Do AC Capacitors matter?

[mpire]

I'm looking at the caps on my 3.5 ton system and thinking its been really hot lately and I was going to order a backup.

Looks like I have a 5MF and a 50MF caps, that seems standard.

POCFD555 vs POCF5 + POCF50

My neighbors tossed their AC and I scavenged the spare parts and they had a combined cap.

Is there any difference between getting two different caps or a two in one?

Do brands matter much when it comes to these things?

Also, does it matter than the combined cap is 55MFD instead of the 50MFD I have now?

Just curious.

 

[zmaxmotorsports]

A 55/5 will work fine,its ok to be a little bigger just don't go smaller.

 

[Ohmthis]

Using a combined or duel capacitor is perfectly fine. As for the over sizing, you have to be careful. The capacitor changes the phase angle of the motor's electrical usage. It uses this to give the motor a boost so to speak. By raising and lowering the size of the cap, you change the phase angle and with it the other measurables of the motor (amps, torque, and heat). In this case (10% or less) you will be good, but much more you can push the compressor or fan motor out of their design and hurt them more than most would think. Sorry to give you way more than you probably wanted to know, but I just had to explain.

 

[Fixin'Stuff]

Electrically they are the same. If you look at the wiring diagram, the common side of your dual caps are wired together. On a dual cap, both commons are wired together inside the cap. As long as you make certain to connect C-to-C, Fan-to-Fan, and Herm-to-Herm (The compressor) then all is well.

It's also a good idea to keep a spare contactor on hand. They seem most likely to fail on a Friday night of a long weekend, when everything is closed. If you plan ahead, Amazon has a single-pole, 30 amp one for less than $8, or a 40 amp rated model for less than $11. Around here the local parts houses price them at $40 and up, knowing that most people need one RIGHT NOW.

 

[zeeway]

This is an example of why I am so impressed with this forum...you can ask just about any question, and get an informative answer.

 

[mpire]

I paid about $150 for my last cap & installation, so I was thinking ahead.

My unit has a 5mf and a 50mf cap, the neighbors unit had a 55+5 combined cap installed when they replaced the unit.

I have the last working original AC system on the block, so I salvaged all the electronics and computer boards out of it just in case I might need them in the future.

 

[rshadd]

I keep a spare on hand...