) fix from EF, I would avoid EPS mode at all.
      In my case I have the DPs isolated via ATS and they only feed from solar (3.2KW 2 arrays). If batteries are depleted then the ATS switches to grid and bypasses the DPs. When solar is back the DPs will wake up automatically and start recharging. Once there’s AC coming out of DPs the ATS will switch back to them.

      To give you an idea, for the month of june I pulled a total of 8KW from grid and the rest (360KW) was from DPs (it’s an isolated room that has all electronics/gear/etc).

      TLDR; don’t use EPS until EF publicly clarifies what is going on and that it has been fixed.

  • Hi All!
    I’ve been receiving requests and questions about many different aspects of the DeltaPRO that I’ll be addressing in the upcoming article so hang on and give me a little bit more time and after the article I’d be happy to setup a chat/youtube/etc to answer all your questions and doubts to the best of my abilities.
    I also want to thank you all for taking the time to visit Dringlord 🙂

    • Just letting you know I’m really interested in the upcoming article and I’m checking this blog almost daily for updates. I hope it will be ready soon.

      • HI!
        Yes it’s almost ready and should hopefully be published this week. Actually I’ve been working on 2 articles, this one and the EB one so a lot of interesting findings and solutions to most common problems.
        I’m also thinking about doing a LIVE video (like twitch maybe?) where I’ll try to answer everyone’s questions about the DP to the best of my ability if that’s something that would be interesting to everyone…
        Thank you for your patience and for taking the time to post here! 🙂

  • Pingback: EcoFlow Delta PRO 6+ months review – DringLord

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.