Post #1412: A simple heated outdoor faucet (tap, spigot, sillcock, hose bib) cover.

Posted on January 25, 2022

 

This post shows you how to take a few off-the-shelf parts from your local hardware store and make a plug-in heated cover for an outdoor faucet.   This will take you about two minutes to assemble, and, depending on how much heat you think you need, will cost you either about $6 (using a cheap night-light), up to maybe $17 (using a proper candelabra-base light fitting), including some spare light bulbs.  The only tool you need is a knife.

It’s not rocket science:  Add a candelabra-bulb socket or a cheap night-light to a standard foam faucet cover.  Screw in a night-light or similar incandescent bulb.  Attach that foam faucet cover to the faucet, and snug it up against the wall.  Plug it in.  Turn it on.  You’re done.

The only value added I’m bringing to this, other than pointing out the obvious, is that I’ve tried three wattages and recorded the results.  Having tested it, you can be assured that you’re not going to end up with a flaming piece of Styrofoam attached to your house.  In fact, the 4 watt bulb is barely warm to the touch.

Pick the wattage that meets your needs:

  • 15 watt incandescent:  60+ degrees F over ambient temperature
  • 7 watt incandescent: 40 degrees F over ambient temperature
  • 4 watt incandescent: 28 degrees F over ambient temperature.

E.g., if I’m expecting a low of 6 F in my neighborhood, a four watt bulb should keep the inside of that foam cover at a toasty (6 + 28 =) 34F.  These temperature increases were measured with the Home Depot foam cover (referenced below) snugged up against a brick wall.  You might get somewhat better or worse results depending on your siding (e.g., wood or aluminum).

The only warning is that you must use an old-fashioned incandescent bulb.  You’re using them for the waste heat, not for the light.  Do not use an LED night-light bulb.  They won’t put out enough heat.  I think that seven-watt incandescent night-light bulbs are available at every hardware store in the country.

The nicest thing about this setup is that is starts with a standard foam faucet cover.  I put these on my faucets at the start of winter, with the cord bundled up, out of the way.  Most of the winter, they just sit on the faucets like a normal foam faucet covers.  When extreme low temperatures are predicted, I unroll the cord and plug them in.  At that point, they’re heated faucet covers.

If you just want some ideas for a temporary fix, to be used for a few days in an emergency situation, read the “Cobbling something up” section below, in addition to the main post.


Parts, tools, and assembly, high-wattage model.

Parts, left to right:

Home depot reference: , $4.

 

Pick one:

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Ace hardware typical reference., $6 for four.

 

Home depot reference, $7.  (Edit 1/12/2024:  I see HD no longer carries these in stores, but Lowes (reference Lowes.com) has the equivalent for $8. 

If you can’t find this part, and a night-light won’t do (next section), see the section “Cobbling something up” below).

Instructions:  Use the serrated knife to cut a small (1/8″ wide) notch in the bottom of the Styrofoam faucet protector.  Bend the metal fitting that comes with the candelabra socket to spread it out a bit.  Press the cord for the candelabra socket into that notch.  Snug the bottom of the socket up against the foam.  Screw in the bulb.

What you see below is the inside of the faucet protector, fully assembled and lit.  Attach this to your faucet, and draw it up firmly against the wall.

One clear drawback is the need to run an extension cord out to the faucet cover.  But, with a power draw so low, the cheapest, flimsiest outdoor extension cord will do.  Optionally, wrap any junctions (e.g., where the extension cord and lamp cord meet, or where the switch is on the lamp cord) with electrician’s tape or other waterproofing material, depending on how exposed they are.

I call this the high-wattage model because that $7 light fixture from Home Depot can easily handle a 15-watt bulb.  And the feet on the fitting keep that bulb well away from the Styrofoam.  But that’s also the most expensive part.  And you need to buy bulbs separately.

There is a cheaper way, if you don’t need 15 watts of heat.  Below.


Much cheaper, low-wattage model:  Use a night-light.

In the original version, I went with a candelabra base fitting because I thought I might need 15 watts of heating.  Turns out, 15 watts was overkill, for me.  And so, you can make this cheaper by substituting a night light for the candelabra base, as long as you keep the wattage down.

The instructions are identical to those above, you just cut a wider notch into the faucet protector.  Take the plastic shade off the night-light.  Stuff the night-light fitting into into place.  (See pictures below).  You’re done.

Originally, I cut back the foam a bit, to clear the bulb.  Not a bad idea, but not really necessary.  A four-watt night light bulb barely gets warm to the touch.

In any case, because the night-lights come with bulbs, you can make this for about $6.  I used a manual night-light, with an on-off switch.  You can use an automatic one, just tape over the sensor so the night-light thinks it’s in the dark.

I would NOT put a 15-watt bulb in one of those ultra-cheapo night light fixtures.  There ain’t a lot of metal in them.  Most of the night-lights I’ve found were rated for seven watts.  One (by GE) was only rated for four watts.  In any case, don’t exceed the rated wattage of the night-light fitting.

Note:  There are heavy-duty 15-watt night lights, sold as plug-in wax warmers or plug-in fragrance warmers.  I have no idea how hard it would be to tear one down to just the socket and switch, for use as an outdoor faucet warmer.  And they cost as much as the high-wattage fitting used in the first section above.  So may guess is, if you’re going to the night-light route, stick with a cheap night light, and low wattage.

Be sure you are getting a night-light that uses an old-fashioned incandescent bulb.  Do not try this with an LED night light.  They don’t generate enough heat.

One final caveat:  Your night light might be rated for seven watts, but that doesn’t mean it comes with a seven-watt bulb.  Here’s a $1.33 model from Menards that specifically says 7 watts for the included bulb (reference).  Here’s a Home Depot reference, 2 for $2.50, rated for 7 watts, definitely sold with 4 watt bulbs.  (reference).

So, if you go this route, pay attention to the bulb.  Otherwise, if you need 7 watts of heat, but ended up with 4 watt bulbs, you’re going to pay more for replacement bulbs than the night-light cost.

 


Cobbling something up:  A few suggestions if you are desperate and need a temporary fix.

The whole point of using these candelabra-base night-light-sized bulbs is that they’ll fit easily into a standard foam faucet cover, with room to spare.  This gives you a good chance of buying a few parts off the shelf and having it fit  your particular faucet, and gives you something you can leave up all winter.

But suppose you’re in a hurry, and just need a temporary fix, and you can’t lay your hands on the parts that I used.  What are some plausible alternatives?   It’s not like light bulb + insulation is somehow difficult to achieve.

I have to warn you that I haven’t tried all of these.  But based on making the ones above, these seem to have the highest chance of working, with minimal risk.

1:  Same idea, different socket and bulb.  Here’s the link to a guy on YouTube doing his version of this, using a 25 watt incandescent bulb (link).  He feeds the electrical cord through the end of the foam cover, rather than cutting a slot in the foam cover.  But it’s basically the same notion as what I’ve presented above.

2:  Make up a candelabra-base fitting from parts.  Let’s say you can’t lay your hands on the candelabra-base fitting that I used.  But you want to use more wattage than a night-light can handle.  Substitute a standard two-wire extension cord plus a socket-to-light adapter plus a medium-base-to-candelabra base adapter.  At my local Home Depot, those two adapters are available as this part, and this part, for a total of about $5.50 for the two of them.  That way you can still put a small night-light-sized bulb inside the foam faucet cover.   Instead of cutting a small hole, for night-light, as above, cut a hole, for the end 1″ wide end of the candelabra-base adapter.  Then proceed as with the original model above.

 

3:  Cheap trouble light, “60 watt” CFL bulb, and a cotton towel:  30 degrees F of heating.  By “trouble light”, I mean a plug-in 120-volt socket with a cage surrounding the bulb, and a hook for hanging it.   Like this, $9 (no cord, Walmart) and $16 (with cord, Lowes), respectively.

The point of the cage is to keep stuff from contacting the hot bulb.  Put in a moderate-wattage bulb, hang it on your faucet with the open side of the cage facing the wall, and then insulate it however you can, taking care that nothing touches the bulb.

Above is an example I tested using a towel, a plastic grocery bag, and a “60 watt” compact fluorescent, which actually draws 13 watts.  (And the world’s cheapest plastic-cage trouble light.)  Poke the lamp cord and the handle of the trouble light through the bottom of the bag.  Arrange some towels around the light, being careful not to touch the bulb.  Hang the light on the faucet, pull up the grocery bag, arrange the towels for best coverage, and tie the handles of the grocery bag on top of the faucet.

If you do this, be sure to come back and check it to make sure nothing is burning.  And, obviously, don’t leave this out in the rain.  (But if it’s raining, presumably you aren’t worried about your pipes freezing.)

As shown — “60 watt” (actual 13 watt)  CFL bulb, one bath towel — this produced at least 30F of heating above ambient temperature.  Obviously, YMMV.  If you have a kitchen thermometer, nothing will stop you from measuring how well yours does, before you trust it to keep your spigot from freezing.

If all you can get your hands on is an LED light bulb, bear in mind that a “60 watt” LED bulb only uses about 7 watts.  So you’re only going to get as much heat out of that as you would out of a 7-watt night-light bulb.  With this setup, I wouldn’t count on more than about 20F of heating, maybe less, with a “60 watt” LED bulb.

If all you can get is an incandescent bulb, I would not use more than a 25-watt incandescent bulb here.  Maybe not even that much.  It’s just going to get too hot.  You’ll risk (e.g.) melting something inside your cheap trouble light, or setting setting the plastic grocery bag on fire.

4:  A completely different approach:  Use a string of miniature Christmas lights, towels, grocery bag, and duct tape.  I’ve seen this one mentioned on the internet, and it seems like it should work, given the wattage involved.  You just need to have some reasonable wattage of lights, something between (say) 5 and 20 watts.  Wrap a string of miniature Christmas lights (either mini-incandescents or LEDs) around the exposed pipe of the outdoor faucet.

The rest is as shown above. Wrap some towels on top of that, for insulation.  Put a plastic trash or grocery bag on top for waterproofing.  Maybe duct-tape the entire thing.  Maybe just tie the bag on, as shown above.

As with the trouble light, check it after it’s been on for a while to make sure nothing is burning.  I would not do this with full-sized (C7 or C9) incandescent Christmas lights.  Those bulbs get hot — they run about 6 watts each — so even a short string of those can run to more than 100 watts.  That’s a LOT of heat in a very small space, and suggests a pretty significant fire risk, to me.  A string of (say) a dozen such bulbs emits vastly more heat than I would consider safe in these circumstances.


Some totally unnecessary background.

I guess the target audience for this post is people like me:  Southerners, facing a few bitterly cold nights a year, who would rather not mess with trying to winterize their outdoor faucets the proper way.  I’d rather run an extension cord to the faucet than hope that the 60-year-old sillcock shutoff — that hasn’t been used in at least 30 years — will work without leaking.

In my case, I was motivated to install one of these by a recent 11F night, after which water would only trickle out of my outdoor faucet, suggesting it was very nearly frozen solid.  This, despite using a standard foam faucet cover.  Given the damage that a burst pipe can cause, adding some heat to that seemed like a cheap bit of insurance.

I looked around for something I could buy, but came up empty.   Sure, there are heater tapes sold to keep pipes warm.  But those come in (e.g.) 30-foot lengths, and consume hundreds of watts. Overkill for a single outdoor faucet.

Near as I could tell, there doesn’t seem to be any product made to provide electric heat to a single outdoor faucet.  I assume that’s because you’re supposed to winterize these by draining them.  It’s only people who don’t want to do the right thing — shut off and drain that outdoor fitting — that would need something like this.

Which is how I ended up making these for my outdoor faucets.  For me, this is the simpler solution, for a few days of cold weather a year.

One final extras-for-experts: Post #1666.  Sure this works in practice, but does it work in theory?  The answer is yes.  In that post, I do the math.  Starting with the R-values for Styrofoam and brick, the dimensions of the faucet cover, and the heat output of a 4W light bulb, I calculate a steady-state 28F temperature difference between the inside and outside of the cover.  Which is, purely by chance, exactly what I measured.