Comparing Self-Balancing Feature of ERVs
I’m comparing 2 different ERV models, I’m wondering which is better at ‘self-balancing’
The 2 modles are the Panasonic FV-10VEC2 and the Vannee A.I V150E75NT.
One guy had shown me the Panasonic says it has ‘intellibalance’.
But then a while later someone from another company said that the Vanne AI series has ‘true’ self balancing. That the Panasonic still has to be balanced by a technician and then tries to auto-balance from that point. And that the Panasonic doesn’t have a pressure sensor in it like the Vanee does. So the Vannee A.I continuously self-balances right from the beginning, which is superior.
Is it accurate to say the Vanee A.I is that much better than the Panasonic in that regard?
It’s hard for me to tell someone is just hyping the brand they deal with most.
I had heard the Panasonics were so much newer and more advanced so I’m feeling confused.
Thanks for any feedback.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
There is nothing in the Van E literature, troubleshooting, or wiring schematic in their manual to indicate the presence of a pressure sensor. From what I understand, these units use an internal look up table using torque and RPM to calculate the air flow. It sure looks like both units use the same method to set motor speed, but VanEE's control on that ERV looks a bit more sophisticated. For example, the installer can choose from two fan speed options controlling defrost mode, something not offered by the Panasonic. In particular, the "Advanced Touchscreen" digital wall control that VanEE offers as an option in these units does not have a comparable on the Panasonic 100 unit. You'd need to purchase the 200 CFM Panasonic unit to get this option.
Ok, I went over what the tech guy had said. He points out that the Vanee AI ERV
"has no balancing ports for the techs, so it auto balances all the time, based on the indoor/outdoor humidity and temperature and the pressure differential between the two"
Then later on the Panasonic says "it only adjusts based on temp and humidity it doesn't actually have any pressure sensors in it."
So I guess he strongly implies the Vanee A.I has a pressure sensor in it, without explicitly saying it does, so that's why I thought that. And saying it measures the temp and humidity does sound very similar to what the Panasonic does.
So maybe he was bluffing, for the models he caries? Or didn't know that much about the Panasonic. There's some reason the HVAC guys are not brand neutral I'm not on top of.
Greg, so first of all, with no wall controller, neither will respond to humidity...that's measured at the wall control. They also do not respond to outside temperature aside from detecting defrost conditions, but the Venmar unit, might be able to vary defrost times (not sure on that feature). Both units will vary motor speeds based on what you select for delivery CFM, pressure in your home, and more importantly, static differences inherent in the ERV/core itself and your ducting.
On the Vanee, their own motor blurb does not mention anything about pressure sensors: https://www.airsolutions.ca/images/Products/Venmar/Venmar-N-Series-Quick-Reference.pdf
In fact, the first line is pretty informative " Set the CFM and the unit auto-balances and self-adjusts—algorithm tested" This strongly suggests they are using RPM and torque like everyone else. I don't see any need for a pressure sensor if you can monitor RPM and power constantly.
My take on the Broan so called "AI" unit, (it's not AI), is that their control electronics are more advanced. You can deduce this from the error codes in the manual that trigger say if a motor cannot meet the CFM target that you have set. Similarly, if you fire up your 2000 CFM kitchen exhaust in a tight house, the fresh air motor would require less torque/rpm to meed your set CFM target, so it would slow down, but the exhaust fan would likely speed up again to meet the CFM target you set as it would working against your super duper kitchen exhaust. But it can only balance limited by max power of each motor.
The error codes also suggest that the Venmar, like the Panasonic has limits in terms of static differences that it can overcome, and this will throw an error if say you're asking for 130 CFM on the fresh air side, with a restrictive duct system, blocked exhaust etc. My take on the differences between the two is that the Venmar will tell you this via the display/error codes, whereas the Panasonic will not...you'd need to verify with a differential magnehelic.
Hope that makes sense. Both units are fine...it's just that the Venmar has better control electronics in my opinion. Remember that HVAC techs sell you equipment with varying differences between their cost and retail. They also have preferred dealers with respect to after sales service and will steer you that way based on their own experience providing service to customers. Venmar has been in the business a long time, and has a long track record with trades folks, particularly here in Canada.
Wow, thanks for all that info.
If you don't mind there was another feature comparison, the cold climate tolerance.
You mentioned the defrost mode fan speeds on the Vannee, which sounds promising.
By one HVAC tech I was told that the Panasonic is specifically made for 'cold climate' and won't freeze up in -30 like others will. I understand it detects the temperature in the core and then lets air in shorter spurts to avoid freezing.
The other guy pushing the Vanee AI, insisted the A.I series is newer and more advanced than the Panasonic. Apparently it prevents freezing by exhausting more warm air from the house while letting less cold air in to prevent freezing.
[b]But I can't find exact temperature guidance on the Vannee, if you have any idea where I could check that. [b]
I did find documentation for the -30 Panasonic here:
QUOTE BELOW FROM THIS LINK
https://na.panasonic.com/us/home-and-building-solutions/ventilation-indoor-air-quality/energy-recovery-ventilators/intelli-balancer-100-any-climate-erv-corded-model-50-100-cfm
"OPERATION IN EXTREME TEMPERATURES
"FV-10VEC2 (Cold Climate Model): Recommended for areas where temperatures can drop as low as -22°F (-30°C). When the outdoor temperature is < -22°F (-30°C), the defrost cycle is initiated and the product will stop operating for 47 minutes, then operate in heat exchange mode for 4 minutes in order to sample the outdoor temperature. It then operates in circulation mode for 9 minutes in order to defrost (exhaust and supply air are 50 CFM). Defrost cycle overrides the ASHRAE 62.2 timing function."
Ok, so a bit to process there...and it sounds about right.
Unbalancing an ERV/HRV during defrost effectively unbalances the house, pulling in cold air via leakage. Panasonic does not do this on the FV-10VEC2, but rather engages a recirculating damper that blocks fresh air while circulating inside air to warm the core. It does this on a schedule/table based on outside temps as they drop below -10C. The quote you provided only reflects operation when temps drop below -30C.
VanEE's documentation on the wiring section only provides: "RecirculationDamper (J6 ) is not present for all models" so it's possible they are not using one on the ERVs and going to exhaust only for defrost. That reduces cost on the unit, but in my opinion is not great for efficiency overall. Additionally their numbers would not reflect the loss in house efficiency (pulling in cold, dry air via leakage) during defrost cycles.
Renewaire takes a different approach, suggesting that no defrost is required at all, unless inside humidity is extreme, as you'd find say with a pool house.
You'll see efficiency numbers drop quite a bit as temps hit -25C across the board for most ERV/HRV as the testing accounts for loss during defrost cycles, where warm room air is heating the core and no air exchange is taking place. The exception would be Tempeff's dual core system that has no defrost cycle: https://www.tempeff.com/wp-content/uploads/2023/11/14094-Tempeff_RGSP-K_Sellsheet.pdf
I finally ordered a Broan AI ERV today which seems to be essentially another label for Venmar. Reading through the manual for B210E75RS for setup it describes an autobalancing procedure which mostly involves turning off various intermittent exhaust fans (bath, dryer, range hood), turning on the central forced air system handler if the ERV will be ducted into that, closing all windows/doors, and telling it which version of duct configuration you're doing (to hvac, or on it's own ducting). Then the ERV runs and tells you how many CFM it can do in/out with the current duct setup and you can adjust max/min preferences or work on improving duct setup if it's not fast enough. Other broan models have 4 holes in the back to insert probes for professional balancing but supposedly the AI version doesn't need that and the holes are omitted. When I install the ERV over the next month or so provided it arrives soon we'll see how smoothly it all goes.
Keep us posted. I wasn't aware of those units. They are surprisingly inexpensive, too. The 130 cfm model is about the same price as the Panasonic 100 cfm model. The Panasonic looks to be a bit more efficient but does not have the "AI" balancing feature that the Broan has.