National Dryer

[Logoman]

I have an old National Dryer (N4819G). I have posted about this before. Turn it on in the morning and it runs until you turn it off but then it will not come back on until it cools down. An HVAC guy I know said it sounds like the High Limit Switch may be bad. I have a schematic that has it listed but can not find it on the schematic. Does anyone have the same dryer with schematic that shows this or can someone tell me what it would look like so I can test it?
Thanks

[californiadreamin]

What temp are you operating your dryer at?
What temp is cool down?
If your national has not been modified, then your hi- temp saftey is locacted on the side at
The top of the burner box. It sits above the burner cage.
Take cover off and see what temp high limit is set at?
There will be two wires , one on each side of the mercury switch. One is 110 volt infeed, if the switch
Is operating correctly within correct safety parameters then voltage will go through the other side energizing saftey circuit. If not metal has expanded and mecury switch has tripped which would shut system down . Need the temps you are operating at to confirm. You might be operating on the border of
The hi limit which can be adjusted. Unless you are running at temps machine was never designed to operate at. The above would tell 100% and not guess , which can be very unsafe!
I hope this gives you a path.
Winston
(904)3430848
winstric@yahoo.com

[Logoman]

I spoke to Winston a few times on the phone and explained what was going on. I have been having this problem for a long time and could never figure it out, not even the guys that built the Dryer. Thanks to Winston I found that the Dryer is supposed to have the gas turned off and let the Blower run until the temp gets below 150 degrees. Then you turn it off completely, this takes about 30 min. It would never fire back up right away after I turned it off (the wrong way). Now I turn it off correctly and it will fire back up.
Thank you, Winston
Pete