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Easiest solution to provide generator "boost" for HVAC peak inrush

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I have a Honda 240V inverter generator (EU7000IS) that I use to power my load center via interlock, 30A breaker and input box during power outages. The generator powers the whole house with the exception of my main HVAC unit. What would be the easiest and least expensive way to add a battery backup inverter solution which could pass through the power from the generator and also add power from the batteries during a power surge like when the HVAC compressor starts up? I was looking at the Victron Multiplus units, but they don't seem to have something for 240V that would handle a 60A 1 second surge. Also, what battery would you recommend for a setup like this? Thanks!
 
I have a Honda 240V inverter generator (EU7000IS) that I use to power my load center via interlock, 30A breaker and input box during power outages. The generator powers the whole house with the exception of my main HVAC unit. What would be the easiest and least expensive way to add a battery backup inverter solution which could pass through the power from the generator and also add power from the batteries during a power surge like when the HVAC compressor starts up? I was looking at the Victron Multiplus units, but they don't seem to have something for 240V that would handle a 60A 1 second surge. Also, what battery would you recommend for a setup like this? Thanks!
It will be more easy to answer your question if you post the size of your A/C unit.
Also, your generator may be able to run your A/C if you install a "Soft Start" device on your A/C.
 
There are many soft start kits on Amazon in the $300 - $400 range, depending on the size of your compressor.
 
I have a Honda 240V inverter generator (EU7000IS) that I use to power my load center via interlock, 30A breaker and input box during power outages. The generator powers the whole house with the exception of my main HVAC unit. What would be the easiest and least expensive way to add a battery backup inverter solution which could pass through the power from the generator and also add power from the batteries during a power surge like when the HVAC compressor starts up? I was looking at the Victron Multiplus units, but they don't seem to have something for 240V that would handle a 60A 1 second surge. Also, what battery would you recommend for a setup like this? Thanks!
Did you try starting it off the Generator yet?

You can rig together 2 Multiplus units if needed. 2 MP's linked together each handling 1 Phase.

 
I tried the generator with the soft start and the generator overloaded. Every solution I have researched so far seems to be expensive. Adding a battery bank and inverters with power assist is about as expensive as adding two Ecoflow Delta Pro units feeding my panel via the dual voltage hub ($7k), and using my Honda to charge these during an outage, though I haven't been able to get a solid answer on the surge capabilities of two units in parallel. Getting a second Honda EU7000IS and modifying it to run in parallel on natural gas is likely $6k, and this would waste fuel.

It's almost like I need some kind of supercapacitor just for the second of inrush. I originally had a 5-2-1- hard start on the condensing unit, but that also didn't work.
 
Have you discussed with the EasyStart people yet?
I'd bet one of the MicroAir engineers will have some good ideas for you.

It's been a while, but I think they do offer some type of even larger start capacitor for situations like yours.
 
Yes, I spoke with an EasyStart engineer. He said the problem with my system is that it uses a TXV instead of a piston to regulate pressures. The soft start units have a larger inrush reduction with piston type systems.

The best solution here would be to replace the older inefficient HVAC unit with a mini split, but the cost would also be high and my unit is still working fine on utility power. We may be moving soon within the next couple of years, so I don't want to throw too much money into the house. This was the reason for getting a portable backup generator as opposed to a standby unit...we can take it with us when we leave.
 
Yes, I spoke with an EasyStart engineer. He said the problem with my system is that it uses a TXV instead of a piston to regulate pressures. The soft start units have a larger inrush reduction with piston type systems.

The best solution here would be to replace the older inefficient HVAC unit with a mini split, but the cost would also be high and my unit is still working fine on utility power. We may be moving soon within the next couple of years, so I don't want to throw too much money into the house. This was the reason for getting a portable backup generator as opposed to a standby unit...we can take it with us when we leave.
Then just get a portable ac unit for keeling one room comfortable and take that with you when you leave as well.
 
Soleus Air makes a window air unit that hangs over the window sill. It might work to cool an area. Would work better/more efficient than the portable.


Maybe one of those to use during an outage then take back out? Easy to take with or sell later once you move.
 
All of my windows are casement style instead of double hung, so those types of ACs won't fit. I'll look into the portable ACs, though I doubt they are very efficient or offer a lot of cooling.

I do have a mini-split in the basement that runs without issue on generator power, so it's not like we'd die of heat stroke or anything...but it would be nice to be able to use the rest of the house if we had an outage during a heat wave.
 
All of my windows are casement style instead of double hung, so those types of ACs won't fit. I'll look into the portable ACs, though I doubt they are very efficient or offer a lot of cooling.

I do have a mini-split in the basement that runs without issue on generator power, so it's not like we'd die of heat stroke or anything...but it would be nice to be able to use the rest of the house if we had an outage during a heat wave.
I would just stick with that then. Sorry, that is more motherly than technical advice. ?
 
That looks like an awesome battery setup. I'm guessing that full rack with a split phase inverter is well over $12k. Would certainly be a worthwhile investment if I had solar panels and could save on grid electricity, but now we're talking big bucks.
 
I would add the Victron Multiplus of sufficient capacity and a 4+ hour battery to boost the generator power.
Otherwise just sweat it out with a fan.
 
Also, is it really necessary to run a 4-ton A/C during outages? For outages, some electricity usage and convenience reduction is common so it seems a few inexpensive portable 8K or 12K BTU A/C's should be adequate to keep enough rooms cool?
 
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You would think there would be a market for a portable generator booster which could plug into any generator output and serve as a passthrough unit until such time as a short term boost is needed. Then, an included battery/inverter combo could provide the boost and then return to charge/passthrough mode. I bet this would sell like hotcakes.
 
You would think there would be a market for a portable generator booster which could plug into any generator output and serve as a passthrough unit until such time as a short term boost is needed. Then, an included battery/inverter combo could provide the boost and then return to charge/passthrough mode. I bet this would sell like hotcakes.
Victron Multiplus
 
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