Hello , I am told that I need a new ‘power board ‘ for my sharp al-1644 copier after a surge after a power cut? I am getting an H4 fault . Can you help with this , Thanks Terry

Pack it back up and take it back and get a replacement.

Hello, NICOLAS

Let me give you, a url when you can find sharp error codes and fix by youself, if you have any other cuestion, please write a comment, im here for help you.

How to solve the h4 subcode 00 error message on sharp AL-2030 copiers

http://www.en.rellenadodecartuchos.com/2014/05/how-to-solve-h4-subcode-00-error-message-on-sharp-al-2030-copiers.html

thanks for comment if need more help

H4 00 Heat roller low temperature detection

To reset the H4 condition on just about any Sharp AL series copier press the following key's in sequence and as quickly as possible (with 4 seconds for the first 4 keys)
Press "C" then the far left key (exposure mode) then the "C" key then the far left again.
So in other words C, far left, C, far left
Some model's use 2 other initial codes, so you may need to use one of these 2 alternate codes to get your display to go blank. The rest of the procedure is the same.
Alternate codes are: #, * , C, * or pound,star,C,star and also
#, Interupt, C, Interupt
If done correctly the display should go blank.
Now key in 14 as if you were going to make 14 copies.
Now press the print button.
The machine should reset and the code should be gone.
9 times out of 10 this is a false code that pops up due to power surges or noise.
If the code comes back this means you have a heater lamp or thermal fuse (more common) failure in the fusing area and will need service.

Hello my friend.
It is a fuser temperature error or one of the sensors is dirty.
You could try removing the fuser assembly - ensure power is switched off- then try cleaning the sensors as they tend to get paper dust and melted toner which collects between the surface which senses the heat from the fuser `Hot` roller.
if this doesn't fix it you may need to replace the fuser.
There is also an engineer code that you can enter to clear the fault
PRESS: Clear - exposure - clear - exposure = the LED display will turn off.
PRESS: # of copy keys until you have 14 displayed.
PRESS: Enter.

Hello sir;Follow these steps within 4 seconds; press 'clear', "exposure" ,"clear" "exposure" then enter 14 hit print, should be OK.

This works on MOST sharp AL series copiers.
Press these keys in sequence:
Clear → Density select → Clear→ Density select
display should go blank. Then enter:
24 as if you were making 24 copies then press print
then enter 7 as if you were making 7 copies then press print
if successful you should see flashing 000
turn machine off then on again and the drum light should be gone.
Good Luck

You may have a busted thermostat or heater lamp.

H4 is a fuser roller heating issuse. The temperature isn't hot enough. May need new fuser roller assambly or a thermistor.

Usually CH indicates that one of the doors on the copier is not closed properly, if it is a flashing CH then there is no toner cartridge in the copier or the cartridge is of the wrong type for this machine. A lot of toners for this machine look alike but are not the same for the machine.