Overheated Century?

[Jim]

Anybody know what going on here? Lamp had been working great and then the other day I found it like this after it had been running about 10 hours. That's the longest I'd run it in the three weeks I've owned it. Everything I've read online seems to indicate over heating. I turned it off for about 15 hours and tried again and this time turned it off for 18 hours before trying again. This photo was taken after two hours but it looks exactly the same as it has the past couple of days. Thanks for any help. 

[Jim]

Stand by. Seeing some movement. Will report back. 

[LampHead]

Actually it looks to be running on the cool side.

[Claude J]

add to the fact that the coil looks flipped on its side not transferring heat to the lava
LampHead said:

Actually it looks to be running on the cool side.

[Jim]

You guys are right. After my last post the lava flowed better than I had ever seen it. It was on a different base with a different bulb. I assumed because it had stopped flowing after being on for 10 hours that it was an overheating problem, but now I think maybe the bulb was losing heat. The bulb is only a week or two old so I wonder whether it's a result of a cheap bulb made by Walmart, or whether the base is somehow overworking it. I have no idea. I'm gonna put a new bulb on the old base and try it again today. 

[Jim]

So it looks like the lamp take the standard 2-2.5 hours or so to get going, then flows great, and then somewhere around hour six it goes into the dormant phase where it globs up on the bottom and sits there. If I let it cool down for a half hour to an hour and turn it back on again, it flows well for another three hours. Anyone have any ideas? Maybe it's getting too hot and I need a dimmer?

[Mr MaGoo]

You say after six hours it globs up on the bottom.  A hot lamp will have many lava bubbles at the top, lava moved up by heat.  Not sure how old lamp is, possible lava could be getting old, as lava does have a lifespan, so to speak.  Sure others will chime in shortly.  Good luck with lamp.

[Claude J]

try a dimmer and throttle it down once its flowing

[Jim]

Thanks guys. The lamp was made in 1990. Was going to try the dimmer but was thinking I would  dim it a little the whole time. Maybe I will try your idea of bringing it down once it's flowing. Seems like a good idea. 

[Mr MaGoo]

You would be amazed at how little you have to dim it to get a temp change and a difference.

[Keith]

Hot wax at the top is the first overheated stage, then a dome at the bottom.  That's a really overheated lamp.

Mr MaGoo said:

You say after six hours it globs up on the bottom.  A hot lamp will have many lava bubbles at the top, lava moved up by heat.  Not sure how old lamp is, possible lava could be getting old, as lava does have a lifespan, so to speak.  Sure others will chime in shortly.  Good luck with lamp.

[Jim]

Keith, why do you think this particular lamp is overheating? Is it possible the previous owner kept it on too long? You think changing to a frosted bulb or using a dimmer is the solution? Is there anything else I might be missing?

Keith said:

Hot wax at the top is the first overheated stage, then a dome at the bottom.  That's a really overheated lamp.

Mr MaGoo said:

You say after six hours it globs up on the bottom.  A hot lamp will have many lava bubbles at the top, lava moved up by heat.  Not sure how old lamp is, possible lava could be getting old, as lava does have a lifespan, so to speak.  Sure others will chime in shortly.  Good luck with lamp.

[Keith]

So I'm not sure of what steps you took with this lamp.  Are the pictures with a different base than the description you gave of the flow stopping after 6 hours?  I ask because the pictures seem to be of wax that hasn't melted.  

If that's the case, you have one base that may run cool and one that doesn't.  Actually 6 hours is within a normal maximum run time (6 to 10 maximum), depending on all factors.  Those factors being, is the lamp in a draft (it might run cool), is it in an area with no air movement (it might run hot), is it under a vent (it might run hot in winter and cold in summer), is it ran with other lava lamps by it (the combined heat will effect run time), what is the ambient room temp (70 to 74F is recommended).  That brings us to differences in the lamp bases.  Are the bulbs the same?  Are the bulbs the same distance from the globe? (within 1/8 to 1/4 inch is considered proper.  This would be an unusual problem on a century as the socket components and bulb size and shape is generaly consistent)  These are just some things to consider when trying to determine why a lamp runs hot, or even cool.  That's one reason why dimmers are recommended, they allow fine tuning for the spot where you want you lamp.

I hope this makes sense.  I feel like I might be beginning to babble a little, lol