Capacitors

Capacitors on a heating and cooling units are used to help motors get started and keep motors running properly. I compare capacitors to the battery of a car. If the capacitor is weak the motor/compressor may not start up or overheats after it runs for a little bit.

Capacitors should be checked each maintenance. My own Air Condition had a capacitor that was starting to get weak,but not at the point that it had to be changed. Well two months later I had to change it. The top of my capacitor looked like a bullfrog. A tech should have a meter to check the capacitors to see its strength level or resistence level. If a tech says a capacitor needs replacing ask him to show it to you, just say so you can tell your spouse. I always show my customers just to make them feel comfortable with me. Weak capacitors can damage the motor/compressor and cause higher electric bills. Capacitors are suppose to be changed once the get 10% of their rated value. I would suggest changing them even if its borderline due to my own personal experience, cause two months later I had to change mine. This will save a service call charge and the inconvience. Next visit I will address contactors.

Recommended reading: click here

Freon Level

A systems Freon level is critical for a system to cool or heat properly. If a system is overcharged or undercharged it will not cool/heat properly and will eventually damage your system.

Just this past week I went on a service call for a noise complaint. The customer said the heat pump was very noisy and that he put a 20lb dumb bell on top of it to get it quite.

I went out there to check it out. The customer was not home,but left me a key. I turned on the system and removed the weight and as soon as I did that the unit made a loud noise like two metal panels were loose or shaking. I checked for loose screws and put vibration pads under the unit,but it was still loud and unfortunately the unit is right at the master bedroom window. So I decided to check the charge. The weather that day was in the mid 60's so I checked out both the cooling/heating cycles. I found the unit was overcharged, I removed around 3 lbs of Freon. I then set my pressures in the cooling mode by what we call "superheat" and rechecked the pressures in the heat mode with its chart in the panel. Guess what? The unit is much quieter.

Now some might say 3 lbs is not much,but over charged systems will your compressor and make your system less efficient. So if you get your system checked ask the tech if your charge is good and how they determine it. Mention you heard or read about superheat on systems charging, if they do not know what you are talking about, I would not use that company again.

They should be able to explain it to you very easily. This is a brief explanation on how to determine superheat on a system. This is the method I use for cooling cycle checks. The tech will have to take a outdoor temp. by the unit and a indoor temp. inside near the return. He will either use the chart in the outdoor system or a chart he carries himself. The tech will see what the chart calls for the superheat to be. He then takes a temp. Reading of the suction line, this is the copperline that sweats and is insulated. He then looks at the low side pressure gauge and finds temp. of the Freon in the system,he then subtracts Freon temp from suction line temp. This gives the "superheat" of the system.

If the "superheat" to high you need some Freon if it is to low some Freon needs to be recovered. It is easier to understand when you see it done. It is very critical that the charge is correct. Some tech will charge by other methods, I prefer "superheat" in cooling mode and using pressure chart for heating mode.

Recommended reading:click here.