I have a Sylvania panel rated 125 amps

My problem is our home heating oil tank is old and needs to be replaced.

Both the furnace and the water heater run on oil. And the furnace runs on electricity as well.

Instead of replacing the oil tank, I would like to put in an electric water heater, and get rid of the oil altogether. The furnace runs fine on electricity. And it has its own sub-panel.

My problem is I've already got a grand total of 315 amps on my breaker panel that says 125 amps. 30 for the dryer, 40 for the stove, a 15+15 for a window A/C, and all the usual stuff you'd find in a 3 bedroom bungalow.

There's still room to plug a couple more, but my father in law says adding an electric boiler would place too much load on the panel and cause the whole system to short out.

He wants me to stick with the oil. But I don't think spending $1000 on a new fuel tank is a sound investment. I'd rather put it in a new circuit panel if I have to.

My father in law cays I could put what's called a miser between the stove and the boiler. So they can't both put a load at the same time. He recently did some re-wiring in our kitchen, and added 5 new circuits. One for the microwave we put over the oven, and 4 seperate circuits, one for each of the GFI plugs over the kitchen counters. I thought the 4 plugs could all go on one circuit, but he said they had to be on separate circuits. So we added four 15 amp breakers.

The way I see it, we're not using more load. Just spreading it over a whole bunch more 15 amp circuits that are filling up the panel. I don't see a problem with adding another circuit for a water heater.

I was also thinking of using the existing 30 amp circuit from the window A/C. We never use the AC. I can pull the wire back down to the basement, and use it for a boiler.

And if we go with a miser, can I plug it in a way that the water heater doesn't take priority over the stove? I'd rather the water in the tank cools off a little while the stove is going, than the stove cutting out every time the water temperature dips.

 

Wiring is not a hobby.
Call a qualified electrical contractor.

 

I had a siemens 200A Panel installed in place of my old panel for 600 buckaroos. Electricians need to make a living, and competition for work is fierce, use that fact to your advantage and find a good electrician that will work for a fair price.
I also recommend using a qualified electrician..the previous owner of my house tried doing wiring himself and screwed up the circuits, the wiring was not installed to code and was not safe. I have replaced many lines, and found charred receptacles and severly overloaded circuits because the last owner was not qualified to install these circuits.

I have an oil burner for room heat only...My hot water comes from an electric heater..the water heater has its own electric meter outside and isn't even hooked to the main panel. My electric heater is on a separate meter that automatically shuts off during the daytime when rates are highest, I get a discount from the utility company for that added set-up.

Getting rid of the oil is a great idea too!!! I am with you 100 percent.
What I don't understand is how your furnace will run without oil????
Do you have a heat-pump hybrid?

 

To figure your current load you need to add up the actual appliances not the circuit
breakers!! What is the service coming into the house? your best bet is to add a sub
panel. At least you don't have those blasted federal pacific boxes I worked at a time
share that had those and I had to work those breakers out every month or they would
freeze in place!! The knucklehead who added the perimeter lights just put them all on
one 20 amp circuit and it was up near 32 amps that is a murder rap waiting to happen!!

 

I have a 125 Amp breaker panel, and a 100 Amp sub-panel dedicated to the Electric furnace.

The Electric Company meter says 200 Amps.



That's what I thought too.

We added a bunch of circuits when we remodeled the bath and the kitchen. But we didn't add a lot of lights or anything.

The house was built in 1959. The previous owner put in the 125 amp panel and added a few circuits for the heavy load appliances (dryer, stove, window a/c). But the rest of the wiring stayed as it was.

When I moved in and plugged in a microwave, computer, etc, the whole house would black out every time my girlfriend used the toaster and the microwave at the same time.

Now we have that solved by adding a bunch of circuits to the kitchen. The microwave and each kitchen outlet is on its own circuit.

An electric water heater would add more load. But I've used window A/C's and space heaters in the hot and cold seasons, never had an issue.

 

sounds to me like you want to go all electric?Electric furnace and water heater!IF thats so you really need a 200 amp main box.Not a 125 amp main box with a 100 amp box comming off that!

 

What kind of furnace is this? I've never heard of one that burns oil and also uses electricity to produce heat. What brand is it?

 

I'm a licensed electrician and you can't figure out your panel load by the number and value of the breakers. Most standard houses on average use 30 amps of a 100 amp service. Post the specs of the electric furnance. What is full load current rating of the furnace. This will determine whether your service is large enough to handle the load.

 

The furnace is called an add on plenum heater. It's just a cheap way to convert an old oil furnace to electricity. Uses same forced air system but with a large heating element mounted on the side.

The furnace is 15kW, 240v/60hz

I took some pictures of the circuit panel family.

http://img184.imageshack.us/img184/3038/dscf0390gu2.jpg

The electric meter says 200 amps. Below the main switch is a box called a "demand controller". My father in law called this the sub-panel.

It says 240v/ph
100 amps, 60 CY
controlled stages 2 x 5kW

Demand controller has a large breaker switch in the front and the red wire goes to the electric furnace.

The demand controller has two wires going into the 125 amp main panel mounted directly above.

the house is a 3 bedroom bungalow. I have the usual stuff, electric range, microwave, toaster, fridge, dryer.


My father in law wants to put a load miser on the circuit going to the electric furnace. So the furnace and the water heater cannot both draw a load at the same time. I'm not crazy about that idea. If I"m going to spend money, I'd rather upgrade to a bigger panel that can handle a heat pump, central a/c, and be done with it.

But if I can just plug the water tank on the existing panel that would work out swell

 

> But I don't think spending $1000 on a new fuel tank is a sound investment

Electric is the most expensive way to heat water, except maybe an external propane tank.

Have a qualilfied person come in and see if you can have a 200 amp service installed or a 100 amp sub panel installed. Nothing to fool around with yourself.

Your father is right, too much load. The load (depending on the heater) will run from 30 amp 230v min to 45 amps 230 max for most 40-60 gallon hot water heaters. Pretty much no way to add it to the exisiting 100 amp panel.

The 30 amp water heaters need at least 1 hour to refill a tank, the 45 amp ones need much less.

 

That's an interesting set up. Technically you only have a 100 amp service as the house panel is fed off of your electric furnance controller. You will notice that your house panel doesn't have a main breaker and the panel is being fed by #2 AWG copper, which is rated for 100 amps. A 15 kW furnance will draw about 65 amps. That is kind of tight for the rest of the house off of a 100 amp service. Code stipulates a 200 amp service for all houses heated by electric heat here, I don't know what your code would say you have to install. Your meter says 200 amps because it is rated for that but doesn't necessarily mean that the incoming cables from your utilities is rated for that. Sometime you can tell by looking at the size of the mains that are brought into the meter, but a lot of utilities use their own method for determining how much current their gauge wire can support. If it can support 200 amps, then upgrade to that, however you will have to then run the electric furnance controller off the panel and not the way it is set up right now.

 

Here in the states we use the NEC National Electrical Code Book. That is our electrical bible. You have 4 kitchen ckts on 15amp breakers, NEC says 2 kitchen ckts. on 20amp breakers. The microwave is fine. The water tank will be 30amps 5000watts. Furnace will be most likely 2 50amp ckts. Looks to me like you will need a 200amp service.

 

My father in law came by and removed the cover of the load controller for a closer look.

What he found was the main panel, and the load controller for the furnace, are connected to the main switch separately.

The wire to the main panel only runs thru the load controller box, using the two knockout plugs on the top of the box to travel from the main switch to the main panel.

 

Best way to go is to remove the existing panel, heater controller and the disconnect below the meter. Then reinstall a new panel right below the meter with main breaker. rerun all the wire into the new panel. Use a Square D or which brand you prefer, 30 spaces/40 circuits.

 

Thanks for all your info. But looks like there is not that much load on the main panel, since the furnace is not connected to it.

We put in a 60 gallon hot point on a 30 amp fuse.