What's going on here

I noticed a massive Spike in usage around 2 am this morning…

A closer look shows some interesting behavior…

Any ideas on what might be going on here?

I’m hoping that this is not a component about to go out as I just received a quote to replace my AC units with new SEER 17 units. I have two 5 ton units and a 3 ton unit. Total for all 3 was $45K…YIKES!

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Here’s a look at the last week…

Big spikes in an AC unit… Wouldn’t be surprised if the runstart (or soft start) capacitor has gone out on one of them. Reasonably easy to check - usually they deform when they blow. Reasonably cheap part if you can figure out that one has blown on one of your units. Somewhat dangerous to replace (240V), but fairly simple to do if you are careful. I replaced one a few years ago based on watching a few YouTube videos. The service call is likely to be expensive, but much, much cheaper than replacement of an AC unit.

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A year or so ago I was quoted around $325 each to add “Hard Start” capacitors to these units. If you are correct and a “soft start” capacitor needs to be replaced should I just go the route of the “hard starts” and be done with it, or is the “soft Start” cap also required?

BTW, I’m very reluctant to mess with anything electrical so will see if my $25 per hour electrician can do this. :slight_smile:

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As @kevin1 stated, capacitor. You probably have a failing compressor and if you install a “hard start” capacitor, can get more use from it.
Your pricing for new units is really high.
I installed a new 3 ton last October for $4800. It’s an American Standard/Trane unit. I did not get the 18 but went for the 16 Seer.
The Seer numbers are misleading. The savings isn’t as much as I thought it would be and why I chose not to get the highest. Would have taken 10-15 to balance the return

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@samwooly1
Yes, I do suspect the pricing was on the high side. I was expecting something around 25- 30K. I put my name down in HomeDepot and that’s the quote from the guy they sent to me. The house is in IID (Imperial Irrigation District) and a SEER rating of 17 gets a rebate of $300 per Ton. SEER 16 = $200 per Ton. I’ll need to do it one day and I’m hoping to delay it for as long as possible. We hit 118F yesterday in La Quinta and it’s been pretty touch on this equipment.

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The box stores often run these ridiculously low “installation specials” for products. But it’s all really built into the price somewhere. I had to shop around as the other two quotes I got were for $8,000 and $10,000.
This guy was a reference from a customer at our store. I’m now using him for our home and business locations. Maybe you know someone that could give a good reference.

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Yikes indeed!

@samwooly1 is right … the big boxes will take you for a ride. Get as many quotes as you can and if you have the stomach, do some research and you’ll save a ton (probably literally). If you want to keep contract bids honest, do equipment comparisons at AHRI, they have a fantastic database:

https://www.ahridirectory.org

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I’m here in expensive NorCal and just had both my 20 yo SEER 10 Bryant compressors replaced, 1 because the downstairs compressor blew out, and the other because it wasn’t really cooling upstairs. I replaced with simple single stage SEER 16 Bryants. Cost me 8000$ for a 4 ton and a 3 ton unit with a local guy. Unfortunately, I think installers take advantage of demand during the peak of AC season to upcharge, especially when the weather gets ugly and people are desperate.

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It appears that this has been happening infrequently, around once per week

It looks like if you could hold out until September 1st (Hmmm) you might be able to get a free check:

https://www.iid.com/energy/save-energy-and-money/your-home/a-c-maintenance-program

[Makes me wonder whether Utility-hosted smartmetering is capable of alerting the Utility if there are short duration load spikes that might indicate residential-side anomalies]

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Nicely spotted. I got in and had one unit serviced via this program in early May before they shut it down and I had a WCC (Western Cooling Circuit) added to one of the units. I think I can holdout to Sept 1. :slight_smile:

Over the weekend I replaced the run/start caps on two of the three units. I also added hard start kits capacitors to all three units.Since doing so, the spikes are no longer as dramatic as they were previously.

The question I now have is, should I delete these devices and let Sense find them again or just leave everything as it is?

Here’s one of the units:
Before:

After:

After:

The new capacitor most likely has a higher storage capacity than the old and the helps get the motor started. This would require less pull upfront.
I’d wait to see if the detections still work on a reliable basis before deleting

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