Heat pump amps spiking (Fixed)

[Solar Guppy]

Doubtful. It's fine on battery and grid power. Just does not like mppt. I changed the solar priority to power the load first and than charge battery. I don't think it matters much but who knows. I think I might have to return it and get something else. I should not have to fix a perfectly working heat pump.

I understand your feelings, but the reality is that a 6kw inverter is in no way enough wattage to power any home that keeps large whole home heat pumps on the critical load panel.

You can power them, but you are going to need more batteries to prevent sags, more solar ( I have 11kw ) solar and likely an inverter based heat-pump.

I replaced my York heat pump with a ducted 2-3 ton mini-split ( MrCool ) but I don't have a well pump to deal with either. Look at it this way, you have a 200 amp main?? and an inverter that is rated for 30 amps expected to power the home? ( guess based on your grid comments in the thread )

 

[nc73]

I understand your feelings, but the reality is that a 6kw inverter is in no way enough wattage to power any home that keeps large whole home heat pumps on the critical load panel.

You can power them, but you are going to need more batteries to prevent sags, more solar ( I have 11kw ) solar and likely an inverter based heat-pump.

I replaced my York heat pump with a ducted 2-3 ton mini-split ( MrCool ) but I don't have a well pump to deal with either. Look at it this way, you have a 200 amp main?? and an inverter that is rated for 30 amps expected to power the home? ( guess based on your grid comments in the thread )

6k is enough I am no where near 6k useage. I only power the heat pump and maybe the well pump for a few mins that is it. I don't use beyond 1800 watts at a time. If I did it's only for a few mins past 1800. The heat pump uses 1650. The issue occurs when the heat pump is the only thing running and I'm drawing 8 amps max if you count other things in the house. Again it runs fine on batteries. It's only when the charger kicks in it does it sometimes. Now if 2 inverters would fix the problem I would get another but no one knows and that's a lot of wasted energy running 2 with barely any load on it. I emailed MPP Solar, so probably won't hear back until next week sometime. Watts247 has been great with suggestions. I just don't want to keep playing with it and potentially killing my compressor in the process with unknowns.

 

[Ampster]

ut the reality is that a 6kw inverter is in no way enough wattage to power any home that keeps large whole home heat pumps on the critical load panel.

Yes my heat pump in winter draws about 700 Watts which amounts to 10 to 12 kWhs overnight. I have a bigger pack but also use credits accumulated during summer to support those loads of there is not enough solar to recharge my pack and I have to use grid at off peak to charge my pack..

 

[nc73]

Ampster build yourself a battery...mine is 15kwh battery. I have to turn my well pump on during the day because I produce more than I need from the panels and nowhere to store it. I fill my huge pond with it.

 

[nc73]

Can anyone tell me if the graph below is normal for inverters? I am not connected to Grid power yet I see grid spikes. Not sure if the ac output voltage drops is normal or not.

 

[Solar Guppy]

What is the sampling rate?

To see what is really going on you need 1 second samplings, most inverter manufacture stuff that uses the solarman portal is 5 minute sampling

The X axis on the Grid voltage numeric don't seem to make sense?

 

[OzSolar]

The X axis on the Grid voltage numeric don't seem to make sense?

I'm not familiar with that software but it looks like it's autoscaling down to a meaningless range and reporting noise that can likely be ignored.

 

[Solar Guppy]

I'm not familiar with that software but it looks like it's autoscaling down to a meaningless range and reporting noise that can likely be ignored.

Make sense, Grafana does that and the OP mentioned the grid is not connected, still wondering on the sample rate

 

[nc73]

Solar Assistant only does 10s or more. I see a spike that was 60volt...that is super low. granted it's a spike. It would be great if someone can confirm if this is normal.

 

[nc73]

 

[Solar Guppy]

Solar Assistant only does 10s or more. I see a spike that was 60volt...that is super low. granted it's a spike. It would be great if someone can confirm if this is normal.

That is to slow to see what is really going on, likely the transients your looking for will not be shown due to sampling. If you caught a 60V one, you have big issues, and I better it will match a large load turning on, likely a motor.

OK you posted as I did, yes that is not good, and with a higher sampling will likely see its much worse. more often

 

[nc73]

That is to slow to see what is really going on, likely the transients your looking for will not be shown due to sampling. If you caught a 60V one, you have big issues, and I better it will match a large load turning on, likely a motor.

OK you posted as I did, yes that is not good, and with a higher sampling will likely see its much worse. more often

Yeah that was a 10s sampling. It could be due to the well pump coming on possibly. I have not used the heat pump today. My issue only occurs if the mppt is charging, so a really sunny day is what I need.

 

[Solar Guppy]

Yeah that was a 10s sampling. It could be due to the well pump coming on possibly. I have not used the heat pump today. My issue only occurs if the mppt is charging, so a really sunny day is what I need.

To characterize your specific loads, you need a DVM that does inrush peak amp capture, the one I have is a Mastech MS2018, great meter.

If this is only a charging using solar and motor peak startup load, sounds like you a have found a bug in the firmware, which doesn't surprise me, stuff from China, you are the beta tester. AIO are complex and China doesn't do much more than lab test and ship.

 

[nc73]

To characterize your specific loads, you need a DVM that does inrush peak amp capture, the one I have is a Mastech MS2018, great meter.

If this is only a charging using solar and motor peak startup load, sounds like you a have found a bug in the firmware, which doesn't surprise me, stuff from China, you are the beta tester. AIO are complex and China doesn't do much more than lab test and ship.

I do have one of those. I know my heat pump now starts at 14amps after installing the soft start and settles at 6.9amps. As far as I can tell the voltage drops are occurring a bit too often and is probably killing my compressor. Some how it does not like when the inverter is charging the batteries.

 

[nc73]

Solar Guppy I might have to try your suggestion since the inrush current is 61 for the well pump and the heat pump is around 80 so it should work if I were to remove the soft start. Still a difference of 20 but it might be able to start it. I just hate to take it out since it works at all other times.

 

[timselectric]

I don't think that is the problem.
But, good luck.

 

[nc73]

I don't think that is the problem.
But, good luck.

I don't think so either. Just to confirm I checked and indeed the 60v drop is the well pump. The heat pump with the soft start does not drop much.

 

[Solar Guppy]

Well this unfortunately is what comes with buying low budget Chinese equipment, you are the quality control / beta tester.

With in additional input you have added, I think your AIO has bugs as you have pointed out with charging, and as you dig deeper you will likely find other issues.

This is what is not covered by promoting the anyone can do solar, click my affiliate link to buy now mentality. 95% of the stuff out there is marginally functional and not code listed, maybe so far as to say junk?

The more expensive and mature products may not seem worth the higher price, that's until someone like you comes along and finds out, there is no free lunch and spends week if not months chasing issues. Even when you have proven its the equipment, you will get crickets.

If your goal is to power your home, you likely need to look else where would be my advise, time IS money, and your spending lots right now.

 

[nc73]

Well this unfortunately is what comes with buying low budget Chinese equipment, you are the quality control / beta tester.

With in additional input you have added, I think your AIO has bugs as you have pointed out with charging, and as you dig deeper you will likely find other issues.

This is what is not covered by promoting the anyone can do solar, click my affiliate link to buy now mentality. 95% of the stuff out there is marginally functional and not code listed, maybe so far as to say junk?

The more expensive and mature products may not seem worth the higher price, that's until someone like you comes along and finds out, there is no free lunch and spends week if not months chasing issues. Even when you have proven its the equipment, you will get crickets.

If your goal is to power your home, you likely need to look else where would be my advise, time IS money, and your spending lots right now.

I completely agree. I'm willing to see this through though and if I have to I will get my money back some how. At least I have grid to fall back on, some do not. Here is the final comparison, first graph is with full sun and mmpt charging, that's when I see the spikes in heat pump amps. Second is just batteries and barely any mppt activity, no sun, etc. Anyone out there with a heat pump and thinking about getting one of these inverters, think twice.

 

[Solar Guppy]

I don't think so either. Just to confirm I checked and indeed the 60v drop is the well pump. The heat pump with the soft start does not drop much.

Well the good news your doing all the right things, and learning for example any motor load is a challenge for ANY RE system. As I wrote before, if the heat pump running caused loss of AC regulation of the inverter ( you mentioned voltage all over the place and something making sounds in the heat pump ) you have multiple concerns. The loss of regulation is a sign there are firmware issues with the loop control logic ( software ) in the AIO. Its a highly complex environment the DSP's have to manage different functions in the AIO. Doesn't surprise me in the least.

The reason I suggested removing the softstart is from the AIO control, a load that draws high current and then halfway up the ramp of the sinewave changes drastically due to the triac turning off the compressor load, I could see would be quite a challenge to keep regulation. So in the process of narrowing down the cause I would remove to rule or confirm if this is the case.

The other avenue is you know that charging via solar is causing the voltage output to lose regulation, start disconnecting loads to see when it stops the behavior, but keep charging as that make the issue present. This is just deductive reasoning for trouble shooting.

This is an interesting case!

 

[nc73]

Well the good news your doing all the right things, and learning for example any motor load is a challenge for ANY RE system. As I wrote before, if the heat pump running caused loss of AC regulation of the inverter ( you mentioned voltage all over the place and something making sounds in the heat pump ) you have multiple concerns. The loss of regulation is a sign there are firmware issues with the loop control logic ( software ) in the AIO. Its a highly complex environment the DSP's have to manage different functions in the AIO. Doesn't surprise me in the least.

The reason I suggested removing the softstart is from the AIO control, a load that draws high current and then halfway up the ramp of the sinewave changes drastically due to the triac turning off the compressor load, I could see would be quite a challenge to keep regulation. So in the process of narrowing down the cause I would remove to rule or confirm if this is the case.

The other avenue is you know that charging via solar is causing the voltage output to lose regulation, start disconnecting loads to see when it stops the behavior, but keep charging as that make the issue present. This is just deductive reasoning for trouble shooting.

This is an interesting case!

I will start with removing the soft start, but will have to wait for a sunny day to test it. that could be days and days. Will try removing loads as well and the only one really is the fridge. I don't have much else plugged in. Thanks for the suggestions! Hopefully MPP Solar will get back to me next week.

 

[nc73]

So which off grid inverter out there will do the job? I'd be willing to entertain the high frequency ones if they can start the well pump. I don't mind spending money on something that works but was under the impression mpp solar wasn't so bad.

 

[Solar Guppy]

So which off grid inverter out there will do the job? I'd be willing to entertain the high frequency ones if they can start the well pump. I don't mind spending money on something that works but was under the impression mpp solar wasn't so bad.

Schneider Electric XW-6848 ( close to 20 years of proven history ) but you build a system it is NOT a AIO or the Sol-Ark , a modern China ( Deye ) designed AIO that Sol-Ark has control of the firmware, meaning good USA support as issues are found as the customer base increases in size, they get addressed.

I have a pair of Solis 5G HVES they are setup to Grid tie my solar and provide most home backup with a BYD batterybox ( 400V , not 48V ), but this is never intended to be anything more than a backup system ( I live in Florida , Hurricanes ), would not recommend for whole home / off-grid type application

 

[nc73]

Schneider Electric XW-6848 ( close to 20 years of proven history ) but you build a system it is NOT a AIO or the Sol-Ark , a modern China ( Deye ) designed AIO that Sol-Ark has control of the firmware, meaning good USA support as issues are found as the customer base increases in size, they get addressed.

I have a pair of Solis 5G HVES they are setup to Grid tie my solar and provide most home backup with a BYD batterybox ( 400V , not 48V ), but this is never intended to be anything more than a backup system ( I live in Florida , Hurricanes ), would not recommend for whole home / off-grid type application

That is not a bad price but I'd have to change my panel configuration since I do not see any mppt's that can handle 7 400watt, 49voc in series...Oh boy will def have to get this thing fixed.

 

[Skypower]

Since the inverter can handle the well pump, I'd remove the soft-start to see if it is the cause, and yes, it should only engage when on turn-on, but could be miss-wired or defective.

I’m liking that idea. Eliminate the variables.
I installed a new run capacitor and added a two piece type (relay + capacitor) “hard start” , and that made ton of difference reducing start surge. 60 vs 12. I wasn’t going to spend $350 on an Easystart on a 22 year old AC knowing that it probably isn’t needed on the a future unit. I also installed a “delay on make timer” so the blower starts before the condenser unit and I didn’t like the short to non existent time out delay in the Nest thermostat if there’s a fast power interruption. The blower has a surprising high start current getting that drum up to speed. Things all add up. Everything is well within the the working range of the inverters but this just gives me more safety if someone starts the dryer, microwave and coffee maker.