I found this old Kenmore electric heater that was probably made in the 1940's or early 1950's in a junk store one day, and $12 later it was mine. These old electric heaters were made before any of today's safety considerations and they can be pretty dangerous, particularly as they age. This heater was made with no on/off switch, no fuse, no thermostat, and no double insulation. Basically to turn it on, you plugged it in, and it would sit there and generate heat, at least until one of its porcelain insulators eventually cracked -- then it could become a metal housing filled with live current, and possibly elecrocute you and/or set your house on fire. Not a good way to begin a cold morning......
My wife and I thought this would look nice in our bathroom, so I decided I would replace the insde parts with the insides from a new ceramic heater. Then we could have the vintage look with modern safety features.
Step 1: Disassembly
It was easy to get to the internals of this heater. All I had to do was remove four screws near the base and one on the upper rear of the heater and the base came off with the insides attached. The heat coils were attached to the base with four rivets. Since I would need the base, I drilled out the four rivets, tossed the old unit with the coils and the cord, and kept the base.
With the heater disassembled, I could now take measurements inside the heater's housing to see how much room I would have to fit the insides of a modern ceramic heater.
Step 2: How to void a warranty
Disassembling the new heater was easy -- only four screws held the front to the back. One screw, however, was a "safety screw," designed to keep people like you and I from getting to the insides. Fortunately I had my trusty "custom safety screw removal tool" (see 2nd photo), which worked like a charm. Yes, maybe I've voided warranties before......
I discarded the front of the ceramic heater housing, but decided to keep the back, since all the main components (fan, ceramic elements, etc.) were attached to it (3rd photo), and this would keep me from having to come up with a means to re-mount all the parts. I eventually trimmed the excess plastic at the top of this housing, since it would get in my way in mounting the heater controls.
My initial plan was to remove the two heater controls and mount them on the front of the Kenmore housing near the bottom, but once I saw how the new heater controls were made, I decided against it. These controls were basically formed into one control unit (4th photo), and were not easily removable. Plus, the thermostat was built into one of the controls, and I really needed it to be above the ceramic elements (aligned with a vent that was built into the rear housing of the ceramic heater). So, I decided to mount these at the top of the Kenmore. Knowing I would need longer wires, I carefully marked the four wires that would have to be cut and spliced with the tape tabs shown in the photo, then I cut them.
With the warrantly now completely and totally voided, I proceded on as if I knew what I was doing......
Step 3: Mounting the controls
Because the top of the Kenmore is curved and the control unit's plastic mount is flat, I had to mark the curve onto the plastic mount and relieve it using a rotary tool with a sanding drum. Photo 2 shows the curve marked on the plastic, and photo 3 shows the plastic after being relieved for the curve. I also had to add a filler to cover a gap molded in the plastic. I used a piece of scrap steel sheet (photo 3) secured with high heat epoxy. A mounting tab molded into the plastic was also trimmed.
Photo 4 shows the test fit of the controls on the top of the Kenmore. I then added the length of wire I would need to the wires I had cut on the control unit (photo 5), and cut a metal cross piece to secure the control to the housing (photo 6). Photo 7 shows the control unit from the inside of the Kenmore.
By the way, I didn't mention this earlier, but I sanded the outside and inside of the old Kenmore at the beginning, and painted the inside with Krylon high heat spray paint.
Step 4: Preparing the ceramic heater
At the top of this platform I inserted two studs with machine screw posts for attaching what remained of the ceramic heater's housing. The platform with the screw posts is shown in photo 1.
Next I drilled holes in the bottom of the plastic housing and attached the ceramic heater assembly to the platform using washers and nuts (photo 2).
I then attached the platform to the Kenmore's base by drilling four holes and using wood screws. While I was at it, I attached three new rubber non-slip self-stcking pads to the base. The screws and pads are shown in photo 3.
In photo 4 you can see that I cut off about an inch of plastic housing at the top of the ceramic heater assembly. This gave me a little extra clearance at the top for the controls that I relocated to the top of the Kenmore housing in an earlier step. The ceramic heater also had a little pilot light that I relocated to the top, fastening it in place with a nylon zip tie.
Photo 5 shows the completed ceramic heater assembly (with wires still dangling) ready for mounting in the Kenmore housing.
Step 5: Final assembly
The final assembly involved inserting the ceramic heater assembly about a third of the way into the Kenmore housing and re-connecting the four wires to the contols that I had marked in an earlier step. Each wire was soldered, then covered with a wire nut, then covered with heat shrink tubing -- sort of an attempt at additional double insulation.
Once each wire was attached, I then gathered all the wires at the side of the ceramic heater assembly and used zip ties to keep them gathered together at the side. I then pushed the ceramic heater assembly fully in place and fastened the base to the Kenmore with the original four screws.
Step 6: Completed!
It is important to mention that if you attempt a similar project, remember to not compromise the ceramic heater's safety systems. Basically what I did with this project was put a modern heater inside an old housing. The only intrusion into the ceramic heater was the removal of the front housing and the relocation of the controls, and I made sure to use wire of the same gauge, same heat resistance, and doubled up on my insulation of the connections.
The cost of this entire project was very reasonable. I spent $12 for the old Kenmore, and bought the ceramic heater for $20 (with free shipping).
Other supplies used were:
- Krylon brown hammered finish spray paint
- Krylon high heat flat black paint
- 14 gauge wire
- heat shrinkable tubing
- wire nuts
- rubber non-slip pads
- nuts, bolts, screws, washers
The tool used included:
- drill & bits
- rotary tool with a cut-off wheel and sanding drum
- wire cutters
- wire strippers
- soldering gun
- small saw (for cutting plastic)
This "new" heater is now installed in the bathroom, replacing an old ugly round gray heater. In the end I was glad I had to mount the controls at the top of the heater instead of at the base on the front. Hey, I'm old and it's nice not having to stoop down all the way to the floor to turn it on & off!