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View Full Version : OT. Ironing machine doesn't get hot enough



Black Forest
11-23-2014, 04:55 AM
My wife says her ironing machine doesn't get hot enough. This is the type with a 6" roller that you feed the clothes into. There are three elements. I have posted on here before about a part that was broken.

So where do I start to trouble shoot this machine? How can I check each element to see if they are working correctly? They all get too hot to touch!

What pictures would you need to help diagnose the problem?

alanganes
11-23-2014, 07:45 AM
Ignore this if I'm stating the obvious, but here is how I would start:

If they are all getting hot, I'd try to measure the current to each individual heater (assuming you have access to those connections) to see if they are the same and if the measured current matches the rated wattage of the machine.

Measure the voltage at the elements or otherwise check for solid electrical connections. Bad connections will usually reveal themselves after a while anyhow by overheating at the bad joint.

If you can electrically separate the heaters, you can measure the resistance of each one (un-powered, of course).

I seem to recall that what you had fail before was some type of thermostat. Are you sure it is regulating at the correct temperature? Can you measure the temp (assuming you know what it SHOULD be)of the roller directly to see if it is too low? Perhaps there are some other temperature regulating elements in there that are not so obvious.

I have not seen one of those machines since I was a kid and never worked on one. So my advice may not be very helpful. Buy hey, it was free!

Somewhere around here I have an old book on appliance repair that has a whole chapter about these things. If you can't get this figured out quickly, I'll dig it up and see what it suggests if you like.

lakeside53
11-23-2014, 01:04 PM
Careful.. it's a set up. When you break it, she'll want a new one. :)

darryl
11-23-2014, 03:25 PM
The basic questions concerning the heating elements are- do they get voltage, and do they draw current. A clamp-on ammeter will tell you both things in one easy test- if it shows current draw, then the voltage is also there.

If it doesn't show current draw, then you need to measure for voltage to the elements also.

Past this, the thermostat is a likely place for problems to occur. The most basic and widely used is a bimetal strip type, where the contacts are opened and closed by the strip bending one way or the other in response to heat. If the contacts are poor, excess heat can be generated at that point, and that can affect the opening of the contacts- they will open earlier than they should. This might actually be where you should first pay attention. Use a point file to re-condition the contacts and see if that clears up the problem. You also want to make sure that any spade connections are tight and clean- if any of these are discolored or loose, they will become a problem for sure, even if they don't currently seem to be a part of the problem.

If the thermostat is electronic, you could have poor solder connections within it. Sometimes it takes a practiced eye to spot these, but sometimes it's obvious. Look at any spots where the high current flows, where there's a lug soldered to a pc board, relay connections, etc.