Surge Protector on an oven

[Bama_Electrical]

Got a call today asking to come out and put a surge protector on a customer’s double oven. Customer say’s it’s just a standard 4” metal box behind the oven and it’s 240v. Said he is tired of replacing main boards. Already has a surge protector at the main service. Have any of y’all ever put a surge protector on an oven?

 

[Jraef]

Sounds like the oven mfr is scapegoating their board failures on “surges”.

There is no way these mysterious “surges” could be happening in the wiring going to the oven, so adding a second Type 3 SPD at the breaker is what I would do for them just to alleviate their fears.

But honestly, you may get better results looking at the wiring. A bad neutral connection for the oven could be causing them problems. The only things in the oven using the neutral are the light and the controls. A bad neutral connection could cause floating voltage levels going into the power supply portion of that board and cause it to fail prematurely. If the oven was wired up by a DIYer, appliance installer or cheap handyman, they may have bootlegged the neutral to a ground in the box, because it had been originally holding a 6-50 receptacle, meaning there was no neutral wire run out. They won’t like the fix, because you would have to run new wire out to it. But it is what it is.

 

[readydave8]

Customer recently told me he'll need surge suppress when he buys his new oven, I forget if it was dealer or manufacturer this came from

 

[hbiss]

Customer recently told me he'll need surge suppress when he buys his new oven, I forget if it was dealer or manufacturer this came from

Seems to me that it would be a simple matter to incorporate MOVs in the control board design if they think there's a problem.

-Hal

 

[petersonra]

Seems to me that it would be a simple matter to incorporate MOVs in the control board design if they think there's a problem.

-Hal

Most power supplies have them built in and are actually pretty resistant to common surges. My guess is something else is going on.

 

[JohnE]

Well, Kitchenaid replaced (2) control boards over about 5 years in my double oven before the thing caught on fire causing some significant damage. I doubt the issue is related to lack of surge protection. (Incidentally, the insurance company was going after the manufacturer on this incident)

 

[Jraef]

I had a main board failure on my high tech Frigidaire washer. Looking on line, one guy posted in a video that if you open the top, stick a hair blow dryer into a particular opening pointing toward the main board and run it on low for at least 3 minutes, it would make it run again. I tried it and it worked! Lots of commenters on his YouTube video commented on it working for them too. The main board was almost $200, but I found rebuilt boards for $89. I ordered a rebuilt and after swapping it, went over the old board with a big magnifying glass. Sure enough, it was an easily visible cold solder joint. I hit it with the solder gun and kept that board as a spare, even though I didn’t try it out to see if that worked.

Given that this was prevalent enough to spawn a YouTube video and a bunch of comments saying the trick worked for them, I’m willing to bet this cold solder joint issue is widespread. It’s probably just generally poor QC from whomever is making these boards (mine was from China), but they just blame it on “surges” to avoid responsibility.

 

[petersonra]

I have 40+ year old Kenmore washer and dryer. Can still get parts for them.

 

[ptonsparky]

I have 40+ year old Kenmore washer and dryer. Can still get parts for them.

Dryers are so simple, I will repair mine as needed.
The newer washer on the other hand wrings the clothes so much better the dryer needs to run less. That said, I've already had to replace the control board and parts of it are rusting out. I suspect the dryer will outlast the next washer, 3rd one, as well.

 

[drcampbell]

The newer washer ... wrings the clothes so much better the dryer needs to run less. ...

I hang my laundry on a clothesline and need not concern myself with how much additional wind & solar energy I'm "consuming".

... Sure enough, it was an easily visible cold solder joint. ... just generally poor QC from whomever is making these boards ...

When ROHS was new, there were a lot of complaints that the new lead-free solders produced inferior results. As often as not, it was actually because the production plants switched to the new solders without changing any of their process parameters. RTFI!

 

[retirede]

Dryers are so simple, I will repair mine as needed.
The newer washer on the other hand wrings the clothes so much better the dryer needs to run less. That said, I've already had to replace the control board and parts of it are rusting out. I suspect the dryer will outlast the next washer, 3rd one, as well.

We bought a used pair for $25 when we got married. They were probably 10 years old when we got them. The washer didn’t last long (transmission) but we had that dryer for about 20 years. The base finally rusted out where the motor mounted. Only maintenance in that time was a belt and a couple drum rollers.

 

[Jraef]

Before buying our new fancy Frigidaire W/D combo, we too had an old Kenmore set from the 70s that I had repaired a couple of times. When this new one broke down after only 3 years, my wife was angry about having changed (my fault of course, because being male, everything is). There is something to be said for the reliability of electromechanical timers and relays vs control boards. Control boards probably COULD BE more reliable if someone were to avoid making them as cheaply as possible, but that’s not how the world works any more.

 

[drcampbell]

... Control boards probably COULD BE more reliable if someone were to avoid making them as cheaply as possible, but that’s not how the world works any more.

Of course they could. Look at the reliability of brain boxes in cars or control panels in elevators.

It's a vicious cycle. A lot of people don't have the access to capital, the expertise in mathematics or the attention span to engage in long-term thinking, so they select what's cheap & easy. Big retailers don't care about brand loyalty because they carry a lot of different brands, and because a lot of "different" brands all come from the same factory anyways. Ultimately, manufacturers maximize their total profits by maximizing their short-term profits. The "better mousetrap" concept just isn't applicable any more. (if it ever was)

 

[ritelec]

so adding a second Type 3 SPD at the breaker is what I would do for them just to alleviate their fears.

Would this be in addition to a Type 2 installed in the main painel? I'm looking around and only see single pole devices and power strip type 3 spd's.
Do they make type 3 spd's in a two pole and would the type 3 spd (if made) and oven be wired on to the same two pole breaker?
Thanks

 

[Jraef]

Would this be in addition to a Type 2 installed in the main painel? I'm looking around and only see single pole devices and power strip type 3 spd's.
Do they make type 3 spd's in a two pole and would the type 3 spd (if made) and oven be wired on to the same two pole breaker?
Thanks

Honestly, I don’t know. I only deal with Type 1 SPDs. I personally think Type 3 are a waste of money. I only mentioned it because the OPs customer seemed insistent on having something.

 

[PaulMmn]

Check out the Zero Surge brand surge protectors. They have no MOVs, but use an iron-core inductor to 'absorb' the surge momentarily, then release it into the neutral wire (no contamination of ground). I have no interest in the company, other than being a satisfied customer. I have no war-stories, other than 4 of their plug-in units and no electronics destroyed by surges (but I have heard the units sometimes HUMmmm a bit when storms crackle outside). They also have hard-wire units and open-chassis units for more industrial uses.

 

[ptonsparky]

For me personally, the only damage I can recall of my entire adult life has been to a few GFCI devices. Nothing due to low voltage, high voltage, surges or spikes.

(found table...knock, knock, knock)

 

[synchro]

Check out the Zero Surge brand surge protectors. They have no MOVs, but use an iron-core inductor to 'absorb' the surge momentarily, then release it into the neutral wire (no contamination of ground).

It sounds like this iron core inductor saturates when the volt-seconds applied across it exceed a certain value. When it saturates it would become a low impedance and could then shunt current to the neutral to help clamp the voltage. This might be good for short term surges. But it would be less effective for fast spikes because the current in an inductor is proportional to the integral of the voltage across it. In other words it takes time as well as voltage for the current through it to build up.

 

[PaulMmn]

It sounds like this iron core inductor saturates when the volt-seconds applied across it exceed a certain value. When it saturates it would become a low impedance and could then shunt current to the neutral to help clamp the voltage. This might be good for short term surges. But it would be less effective for fast spikes because the current in an inductor is proportional to the integral of the voltage across it. In other words it takes time as well as voltage for the current through it to build up.

There are capacitors in there as well; their web site has a "here's how it works" section. Although my liking them is based on negative evidence (ie no destroyed electronics in over 20 years), I like the fact that they don't use MOVs (and they have horror stories on their web site).

 

[4x4dually]

Seems to me that it would be a simple matter to incorporate MOVs in the control board design if they think there's a problem.

-Hal

Indeed. Filtering power on the boards would be the smart thing to do; however, I'd just like OEMs to make a standard double oven that has a temp dial and heats up. If they'd drop all this Wi-Fi horse crap they wouldn't need boards that are so susceptible to everything. I'm currently trying to buy appliance for our new house and everything we like has electronic wiz-bang features in them. Just asking for issues. It needs to heat up. That's it. I don't need to turn it on and off from Arkansas. [/rant]