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Michael, Customer Service
Category: Appliance
Satisfied Customers: 9568
Experience:  I have been an appliance repair tech for over 30 years and will help you solve your problems.
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Have a tff 577 tall freezer, goes down to right temp but

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Hi have a tff 577 tall freezer, goes down to right temp but after a while starts to get warmer and ice forms on grill and draws I have replaced the thermostat PCB but has made no difference what's wrong ? Main PCB ? Phil

Hi Phil , I am Tech Michael an expert in this field and I will be assisting you today. I am a Master Technician that's dedicated to giving you the best Answer possible.

If you are new to the site, this is briefly how it works:

1. We may need some back and forth to exchange information (if needed) and there is no extra cost for replying.

2. I will give you the best possible Answer for your problem without the ability of actually being present with you.

The better you describe the problem

, the quicker I can help ;-)

3. Remember to leave a Positive Rating ,it doesn't cost anything additional to rate kindly;-)

I am only credited for my time and expertise if you rate kindly.

Have you replaced the defrost heater and Bi metal sensor, those two part are the most likely cause of this problem;-)

In any case, I will stick with you until this is complete.

Please rate my service thus far.

Also it is the only way I am credited for my time and expertise with you.

Once you rate, I will be notified and will add your question to my priority list so you can reach me anytime until this problem is solved.

Then you can reach me by simply replying to this message anytime.

Thank you Phil.


Tech Michael

Customer: replied 1 year ago.
Hi Michael
The freezer is a new graded item with minor damage to the bottom of the case i bought it some one who got it from a shop that was closing down and not been used as i said the freezer when switch on it goes down to the correct temp but after a few hours it starts to ice up and the temp rises I understand the sensor could be faulty but would the heater be needed after a few hours running where is the sensor is it the smaller oh the plugs going into the thermostat PCB?
Thanks Phil

Hi Phil thanks for the reply,

its likely just the bimetal sensor. It's clipped to the cooling coils behind the inside wall freezer access cover .

But once you get in there you need to also check the defrost heater for resistance to make sure it didn't get damaged during the accident you say it seems to have had;-)

There really isn't anything else that would cause this problem.

If your unit has a fan, make sure it is running. WHat happens is the freezer will ice up internally on the coils blocking the airflow, then the temp inside the freezer WILL rise because there is no good airflow around the coils but it will also freeze up inside but not keep things cold like they should.

I hope that helps Phil?

Please rate kindly so I can stick with you until this is complete and working as it should.

Thanks and have a great day!

Tech Michael

Michael and other Appliance Specialists are ready to help you
Customer: replied 1 year ago.
Hi how do you get the inside top cover off taken all the draws shelves out plus the five screws still won't come out don't want to force it? Phil

Hi Phil the screws should come out if you turn them to the left. These can be a little stubborn.

You can try a little solvent on them.

Please send me so pics so I can be of yor setup inside so I can advise you getting the shelves out of the way;-)


Tech Michael

Customer: replied 1 year ago.
Hi Michel
As I said I have removed the shelves/draws and the five screws 3 from the top grill 2 from the back but the cover won't come out does anything else hold it in didn't want to force it or is it clipped in and you have to just pull?Regards phil

Hi Phil,usually once all the screw are out, you need to kind of pry it from the back to remove it.

Let me know how it goes, make sure that cover is the one where to vent is and coils are located.

It should come out pretty easy but may require a little pulling.



Customer: replied 1 year ago.
Hi Michael
Won't move everything move not just the cover I have sent a couple of photos

Hi Phil, Im a little confused, the second pic shows it partially open?

You kind of have to finesse it carefull out of the way

Customer: replied 1 year ago.
Not sure if you got my reply, pulled cover down to show sensor is it just the plastic cover that comes away there is foam attatched does this come away with the cover Phil

Hi Phil can you see the defrost heater element?


Customer: replied 1 year ago.
Hi Michael
No just the coils and fins can see the fan at the very back which is working, I am also see the thermostat sensor at the front but goes behind the side, to the thermostat PCB ? and no way of getting it out,
plastic cover will move no more than 35mm and seems attached can't see any other fixing apart from the five I have removed. Phil

Hi Phil, these parts are replaceable, perhaps you need to enlist someone with a bit more techy knowledge?

I will help anyway I can.

Customer: replied 1 year ago.

Hi Phil, let me check to see if there is a diagram for doing this repair.

It may take a day or two.

But Im on it ;-)