AO Smith HPHW Error Code

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sloeffle

Minister of Fire
Mar 1, 2012
1,286
Central Ohio
We've had our AO Smith 50 gallon HPHW for about three years now. It has run flawlessly since we've put it in until this past month or so. A few weeks ago the HPHW had an ECC error code on the display. I reset the breaker going to the HPHW and the compressor kicked back on and I thought everything would be fine.

Went out of town last week and noticed that my electric usage was running higher than normal via app on my phone. Came home and the compressor isn't running again but with no code. I reset the breaker again and now on startup I'm getting a P5 code. Called AO Smith and they told me to clean the drain. Powered the water heater off and cleaned the drain and now it seems to be running fine but it still sometimes flashes the P5 code sometimes. From what I can find via the online manual, P5 means "suction temperature". Any HVAC pros have a clue what that means, and what the problem could be ?

Online AO Smith Manual - https://www.hotwater.com/lit/training/100268628.pdf
 
I was finally able to get ahold of a local HVAC person yesterday. He told me that the condensing coil is probably dirty. He recommended blowing it out and seeing if the code goes away.

As I understand it from talking to him on the phone, suction temperature is the difference in temp between when the refrigerant enters the condensing coil and leaves the condensing coil.

 
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Yesterday, the heat pump stopped working along with an ECC error code. Called AO Smith and they had me do a couple things but the code still came back. Called tonight and they replacing the unit for free. Now that is customer support.
 
How old is it? (never mind, I found it! ;lol )
They are replacing the whole HPWH?
 
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How old is it? (never mind, I found it! ;lol )
They are replacing the whole HPWH?
The water heater was built on 11/27/2014. I'm pretty sure I installed it in the spring of 2015.

Yep, they gave me an authorization number to get a new HPHW from a local supplier. He told me the heat pump is a sealed unit and cannot per serviced. I don't understand why they would do that, but there has to some kind of justification.
 
I am on the fence getting a rheem or an AO smith, I am glad to see they stand behind their products. If you go off the reviews at Lowes they come off as shady. Guess I will be going with an AO Smith HWH. The rebates from my local co-op is only $300 so not worth it for the HPWH as it would be $1000 all said and done with me installing it.
 
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Picked my replacement hot water heater up today. I called a local plumbing supply house with the return authorization code, and they had it waiting for me via will call. The only thing I had to do was take the sticker in from my old HPHW.

This new one is actually more energy efficient than the one I had. The new one has a UEF of 3.45, my old one was in the mid 2's.
 
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I am on the fence getting a rheem or an AO smith, I am glad to see they stand behind their products. If you go off the reviews at Lowes they come off as shady. Guess I will be going with an AO Smith HWH. The rebates from my local co-op is only $300 so not worth it for the HPWH as it would be $1000 all said and done with me installing it.
If you buy an AO Smith HPHW make sure you get one with a 10 year warranty. They sell them with a 6 year warranty and a 10 year warranty. It isn't that much more money for a HPHW with a 10 year warranty. The model number should start with HPTU.
 
I ended up getting an AO Smith 50 gallon HPHW, lowes had an open box with a small dent on the back for $699 and I talked the manager down to $599. Took me about 5 hours to get it installed since it was in a tight spot and I had replumb and redo the electrical for it since it is vastly different from my old HW and I had to plumb in the condensate lines.

Found out the $300 rebate from my energy provider only applies to a fossil fuel WH switch out so I was bummed about that, glad I didn't pay the $1299 they originally wanted for it, Lowes made it sound like it was for any WH.

Glad I installed it in my garage, that fan is loud.

Tracking the power use on Sense, my old HW was using about 4500 watts and this thing is using around 1200 watts with the heat pump and eco (top) element on, once the eco element turns off it drops down to about 400 watts with the HP running.
 
Glad I installed it in my garage, that fan is loud.
I finally got my new HPHW installed last night. It is a lot quieter than the previous one. :) The new one has more of a compressor sound, the older one had more of a fan sound.
 
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I think you need the advice of a good HVAC specialist, or maybe not just a consultation, maybe you should call him to look at the errors code on the display? Last year, my sister had a similar problem in her house, error code on the display. We called a company https://appliancerepairinpittsburgh.com/ and their master said that the problem was because of programming failure due to incorrect work of electronic control unit. That all was very quickly fixed and my sister doesn't have any problem now. By the way, this company gives a guarantee on their service.
 
Old thread. Hoping to resurrect, just curious how it’s working out for you guys, installed 80 gallon version. It switched itself from efficiency mode to hybrid on its own. Google got me to YouTube, very good video on there guy explains how to get it to stop doing that. Little more google took me back to my favorite forum!
 
Mines seemingly working well, just because, I tried to change the mode to vacation. It won’t allow me.
I called ao smith. “That’s strange” hold on. Someone else. “Huh. Never heard that before”. There sending a new control board. The customer support/tech help is super friendly but also kinda useless. They seem to have the same manual I have to access and that’s it. I just hope this lasts. I still have old one in place with cold water side still plumbed in bc I don’t yet trust this one yet!
 
My new one has been running flawless since I got it. No complaints so far.