Old house, old wiring w/ four 15 amp circuits: Can I install kitchen track lights w/ 4 or 5 heads w/ 50 watt bulbs each? Or blown fuses in our future? Of Course, can’t use toaster at same time? How many wattts will 15 amp fuse support? I’m new to this stuff, thanks for advice.
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Your new lights would pull about 2.1 amps. Cant tell you if you should do this or not because I dont know what else is on your circuit. Time to rewire methinks.
"How many watts will 15 amp fuse support"?
use Ohms law. P(power in watts)=I(amps)x E(volts). You said you only have 4 15 amp fuses. Is that all in the whole house or did you mean that's all that's available? If the whole house only has 60 amp service I'd upgrade the service before doing any other electrical work. I'd also take a look at the exsisting wiring and outlets to be sure they're safe. I.E. aluminum wire, cracked outlets, light switches that operate smoothly.
Harry's Homeworks
Rhode Island
A 15A fuse at 120 volts will support up to 1800 watts, though by Code should not be loaded more than 80%, or 1440 watts. That is the over-simplified answer. There is more to it that that.
As far as wether or not you will blow fuses, etc., depends on what all is connected to the circuit.
My last house had old wiring and a 60A service and if you ran the vacuum while the microwave was running, would pop the breaker. Had an AC installed along with a new 200A service and panel. You might want to look into the new service, you need it, and it will help in the resale of your home.
Thanks, guys. I know, I know, rewire/upgrade is due. But for this retiree on fixed income, etc...I've asked a couple of pros to look and give opinions on rewire, and estimates, and they would not commit:Don't know what they would run into, etc so would only take the job on hourly basis. Kind of scared me, such an open ended, sky's the limit deal. Tim, out of curiosity, what did your rewire job cost? Anyone else out there have rewires done to an old house and the costs?? Thanks.
I had a 1950s house like that done in South Dakota a few years ago, in order to add central AC. Because the house was only 800 square ft. we went to 100 amps IIRC.
The electrician ran a new service from the meter, put in the panel, wired the AC and furnace, and connected several "new" circuits that I pulled the wire for.
I think the bill was $1200-1300.
In that old house, it was pretty easy to use the old wires to pull some new circuits, and correct a couple of hack jobs perpetrated by previous owners.
In the end, he left all the old circuits in the fuse panel and used it as a junction box. Added the new panel next to the old one, and ran the new circuits directly to the new breaker box.
K
Prices vary, of course, from area to area - upgrade to 100 A box in my area is about $1000. To 150 A about 1,200.
That is just upgrading the service, meter base and panel and using rexisting circuits. Adding circuits is one thing. In my area few houses are actually fully rewired. Existing circuits stay, new circuits added as needed.
_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
Just did a new service box 100 amp and 60amp sub panel in garage on a 1100 sq ft house build in early 50's. This included rewire of the garage and a 300 sq foot room with new circuits. it was $2000. I was told it was a deal for my area, and I am sure it was since a ex brother inlaw did it for me. He spent with a helper almost three days getting everything done.
Paul,
I need to clarify a little. I had the old panel (and the subpanel) replaced with a new 200A panel, old wires reconnected to the new panel. Subsequent rewiring was by owner (me). Since the service drop was overhead, the utility provided a new drop at no charge. The cost of replacing the panel and reconnecting the existing circuits, plus new circuits for the furnace and condenser, was buried in the cost of the new furnace and AC that was installed, but as I recall, added approximately $500 to the job, which was very reasonable.
Tim
If you can't afford to do the whole house at once, how about doing it in stages? Replace the service first, with a new 200 amp service. Then do the rest of the house when you have the money.I used to work in a fire hydrant factory. You couldn't park anywhere near the place.
Thanks for all the input and advice. Guess it's time to bite the bullet and consult a local pro. Boss' suggestion to at least do a new service panel and add some new circuits,would be a good beginning, esp for the kitch and dining circuits. (it's not good when the lights dim whenever the frig goes on, is it?). Thanks again, all. Paul
what part of town do you live paulz.
4lorn where do you pick up a module like that. and how do you find time while reading and answering all of these posts
The delay on/off module is from an old commercial air conditioning unit but should be available new at a AC supply house.
Time to read and answer. Insomnia.
FWIW, by replacing the 1949 fuse boxes with a new 200A service, my homeowners insurance dropped about $40/yr. And I sleep much better at night. As for the cost, I have outlets in my house that cost $10 and others that cost $150. If someone bids a job for a total cost, you can bet they are pricing their expected hourly rate under a worst case scenario. While open ended, I bet the hourly people will be cheaper in the long run. Ask around to see who has had work done recently and would they hire that person back again. Word of mouth is the best guarantee. In fact, I like my guys so much, I won't recommend them to people who might not treat them fairly, as i want to remain on their good side in case i need them to do more work.
Thanks for the info, Wood, Reading is on my agenda for these frigid days and nites! Rewire after the spring thaw. Paul
Will it handle it. As a quick check, and for many other uses, I keep a blowdrier on my truck. With a selection of something like 400/600/1200 watts it makes a great trouble shooting tool and handy dummy load. If the customer wants to install a few lights I could amp the circuit but it is far easier to plug in a blow drier.
For this job I would set it on low and plug it into the intended circuit. Adjust other loads on the circuit to simulate normal usage and see if the added load blows. A ten minute run is usually sufficient to check but a longer run won't hurt.
Note: This will also expose weak connections or other problems so use a little common sense. A worn receptacle will tend to overheat with the added load but hey it needed replacing anyway.
I have been known to plug the blow drier into an AC on/off delay module so that the blow drier turns off and on every five seconds. Makes a handy way of finding a circuit when the signal injection model fails or isn't handy. Also it tends to make weak connections buzz. Makes them easy to find walking around.
paulz,
What's on the circuit now? You can figure this out very simply.
Add up the watts of the stuff on the circuit that you might possibly use at the same time, and divide by 120 to get amps; or if the appliance nameplate gives amps, just add that in.
If the total amps on the circuit that you want to add the lights to is less than 15 (with the new lights added in), you're OK. There's no Code requirement to derate 25 percent (to 12 amps) in a residence, because the loads in a house are considered to be "non-continuous" (not on for three hours or more at a time). So no cushion is required (although it's not a bad idea).
It's not unusual at all for "old work" like your job to be bid on a time and materials basis. You just don't know what kind of problem you might run into, when you start running wires in finished walls.
If the circuit won't handle the additional load, and the fusebox is full, you could have the service panel replaced/upgraded. As a starting point, figure $100 an amp. ($1500 for a 150 amp). Then you'd have spaces for a couple of new circuits. Running those would be additional, and cost depends on the difficulty of running the wire. This depends on the house--is there a full basement and walkable attic, are walls sheetrock or drywall, and so on.
You ought to get one of the DIY books on electrical; Sunset, Black and Decker, and Ortho all publish good ones, and they're usually available in the public library.
Good luck,
Cliff
I think the "creative homeowner series" book on home wiring is the best of the bunch. A step up from there is Mullins book on house wiring with the NEC. The more educated you are, the less likely you are to get taken, and the more likely you are to get what you want in the end.