dual capacitor question

[KtRoP]

Hi everyone.
I'm working on a condenser that had a blown 30/4 370vac370 capacitor in it.
no supply house I called had it in stock so they told me to use a 30uf for the comp and a 4uf for the fan.
They said just to hook up the wires the same way they were on the old one with no need to jumper the 2 commons.
So I did what they said and only the comp kicks on, not the fan.
am I correct in believing that I have to jumper the 2 common terminals?
Or can something else be the reason for the fan not kicking on.
please help.

[Mr Bill]

You have to jumper the common from the dual cap to one side of the single 4uf, and plug the wire that was on the cap terminal of the dual cap, to the other side of your new 4 uf. If you did it this way the motor should work.

[Cooked]

Yeah, sounds like your not getting line voltage to the fan

[KtRoP]

That's what it was.
I had to jump the 2 common terminals on the capacitors which is what I thought.
Just wanted to double check myself.
Thank you for your help!

[54regcab]

Cap can't work if both sides aren't hooked up, just sayin

[KtRoP]

Ya, that's what I thought but I am a recent tech school graduate and was told by the people at the supply house that no jumper was needed so just wanted to make sure I was on the right track before trying anything.

[Milk man]

Now you know about the advice given at some supply houses.

And, BTW, direct you attention to my signature line.

[gesellman]

30-4 Ive seen those on smaller trane units many times. Trane dealer/supplier should have them in stock... If wiring two caps together you have to wire the common together on both caps and to the com from contactor and one wire to fan on the 4 cap
and another to herm on the 30 cap. its fairly straightforward. If they said no jumper was needed they may have thought you had a condenser motor with two brown capacitor leads... if thats the case you wont need a jumper.

[Mr Bill]

Now you know about the advice given at some supply houses.

+1

[Kevin Weaver]

I bet you could of used a turbo cap. Usually its says 5 uf on the sticker but if you measure it with your tester its less than what the sticker says. If I need a 50 uf for instance, I connect the 30 and the 20, measure with my tester and its reading only 46-47 uf, so I add in a 5 uf to the equation and now reads 50uf.

[KtRoP]

The turbo was another option but it was 5 times the cost of buying the 30 and 4 uf separate.

[jedihvac]

Turbo's can be pricey, but cheaper than going to the job twice. Plus if there hot, they usually will pay up! I keep Turbo's just for those odd ball sizes. If you have a Rheem or Ruud supplier around, they should have those capacitors.

[mgenius33]

Turbo's can be pricey, but cheaper than going to the job twice. Plus if there hot, they usually will pay up! I keep Turbo's just for those odd ball sizes. If you have a Rheem or Ruud supplier around, they should have those capacitors.

Yeah, if you add in travel cost, your time and possibly an evening or Sunday without cooling, the extra cost is a better VALUE. Many techs worry too much about dollars and cents. A majority of people will go with value and benefits even if the cost is greater, within reason.