Tip & How-To about Heating & Cooling

Furnace Diagnostics

If your system is newer than 10-years old, you may have a diagnostic center built-in to your system. This may come in handy when trying to diagnose why the system is not working. Usually there is a LED light on the board. After a few unsuccessful attempts to start, the center logs an error code and blinks it on that LED. Unfortunately some furnaces erase the code as soon as you remove the panel with the door safety switch. Many manufacturers have installed a small viewing port that you can look and see the error code without having to remove the panel. Once you get the error code you may need to either look in the manual or on the "glued-on" wiring diagram to see what the error code refers to. Often it is a starting point and may not give you a precise diagnostic result. If you can't find the codes for your model, you will have to do an internet search for a service manual or error codes for the unit. Always check and clean your air filter, check for blockage of all vent pipes as well as drain hoses and condensate pumps. Sometimes it is the simple things that cause the most headaches.

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Fix an old pc

Generally, it is not worth it. It is not running Windows 7 or newer, forget it. A well made computer has a life of 10 years, a lesser made one 6 to 8 years. I have mine built to specifications based on what i need and how much I am willing to spend.

Additionally, if it is a hardware problem, diagnosing is always difficult. I bought a new processor and that was what the general consensus was the problem. I sourced and paid for a used but warrantied processor that cost me $70 with shipping and fees, only to find it was the motherboard that had gone. I bought a secondhand graphics card before that for $16, but was able to get a refund from my local shop as they built my current computer for $1,100. The new one flies and the graphics are amazing. They backed up all my old data and put it into a folder for me.

If it is software problems you have, give me the details by clicking COMMENT under thispost.

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