Under-performing circuit panel with two 240V appliances
#1
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I have an electrical problem that's driving me nuts.
I have only two appliances that require 240V lines in a small Cabin in the woods. Both appliances, as well as all other electrical outlets and switches, were working fine just a few days ago. I showed up the other day, turn the circuit panel main breaker on (as I normally turn it off when leaving the cabin), turn the breakers on to the 240V appliances (a water heater and a range), and neither one works.
Each appliance is connected using a single 10-gauge line to a 240V, 50 amp breaker respectively. The lines are easy to follow under the cabin and I verified that they are in good condition and independent. I even replaced the water heater breaker with a spare 240V 40 amp one to no avail. I further changed the position of the breakers to make sure; heck, I even took ALL breakers out of the panel and left exclusively the water heater on, and still no go.
This is a simple configuration on a 8-year-old, 150 amp panel with relatively few breakers attached, namely the above two appliances (2 50-amps), bedroom lights, living room lights, kitchen lights/refrigerator, and outside lights (all 15 amps), and a 20 amp water pump breaker. That's it!
I witnessed three issues that were completely illogical to me:
My questions are as follows:
Thank you!
Rodrigo
I have only two appliances that require 240V lines in a small Cabin in the woods. Both appliances, as well as all other electrical outlets and switches, were working fine just a few days ago. I showed up the other day, turn the circuit panel main breaker on (as I normally turn it off when leaving the cabin), turn the breakers on to the 240V appliances (a water heater and a range), and neither one works.
Each appliance is connected using a single 10-gauge line to a 240V, 50 amp breaker respectively. The lines are easy to follow under the cabin and I verified that they are in good condition and independent. I even replaced the water heater breaker with a spare 240V 40 amp one to no avail. I further changed the position of the breakers to make sure; heck, I even took ALL breakers out of the panel and left exclusively the water heater on, and still no go.
This is a simple configuration on a 8-year-old, 150 amp panel with relatively few breakers attached, namely the above two appliances (2 50-amps), bedroom lights, living room lights, kitchen lights/refrigerator, and outside lights (all 15 amps), and a 20 amp water pump breaker. That's it!
I witnessed three issues that were completely illogical to me:
- Both 240V appliances were receiving some current because the oven's small LED light would turn on red when turning the oven on, but the heating elements or the top stove would not work or heat up at all.
- The water heater green, stand-by LED would ONLY turn itself on when the kitchen light was turned on. Remember, I verified about 5 times that the water heater had its own, independent circuit to the panel; there was absolutely no reason whatsoever why this was happening. Upon disconnecting the kitchen 15 amp breaker from the panel, the water heater green LED would no longer turn itself on (of course). However, there was still some current being received by the water heater because I tested it. Unfortunately, I did not have a multimeter with me, but being resourceful, I stripped the wires off an old bulb socket, and proceeded to verify that each hot on the water heater was getting some electricity. However, one wire was providing intense light (as you would expect), but the other one was outputting a very dim light. So obviously, the appliance as not getting the entire 240V current to make it work, although I cannot say what the exact voltage reading was until I return with a multimeter.
- Finally, the kitchen breaker was also under-performing, that is, the kitchen light was flickering and the small fridge would turn itself on for just a few seconds. When I moved the kitchen breaker to a different location within the panel, the problem disappeared, that is, the fridge began working just fine, and the lights were at full strength. What's even weirder is that when the breaker was in its new position, the water heater LED would NO longer turn itself on when turning the kitchen light.
My questions are as follows:
- Why would the 240V appliances not be receiving enough juice? If all other lights and small appliances work fine, why not these two in particular?
- How in the world did the kitchen lights turn the water heater LED light on if they have completely independent circuits?
- Is it possible at all at the circuit breaker panel be damaged? That is, could it be that the panel itself be transferring electricity from one breaker slot (kitchen) to the other (water heater), hence enabling the kitchen to send some electricity to the water heater via the panel?
- Am I seeing ghosts?
Thank you!
Rodrigo

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Thanks for you reply CasualJoe. Do you mean that the issue may be coming from outside the cabin? Should the power company be at fault?
Also, is leaving the power on on my circuit panel dangerous?
Also, is leaving the power on on my circuit panel dangerous?
#4
You need to call now and leave the breakers off till it is checked. Excessive voltage on one leg could damage things. As Joe wrote call the emergency number. Do not call customer service.
#5
The #10 should not be on a 50 amp breaker.it needs a 30 amp maximum. This can be changed after you get the power issue fixed.
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Thank you all for your advise. Unfortunately, I am not at the cabin at the moment and will not be able to get there until the morning.
I believe it behooves me to be physically present when the POCO technician gets there, correct?
POCOs are known for washing their hands and assuming that issues are cause after the panels. What should I look for when they are verifying for this?
Thanks again, and yes, I will replace the breaker to a 30 amp.
I believe it behooves me to be physically present when the POCO technician gets there, correct?
POCOs are known for washing their hands and assuming that issues are cause after the panels. What should I look for when they are verifying for this?
Thanks again, and yes, I will replace the breaker to a 30 amp.
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Quick update: I actually went up to the Cabin with an electrician friend of mine. As it turns out, there is full electrical current coming from the POCO drop. However, the left side of the panel is not getting enough voltage. It could be the main breaker, but I may as well replace the circuit panel (150 amp) and the main breaker. This is a safe fix.
Could anyone suggest otherwise?
Also, I was wrong. The circuit going to the WH is actually a #6, but according to the WH specs, I should have a 60amp breaker (instead of the current 50 amp), specially when drawing cold water from an underground cistern, as the WH may pull up to 54 amps to heat up cold H2O. I may as well upgrade it also.
I'll keep you posted when we replace the panel.
Could anyone suggest otherwise?
Also, I was wrong. The circuit going to the WH is actually a #6, but according to the WH specs, I should have a 60amp breaker (instead of the current 50 amp), specially when drawing cold water from an underground cistern, as the WH may pull up to 54 amps to heat up cold H2O. I may as well upgrade it also.
I'll keep you posted when we replace the panel.
#8
As it turns out, there is full electrical current coming from the POCO drop. However, the left side of the panel is not getting enough voltage. It could be the main breaker, but I may as well replace the circuit panel (150 amp) and the main breaker.
Also, is leaving the power on on my circuit panel dangerous?
#9
I'm not sure what "the left side of the panel is not getting enough voltage" means, but the symptoms you initially described could be caused by a faulty main breaker. It is unusual to fail in an 8 year old panel unless there was a corrosion problem, but possible sure. The only reason you would need to change out the entire panel instead of just the main breaker would be if there is corrosion or heat/arc damage on the bus bars or lugs. That's a lot of work and expense compared to just swapping the breaker.
The water heater should have a breaker sized consistent with the manufacturer's recommendation; usually marked max OCPD on the label or installation manual. A typical residential tank water heater should have a 30A breaker with #10 wire; however many different styles exist.
The water heater should have a breaker sized consistent with the manufacturer's recommendation; usually marked max OCPD on the label or installation manual. A typical residential tank water heater should have a 30A breaker with #10 wire; however many different styles exist.
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ibpooks, you are right. Replacing the breaker could be it. I did not see any corrosion on the panel itself, but there were some bug nests and other dust and debris, as the panel is under a roof but outside the cabin. I was told it was 8 years old, but I wasn't there at the time. So as CasualJoe mentions, it can't hurt to start anew with my own installs, and having a new panel can't hurt going forward. It will run me about $120.
Just to clarify, this is a tankless WH (Rheem RETE 13, to be precise), so it uses quite a bit more juice than conventional electric WH, especially during winter months as it requires more amps to heat up cold water.
I agree that leaving the main power (breaker) off when not in use is a good idea. I usually do.
Thanks a bunch. I should be able to report back later this afternoon.
Just to clarify, this is a tankless WH (Rheem RETE 13, to be precise), so it uses quite a bit more juice than conventional electric WH, especially during winter months as it requires more amps to heat up cold water.
I agree that leaving the main power (breaker) off when not in use is a good idea. I usually do.
Thanks a bunch. I should be able to report back later this afternoon.
#11
You may be able to swap the panel guts and save yourself some time. It might be spider nests under the breaker.
Ben, I took it to mean one of the legs was not functioning as designed.
Ben, I took it to mean one of the legs was not functioning as designed.
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OK, I just want to resolve this post. There was indeed evidence of charred buses on the left leg of the panel. Was that what was causing the problem? I'll never know, but this is a new start, and since I am not always there and other people may use the Cabin from time to time, I prefer to take no chances. The whole thing cost me about $160 with new breakers, and all is working well at the moment, including the 240V appliances.
Thank you all for your wonderful suggestions and guidance. I hope this experience helps other folks.
Rodrigo
PS, I meant the left leg of the panel, Ben. Sorry, my terminology is definitely not appropriate. Learning something every day.
Thank you all for your wonderful suggestions and guidance. I hope this experience helps other folks.
Rodrigo
PS, I meant the left leg of the panel, Ben. Sorry, my terminology is definitely not appropriate. Learning something every day.
#13
Not a problem. With the visible charring on the bus bar, panel replacement was the best thing to do. Could have been the cause or the effect -- doesn't really matter once it's done. Glad it's up and working now.