Lightning surge damage update.

AZjeff

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in Az where the Deer and Antelope play
A few weeks ago we had a near lightning strike that caused a power surge that took out the incoming internet box on the outside of the house, the modem, the doorbell, and the AC. Centurylink replaced the outside box and modem, a new $60 doorbell is incoming, (it's a special AC/DC all in one unit,) and the AC problem turned out to be a fried control board.

I had to call in an HVAC company as I have no way to diagnose but suspected the board. $90 call out charge, tech shows up and checks the ground unit then goes into the attic where the air handler and heating unit are. He replaced the blown 5A blade fuse (that I found and replaced hoping it was the problem,) closed the door switch and heard a relay chatter and said fried board. We came out of the attic and back at his van I gave him the part number off of the board that I had a pic of. He gets out his tablet inputs the part number and says it will be $550 installed and won't be available until next week. Problem is I found the board available from $100 - $200 online at various sources. Told him I knew he didn't set prices but I thought that a bit steep and I may try it myself. This was 3 Fridays ago and we were leaving on a 2 week trip on Sunday. I ordered the OEM board to be delivered ($120) to my daughter so it was waiting when we got home yesterday. Last evening when it cooled down I went up and including taking pics of all the connections and labeling identical blade connectors for location it took me 20 minutes to R&R the board and the AC fired up. A tech who knew where the wires go would do it in 10 minutes. I owned a small business and get costs and profit but that just felt a bit steep. If it was a 3 hour job would be a different story. The HVAC shop is 6 minutes away. Sometimes previous experience pays off.

Interesting that the Centurylink tech and HVAC tech both said it was an EMP from a near strike since it was only low voltage equipment that was killed. No evidence of a strike on our property or the neighboring properties. Next door neighbor says she lost a humidifier.
 
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Wow.. glad you were able to replace it all yourself for a great price! Reminds me of when I was getting the house ready to sell and had to repair the a/c compressor. Two separate hvac companies both (what? it's a trend lately?) tried to sell me a $10,000 new hvac system claiming the existing system was "too old" and repair parts were not available. Not true at all.. 20 min search online bam! new rheem contactor, new fan motor (rheem replacement brand), new capacitor (made in usa too! Titan HD brand), total? $160!

Feels so good when you can do it yourself!

So I can completely relate to your story, there's profit and then there's just plain greed.. and people who want to claim "overhead" for a business go ahead.. They'll just price themselves out of business during this economic spot we're in lately!
 
Problem is I found the board available from $100 - $200 online at various sources. Told him I knew he didn't set prices but I thought that a bit steep and I may try it myself. This was 3 Fridays ago and we were leaving on a 2 week trip on Sunday. I ordered the OEM board to be delivered ($120) to my daughter so it was waiting when we got home yesterday. Last evening when it cooled down I went up and including taking pics of all the connections and labeling identical blade connectors for location it took me 20 minutes to R&R the board and the AC fired up. A tech who knew where the wires go would do it in 10 minutes. I owned a small business and get costs and profit but that just felt a bit steep. If it was a 3 hour job would be a different story. The HVAC shop is 6 minutes away. Sometimes previous experience pays off.
If you think that is bad...

The condenser fan motor died on my parents' 2004-era American Std/Trane Allegiance 14. It is a unique x13 ECM motor with 2 speeds. I ordered one online for $987 and it took me 20 mins to install. HVAC company quoted $1950 installed.
 
Had a similar experience with a control board. Called a tech out ($90) who was kind of chatty but in a good way. Said the unit is old but in great condition and the board is failing, then said “You seem fairly handy and seem to somewhat understand all this. I didn’t tell you this, but it’ll be about $400 and a few days before we can replace this board. You can get one on Amazon in 2 days for about $100-$150 and it’s just plug n play.”

It was indeed plug n play, just followed the directions because the replacement Honeywell board wasn’t an “exact fit” but more of a universal replacement.
 
My business partner had a lightning strike last year. We were at work where we can see the city skyline and we were watching a very dark and ominous storm with tons of lightning just south of us. He had just put in a $150K pool/patio the year before and went home to find all the pool mechanicals fried and most of the appliances in the house fried including 2 HVAC units, all the TVs, and appliances in the kitchen. A neighbor stopped by that evening to see if everyone was ok because they were looking out their backdoor when the strike happened and he said it appeared to hit the approximate area with the pool equipment. Insurance was kind of a nightmare and while the process of determining which appliances were affected was straightforward the process of trying to figure out which hidden items like wires and outlets were affected sucked.

There were outlets and wires that were melted. The back of a TV was melted. There were issues with supply chains and being unable to get replacement parts. Lightning can really do some damage.
 
AZjeff, a repair like yours's has to make you feel good / self-reliant.

It has to be difficult (or impossible) protecting electronics from a lightning strike.
How much help would a Whole House Surge Protector have helped?

One good idea would be to unplug any electronics during a thunderstorm.
Not just turn them OFF, but actually unplug.
 
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So all total how long were you without A/C?
Hi Bill. We were out for 5 days then we went traveling for 2 weeks. It was in mid 90s while we were here and the house got to 81-82 in the late afternoons so liveable. Daughter checked the house every couple of days and the thermostat never showed above 80 when we were gone.

I don't know if a whole house surge protector would have protected the low voltage stuff since it didn't pop any breakers. Funny I learned of the WHSPs recently and was researching them on and off. If it was an EMP maybe not since that radiates from a point and wouldn't necessarily come through the box. But a good idea.
 
A typical lightning flash is about 300 million Volts and about 30,000 Amps. Other than lighting rod protection don't know of any for a direct hit. Look at Artemis 1 rocket they protected it by three towers.
 
for sure besides saving $$$$ the satisfaction of DIY is PRICELESS, especially after getting a crazy take you to the cleaners price!!
 
I don't have much faith in whole house surge protectors, I think they're kind of snake oil. Lightning will take the shortest path to ground--whether that's through your home and equipment, and then out through your AC panel ground, or through grounds placed outside your home.

I added two ground rods, each spaced 16' from my AC entrance panel ground, and then bonded them all together. I also made sure that the telephone/DSL NID and CATV service drop grounds were bonded to it as well.

If you have the opportunity to look at commercial tower or telephone central office grounding systems (and of course I recognize most people don't have that option), the grounding systems are very significant. They don't use contraptions, they simply provide many short paths to ground, and all bonded together with a large copper bus bar.

My point is that any cable entering your home basically acts as an antenna to channel lightning energy either directly, or through induction (EMP) into your home. Every single outside cable needs to have an outside ground, and if you have multiple outside grounds they all need to be properly bonded together.

If you're thinking this all sounds pretty complicated, you're absolutely right. This is why God gave us Electricians who are familiar with the National Electric Code, which covers proper grounding. If you've ever had lightning damage, or you're concerned about it, it's WELL worth the money to pay a licensed electrician to come out and verify the grounding on your home is done properly, and whether you can effectively enhance it, and what it might cost to do so.

I know there are those who will say that there's nothing to be done about lightning strikes--they're going to damage what they're going to damage and there's simply nothing we can do to prevent it. That's absolutely and completely wrong.
 
If you have the opportunity to look at commercial tower or telephone central office grounding systems (and of course I recognize most people don't have that option), the grounding systems are very significant. They don't use contraptions, they simply provide many short paths to ground, and all bonded together with a large copper bus bar.

Central offices DO in fact have lightning protection on the incoming lines. It looks like this:

1670545492108.png


You'll find blocks with those plugged in. One per copper pair. Right on the MDF.

They look like this:

1670545673802.jpg
 
Another thing central offices and radio transmitter buildings and datacenters and other things have is an Ufer ground.

That's where the building ground is connected to the rebar in the foundation.

Drive as many ground rods as you want, it won't be equal to what an ufer ground provides.

BTW, ufer grounds have been required by the NEC for residential homes for several years now.
 
Old post, but you might want to check to make sure any jumpers were set to the proper settings as well - not just the wiring. Some more modern boards have jumper settings for fan speeds and each mode and some other things. Not an expert - just been there, done that. Just copy what was on your old board if you still have it - or can see in your photo's
 
Another thing central offices and radio transmitter buildings and datacenters and other things have is an Ufer ground.

That's where the building ground is connected to the rebar in the foundation.

Drive as many ground rods as you want, it won't be equal to what an ufer ground provides.

BTW, ufer grounds have been required by the NEC for residential homes for several years now.

Sure, but that's only for new construction for the last several years. This is why I highly recommend hiring a licensed electrician who can advise you on how practical/expensive it would be to bring grounding up to current code on an older home.

If you have an older home that predated that requirement in the NEC for a Ufer ground, then adding a few extra ground rods, and maybe even bonding to an existing well casing could be a perfectly workable, effective and cheaper alternative. Simply because a guy has an older home and may not be able to implement a Ufer ground doesn't mean he should throw up his hands in futility and say, "well, I can't do a Ufer ground, so it's pointless for me to try to improve the grounding I have..." That just doesn't make any sense at all.

Regardless, the single best course of action for a homeowner to take if he/she is concerned about potential lightning damage is to hire a licensed electrician. The electrician can guide the homeowner through practical options and costs.

I have an older home and don't have the option of implementing a Ufer ground like what is present at the various facilities where I work. So driving ground rods and proper bonding is a perfectly good way to improve the grounding I have at my house. Kudos to you for apparently having a Ufer ground at your house.
 
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