Zd-939l (main 939a-ver 4)

[promo7uk]

No heat at all from unit,

replaced. Element in reflow hot air head end

replaced bmt08 8amp 600v triac, nothing

display just reads, error.. Nothing,, not even room temp 0.25 as it should start,, has anyone else had this purchased 2 of ebay. Faulty but brand new ,,, u can see never been opened, im now looking at bmt137 triac. As i have removed this next to optocoupler and still dead, doing the same., so maybe optocoupler or this triac, anyone else. Any info on these cheers, its duratool zd-939l

[promo7uk]

Re: Zd-939l (main 939a-ver 4)

Found two issues and fixed,, old element temp core sensor was faulty. And wire from temp in element to main 939a ver4 board was faulty at crimp... On 2 of these just goes to show how crap they are,

[stj]

Re: Zd-939l (main 939a-ver 4)

why crap? you got faulty returns - there are a huge number out there that work fine.

[sam_sam_sam]

Re: Zd-939l (main 939a-ver 4)

Found two issues and fixed,, old element temp core sensor was faulty. And wire from temp in element to main 939a ver4 board was faulty at crimp... On 2 of these just goes to show how crap they are,

I have found the same thing with the company that makes these units there quality control has lot to be desired

In the Desoldiering Gun units this sometimes can happen that the temperature sensor goes bad this also happens with the soldering irons as well

The temperature controller board starts having problems controlling the temperature swings are wider to point that really can not use any more or the back light stops working or the switching power supply take a shit

[sam_sam_sam]

Re: Zd-939l (main 939a-ver 4)

No heat at all from unit,

replaced. Element in reflow hot air head end

replaced bmt08 8amp 600v triac, nothing

display just reads, error.. Nothing,, not even room temp 0.25 as it should start,, has anyone else had this purchased 2 of ebay. Faulty but brand new ,,, u can see never been opened, im now looking at bmt137 triac. As i have removed this next to optocoupler and still dead, doing the same., so maybe optocoupler or this triac, anyone else. Any info on these cheers, its duratool zd-939l

Check and see if the the temperature controller is sending a 3 volt signal from the connector that only has two wires that go the optic sensor

You do have to have the temperature on the display show 77*F or you will not have this 3 volt signal try powering a LED on those two wires

If you do not get the 3 volt signal with the 77*F showing on the display then the temperature controller has taken a shit

One note you can take the two wires that go to the temperature sensor and short then together
BUT only do this to see if can get the 3 volt signal only you will not have any temperature control

I have about ten of different types of units that all use the same temperature controller
I have had to work on these units many times in the past

If you need a new temperature controller board you can buy them on eBay also the heater element with the temperature sensor are available on ebay

If you need any other information just ask me and I see if I can answer your questions

[sam_sam_sam]

Re: Zd-939l (main 939a-ver 4)

Found two issues and fixed,, old element temp core sensor was faulty. And wire from temp in element to main 939a ver4 board was faulty at crimp... On 2 of these just goes to show how crap they are,

Were you able to fix your unit