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Old rusty heater resurrected

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I bought an old rusty electric heater at a flea market because I liked its vintage style.  The blower motor was frozen and the heating coils and wiring looked dangerous, but the cabinet was sound, although it had a lot of surface rust inside and out.  This instructable walks through the steps I took resurrecting this old heater.
 
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Step 1: How it all began

I forgot to take a photo of the heater before I began, but from the disassembled cabinet you can see the condition this old heater was in.  The cabinet parts are shown in the first photo, and the heating element/blower assembly in the 2nd photo.  There was a lot of internal and external rust on the cabinet panels, the fan motor was frozen, and the wiring was old and falling apart.  Plus, since these old heaters were made with no safety systems I really didn't want to try and repair the parts that made heat.

Step 2: Materials required

The rebuilding materials were fairly simple.  I bought a new inexpensive electric heater ($24) that had a heating element that would fit within the old cabinet.  I removed the heating assembly and controls from the new heater and saved the empty cabinet for a future instructable (it will become something other than a heater!).

In terms of supplies I used sandpaper, 14 gauge wire, wire nuts, and spray paint.  The tools used were a soldering gun (and solder), drill & bits, screwdrivers, and a metal cutting saw.

Step 3: Dis-assembly & rust removal

Dis assembly was easy -- I removed 24 sheet metal screws and the cabinet (photo 1) and heating assembly (photo 2) were all apart.

The first thing I tackled was to remove the heavy rust from inside the cabinet.  The cabinet's insides are not visible when the cabinet is assembled, but I wanted to stop the rusting.  I aggressively wire brushed the insides of each piece of the cabinet until all loose rust was gone (photo 3).
f.35 months ago
Hey thanks for the quick response even though it is what it is. I like that you give positive forward motion anyways. I have been doing some brainstorming and I think that it might work out with the help of a transformer. I also have the option to hardwire it to a space saver circuit breaker that is free. That gives me 2 120 legs. Just have to make the two halves work together. Anyways I'll be looking forward to seeing your next 'ible. I'm curious as to what you are going to do with the shell of that heater.
knife141 (author)  f.35 months ago
The heater housing became the case for a computer. You can see it here: http://www.instructables.com/id/From-metal-heater-to-computer/

f.35 months ago
Really cool project. I have a project coming up and would love to hear your thoughts on it. It has to do with the same topic, sorta. I am wondering what it would take to put more than one of those heating elements into one chamber. I have three of those newer type heaters that you used to fix up the old one. The idea is to convert a small propane, forced air furnace to run on electric only. I thought that if you could replace the gas burners with a few of the coils it would work in a similar fashion as the propane setup. My hiccup is I'm not sure about what it takes to combine the coils and I would have to also figure out something clever to get it all powered. The amount of electricity to be supplied isn't so much the problem as is how to make coils heat up using 120 and a furnace thermostat and blower unit work (that uses 12v) together. I'm sure that I can figure it out but any thoughts, ideas, or genuine advice would be greatly appreciated.
knife141 (author)  f.35 months ago
I'm not sure I can help -- combining 3 heating elements might require more amps than the 120v line could handle. Of course, just because I don't know how to do it doesn't mean there's not a way. This might be a good question to post on the "answers" section of the site. Good luck with your project!
Ed-win2 years ago
Should you have used a junction box instead of soldering the connections? Very nice job! Where can I find out about your electric bicycles? I like the way you think.
knife141 (author)  Ed-win2 years ago
The original connections for the new heater were twisted and held together with a wire nut. I used similar wire nuts, however I always solder my connections in addition to the wire nuts. Junction boxes are used inside house walls and attics to protect combustible surfaces from sparks. No need to use one inside a metal cabinet. As for my electric bicycles, I never made an instructable on building them, however I did make one for an electric scooter I built. You can view it here:

http://www.instructables.com/id/Electric-Scooter-pushed-by-monkey/

Thanks for your comment.
tim_n2 years ago
How did you earth the metal cage?
knife141 (author)  tim_n2 years ago
The new heater that was used in this was a double-insulated design, so grounding the metal housing was unnecessary.
snayl2 years ago
Very cool, well documented, loved the attention to safety and clean work. You *are* a pro!
knife141 (author)  snayl2 years ago
Thanks for the nice comment.
atlantica2 years ago
and where does one procure phosphatizant/phosphoric acid?
knife141 (author)  atlantica2 years ago
Don't know where you live, but a google search for "phosphoric acid" will turn up many places to purchase it -- from building supply stores to swimming pool supply stores.
Ill give it a try thanks. I've never seen it in stores, but that doesn't mean it isnt there.
slaitch2 years ago
I know you said you're already making plans for this nifty metal box right here, but might I add that my first impulse towards that cabinet is guitar amp.
knife141 (author)  slaitch2 years ago
A guitar amp is a good idea, but probably not for me since I don't have the skill to play. But, I am indeed thinking of something electronic. Thanks for the comment.
rimar20002 years ago
What a good work! I use phophatizant liquid, successfully.

If you don't know it, please read my comments here.
knife141 (author)  rimar20002 years ago
Thanks, Osvaldo! I googled phophatizant and as best I can tell it means phosphoric acid, or at least a diluted form of the acid. Is this correct? Thanks for your comment and the information!
knife141 (author)  knife1412 years ago
Oops! I replied before I read your comments. It is indeed phosphoric acid. I'll give it a try the next time I'm dealing with a lot of rust!
I love phosphatizant!
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