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Anyone convert a cast-iron radiator to electric?

This may be crazy, but hear me out. I am thinking (constantly, it seems) about different options for heating a new bathroom in an old house that currently uses steam heat everywhere else.

Adding steam to that new room won't be easy, so now I'm thinking about something electric. I'd love to have the look of the old cast iron radiator, but an electric system. My thought is to buy a salvaged cast-iron radiator, plug the air vent, fill the radiator with water and then on the inlet port, fit a hot water heater element (the ceramic insulated type), that is attached to a thermostat. This would give me the *look* of the old radiator without incurring the trouble of steam.

I know there are oil-filled radiators at Walmart, etc. but I don't want the modern look of all the controls on the side. I think my idea would be pretty stealth, especially if I used some cast iron pipe as the "conduit" for the wire.

What do people think? Feasible?

Comments

  • bigugh_4
    bigugh_4 Member Posts: 406
    You have an idea!

    but do not build yourself a steam bomb! I do not know the parameters of the wal-mart electric oil filled radiators, but be very careful with your idea. The biggest explosions in this world have been steam related. Volcanoes! and water. BOOM! not funny. It does sound feasible though. good luck
  • John@Reliable_5
    John@Reliable_5 Member Posts: 76
    Mmmmmmmmm,Sounds easy but..........

    you would need pressure relief valve, hi limit safety, and operating control so much for the look of old! Maybe a better way if floor isn't down yet would be a electrical mat under a tile floor is one way.John@Reliable
  • Art Pittaway
    Art Pittaway Member Posts: 230
    BigUgh is almost right, but

    as long as the radiator is fitted with a low pressure relief it can only turn your bath into a steam room. The massive waterheater explosions depend on water volume, the drop in pressure and a temp of 300F to make it work. What you want will be below 212F and only 2 - 3 gal of water. You will need a sufficient electrical supply to power a heating element that is sized to provide the rooms heat. The radiator should have a setpoint control for max temp. limit wired in series with a thermostat for room control, 24v for safety. Anything is possible but maybe if you used a small under counter electric (5 gal) water heater, pump, expansion tank and controls you could have it with out building from scratch, and it's UL listed. Provided code will permit in your area. The key is know your electric and if in doubt get help, bathrooms are no place for an electrical problem. Just some thoughts.
  • Steamhead
    Steamhead Member Posts: 16,796
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Why not buy an oil filled radiator, find out what kind of oil is

    in it and fill you rad with it, then take the guts of the oil filled radiator and install them into the old rad.
    You would have all the controls and safety items designed to the application.

    Let us know how it turns out.
  • nick z.
    nick z. Member Posts: 157
    For expansion,

    don't let the rad. fill all the way with water, the air pocket in the top will act like a expansion tank.
  • Joe C
    Joe C Member Posts: 10
    Home-brew rad

    Just remember what your insurance co. WILL say if God forbid something should go wrong " NOT UL listed NOT COVERED".Otherwise, interesting idea.
  • Jonathan_2
    Jonathan_2 Member Posts: 5


    Art wrote:

    "As long as the radiator is fitted with a low pressure relief it can only turn your bath into a steam room...You will need a sufficient electrical supply to power a heating element that is sized to provide the rooms heat. The radiator should have a setpoint control for max temp. limit wired in series with a thermostat for room control, 24v for safety."

    This is exactly what I was thinking. An element that shuts off when the liquid in the radiator reaches 170ºF, wired in series with the room thermostat. I wire similar systems all the time at work for radiant elements (industrial radiant heaters, not HVACs) and the system I've described is very similar. The low pressure relief is a good idea--I will do that. I'll also leave an air pocket at the top for expansion and I may mix a bit of antifreeze in as well to keep the boiling point up and corrosion down. I'll post some pics if and when I get it worked out.


  • Joe_13
    Joe_13 Member Posts: 201
    Hot water Rad

    If you're not using the tankless coil already, put one in and create a hot water zone that would be easier to pipe up to the bathroom. A bit much, but a proven, safe way to do it.
  • Arthur
    Arthur Member Posts: 216
    Electric radaitors

    We use to do them years ago.
    Stick an element in the bottom and fill it with transformer oil (go talk to a friendly power board guy and for a doxen he will probably get you a couple gallons of use stuff). We used to fill the rad almost right up to the top (stand it on end) and put it on all night with out the plug in,and then cover with several old sacks, The switch on and leave all night. top up the last little bit the next morning and leave for 1/2 hr then seal the plug in while its hot. Watch the oil will be hot and can burn so make sure it doesn't fall over when you're working on it.
    Things to watch for 1) make sure the plug is SEALED. otherwise it can leak and suck air when cold. 2) Watch for the spilt oil, don't over fill it leave about a pint from the top and then top up the next morning.3) pays to do this out in the shed can be a bit messy.
    Good luck.
  • Earthfire
    Earthfire Member Posts: 543
    Used transformer oil

    and now the current owners can sue the power company for PCB contamination of their house. Electrical experimentation in the bathroom should not be done. Electric current and water DO NOT mix. Besides if you do enclose the element connections, the box hanging on the rad will not give you the effect you want. I would suggest running a hot water loop of the boiler to feed the rad if a steam connection is not feasable. Use Pex and run the heat lines in the same chase that you are bringing in the water lines thru.
  • Arthur
    Arthur Member Posts: 216
    Used Transformer oil

    I didn't suggest he tips the oil all over his bathroom I did suggest he do it in the garage or shed. And provided the plug seals there will never be any oil in the bathroom. If you're that worried about the used stuff then get some new oil then without the pcb in it.
    We did quite a few years ago and never had a problem, Only once the apprentice over tighten the plug and cracked the CI rad, We used to run them from a room stat. And if wired properly (profesionly) there won't be any problem in a bathroom. After all towel rails are allowed in Bathroom (were else would you expect to have towels).
    As I said we never had a problem main thing is to make sure it doesn't suck air when cold as then it will build up pressure when hot.
    Pex pipe is not rated for use on steam. Only hot water up to a maximum of 80c + NOT steam.
  • Craig Krauss
    Craig Krauss Member Posts: 4


    Burnham made these years ago. A cast iron radiator with an electric water heater element. I have one stored in my garage. It still worked when I pluged it in about 8 years ago.
  • Earthfire
    Earthfire Member Posts: 543
    I wrote

    hot water loop not steam line when I suggested pex
  • R. Newton
    R. Newton Member Posts: 4
    Water Radiator on Steam System

    Johnathan:

    It's easy enough to pipe below-the-waterline hot water to a radiator on an otherwise steam system, provided the radiator is not too high above the boiler (about 2-1/2 stories is max.) Dan Holohan published an article about it in 1991 and it's probably in one of his books. If interested contact me and I will send you a copy. This would be the safest/easiest way to go without electrical or oil worries.

    Reece
  • Dale
    Dale Member Posts: 1,317
    Don't use water

    You can put and element in the bottom , one made to heat in air, and just heat up the iron. Check Grainger for what will fit into the bottom nipple connections. I would drill some small holes in the top just in case and I would make sure it was on a gfi circuit.
  • GEO_3
    GEO_3 Member Posts: 67


    Check the site, Anarchist's Cookbook, How to build a bomb.
  • TomTerrific
    TomTerrific Member Posts: 3
    How about diathermic oil?

    I was thinking about extending a new electric radiator filled with diathermic oil by just creating a hole with a fitting and pumping it through pipes for radiant floor heating where I use the heater as a reservoir. Similarly, you might be able to pipe in a new one to an old one and keep the new one out of sight? Just a thought
  • TomTerrific
    TomTerrific Member Posts: 3
    How about diathermic oil?

    I was thinking about extending a new electric radiator filled with diathermic oil by just creating a hole with a fitting and pumping it through pipes for radiant floor heating where I use the heater as a reservoir. Similarly, you might be able to pipe in a new one to an old one and keep the new one out of sight? Just a thought
  • TomTerrific
    TomTerrific Member Posts: 3
    How about diathermic oil?

    I was thinking about extending a new electric radiator filled with diathermic oil by just creating a hole with a fitting and pumping it through pipes for radiant floor heating where I use the heater as a reservoir. Similarly, you might be able to pipe in a new one to an old one and keep the new one out of sight? Just a thought
  • cwhit1
    cwhit1 Member Posts: 2
    retired ford worker

    There's a Canadian company Ben doing this a long time. Thay convert hot water to electric. Thay take salvage cast lorn radiators and put some kind of heating element in them. Check em out. Www.ecorad.CA
    Patclou
  • cwhit1
    cwhit1 Member Posts: 2
    retired ford worker

    There's a Canadian company Ben doing this a long time. Thay convert hot water to electric. Thay take salvage cast lorn radiators and put some kind of heating element in them. Check em out. Www.ecorad.CA
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,318
    Burnham made these

    I saw one in New Bedford mass that the owner got with their house as an answer for a cold room. Of course after I fixed the piping issue that was 100 years wrong the heater was not needed.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
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