The Dean of Home Renovation & Repair Advice

COMMUNITY FORUM

camdvm

04:08PM | 03/16/07
Member Since: 10/17/05
21 lifetime posts
Bvelectrical
Hi, and thanks for reading my message:

We have an electric forced air furance on a 125A breaker. Our panel is 220A. I notice when the furance first comes on, and also randomly when it is running, its beaker in the panel "humms". If I press against it, the humming stops. It does not feel hot, and the panel doesn't seem hot. The breaker is probably almost 18 years old, and we have just recently noticed this sound. The furance works 100% normally. Any ideas why the breaker is humming? As well, which I consider normal, when the furnance first comes on - the house lights dimm for 1s. This is normal - I assume? Thank you.

TimBonham

08:35PM | 03/16/07
Member Since: 01/09/07
197 lifetime posts
Most likely, it's humming because it is vibrating. (You should be able to feel this if you touch it lightly.) If it is vibrating, that's probably because it's loose.

You could attempt this to fix that:

1. Turn main panel breakers off.

2. Check again that they really are off.

3. Remove the furnace breaker from panel (leave the wires connected to it).

4. On the bottom of the breaker, there will be little metal brackets that hold the breaker onto the live bars in the panel. Using a pliers, _gently_ squeeze them a bit tighter.

5. Re-install the breaker into the panel. Is it tight now? If not, remove it and squeeze it a bit more.

6. Turn power back on.

This might be enough to take care of the problem, and it's a cheap & easy solution.

If it doesn't, then the humming may be from inside the breaker. So then you either have to spend the money to replace that breaker now, or just live with the humming until the breaker fails (which might be never, or might be next month, and on a cold night, after the stores have closed, leaving you with no heat).

Billhart

05:06AM | 03/17/07
Member Since: 04/25/05
1918 lifetime posts
In addtion to what Tom said I believe that electrical furnaces are limited to 60 amps per bank of elements and that a larger one would require several sets of breakers 60 amps or less.

But I don't have time to research the codes.

Are you sure that breaker feeds the furnace or does it feed a sub-panel that feeds the furance?


Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply_choose_button

captcha
type the code from the image

Anonymous

Post_new_button or Login_button
Register

Follow Us

horizontal divider
facebook
 
webapp1