Dual cap question
#1
07-06-15, 10:23 AM
Dual cap question
i came home yesterday to a hot house. I checked the breakers and everything was good. i then went outside and heard the compressor running but the fan was not, the fan was hot to the touch. I then turn the unit off to let it cool while i do some research. after about an hour i turn the unit on and ran out side and easilystarted the fan with a stick. however when the house reached the desired temperture the unit cut off and when it came back on the fan once again had to be started by a stick. so after some more research i decided i needed a new cap. But when i opened the side of the unit i found the cap was wired strange with nothing on the com point on the capacitor. i have ordered a new one with the same specs but was wondering if i should wire it the same way the unit has been woring well since last spring when i had a professional come out and work on it (he changed the cap).
the following is a picture of how it is wired
http://i12.photobucket.com/albums/a2...psc38afb76.jpg
thank you for your help
paul
the following is a picture of how it is wired
http://i12.photobucket.com/albums/a2...psc38afb76.jpg
thank you for your help
paul
#2
07-06-15, 10:32 AM
Member
Perhaps when the tech changed the cap last year, all he had with him was a dual cap, even though you only needed a single cap. If everything has been working okay with it wired the way it is, I would be inclined to wire it the same way it currently is. Is there a wiring diagram inside the cover? If so, does it show 1 or 2 caps being used?
#3
07-06-15, 12:03 PM
It looks like the red and purple wires on the common. I see a transformer in there, just curious what the make and model number is.
#4
07-06-15, 01:32 PM
You are correct sir. I had confused my self nothing was hooked to the fan. I just found the other capacitor zip tied in the same enclosure as the fan. It was a 10 mfd and the can only had a 5 mfd built in. I tested the 10 mfd and it test slightly out of range of +- 3% at 9.61. So I ordered a new one after I hooked my new duel capacitor up that came in today. I am still getting the same results I turn on the air and the compressor starts and the inside fan starts but the out side fan requires a stick to start it and will run till the temperature of the house hits the target temperature then it cuts off and will not restart without a push. I also have to be careful to push it the right way because it will go which ever way I give it a nudge. If this other capacitor does not fix the problem any suggestions or is it time to call a professional. When it is running the temp is set at 68 the temp out side was at 85 and house temp was 75 and the temp blowing out of the vent was 64 and dropping. The make and model on the side of the unit has faded so much I can't make it out.
#6
07-06-15, 03:03 PM
Group Moderator
The cap needs to be the required size to match what is printed on the fan motor. If the cap is correct and new..... it may be time for a new motor.
#8
07-06-15, 06:50 PM
The old cap was 35/5 440 and I replaced it with the same. However it had nothing was connected to the fan terminal. So after I replaced it and got the same results as before I started digging and found a second capacitor in the area with the fan and compressor, it was 10mfd but when I tested, it was 9.61(slightly out of the range of 10mfd +/- 3%) so now I have ordered another new capacitor to replace that one. It is supposed to come in tomorrow.
I also have a question about the delta t. How long should the unit be running before checking it(the unit had been off all day) right now the house is at 77 and the air in the vent is 58 the unit has been on for about 40 mins.
Thanks again for everyone help.
I also have a question about the delta t. How long should the unit be running before checking it(the unit had been off all day) right now the house is at 77 and the air in the vent is 58 the unit has been on for about 40 mins.
Thanks again for everyone help.
#9
07-06-15, 06:58 PM
Group Moderator
The old cap was 35/5 440
If it should be a 5 and you put a 10 in its place..... it will allow too much power to continue flowing in the start winding.
#10
07-06-15, 07:24 PM
http://i12.photobucket.com/albums/a2...ps411c7a6a.jpg
http://i12.photobucket.com/albums/a2...pse2dd2095.jpg
http://i12.photobucket.com/albums/a2...psc32135f6.jpg
The fan calls for 10 mfd and the cap hooked the the fan was 10 mfd. The compressor capacitor was a duel 35/5 capacitor but nothing was actually hooked to the fan terminal.
http://i12.photobucket.com/albums/a2...pse2dd2095.jpg
http://i12.photobucket.com/albums/a2...psc32135f6.jpg
The fan calls for 10 mfd and the cap hooked the the fan was 10 mfd. The compressor capacitor was a duel 35/5 capacitor but nothing was actually hooked to the fan terminal.
#11
07-06-15, 07:31 PM
Group Moderator
#12
07-06-15, 07:51 PM
I noticed from the pictures I took the fan was 208 to 230 vac and the capacitor I am going to replace was 440 will that hurt anything replace the existing cap with the same 440 spec. When it comes in tomorrow?
#13
07-06-15, 08:09 PM
Forum Topic Moderator
370VAC and 440 VAC are your 2 options for that motor.
440VAC is the better choice.
3% is the specs on that cap but most say 6% or 10%. The old cap would pass if I was checking it.
There is a second method for testing a cap using a volt meter and an a clamp Amp meter. If both methods are within 10% the problem isn't the cap.
That motor looks fairly new. Has the drain plug on the bottom of the motor removed? It should be.
440VAC is the better choice.
3% is the specs on that cap but most say 6% or 10%. The old cap would pass if I was checking it.
There is a second method for testing a cap using a volt meter and an a clamp Amp meter. If both methods are within 10% the problem isn't the cap.
That motor looks fairly new. Has the drain plug on the bottom of the motor removed? It should be.
#15
07-07-15, 03:58 AM
Super Moderator
I am going to replace was 440 will that hurt anything replace the existing cap with the same 440 spec.
I dont think you want a 370 or 440..
Whats the model /make of the unit?
#16
07-07-15, 06:01 AM
So I called the previous owner of the house and she informed me that the unit did have the fan changed by a professional 2 years ago. I am not sure about the drain plug I will check when I get home today if the drain plug was not pulled does that mean my motor is gone? My new capacitor is supposed to be in today using the same specs as what is in the unit.
The sticker with the make and model is so faded I can't make it out. I am including the picture of the in side wiring diagrams
http://i12.photobucket.com/albums/a2...ps83bd310e.jpg
http://i12.photobucket.com/albums/a2...ps9908750d.jpg
The sticker with the make and model is so faded I can't make it out. I am including the picture of the in side wiring diagrams
http://i12.photobucket.com/albums/a2...ps83bd310e.jpg
http://i12.photobucket.com/albums/a2...ps9908750d.jpg
#17
07-07-15, 08:35 AM
Member
Opening one of your images in Photoshop and manipulating it, I was able to read the model numbers on the Blower Speed Connection diagram. They are:
Model Ref Blower Speed
PHP/RPH 10A24DA Med
PHP/RPH 10A30DA Med
PHP/RPH 10A36DA High
PHP/RPH 10A42DA High
PHP/RPH 10A48DA Med
PHP/RPH 10A50DA High
Model Ref Blower Speed
PHP/RPH 10A24DA Med
PHP/RPH 10A30DA Med
PHP/RPH 10A36DA High
PHP/RPH 10A42DA High
PHP/RPH 10A48DA Med
PHP/RPH 10A50DA High
#19
07-07-15, 02:45 PM
Forum Topic Moderator
I have a van full of 370 and 440 volt run caps that I use on 240 volt and 120 volt motors. I usually measure around 330 to 370 volts when I measure the voltage across the 2 cap terminals. If you also measure the cap amperage you can calculate capacitance.
Cap Amp/Cap Volts*2652 = capacitance
So if you measure 4.37 amps on the start wire and 333 volts between start and run...
4.37/333*2652 = 34.803 uF
I have an excel program that I use for AC checks. It is great to be able to check a cap without removing power. Some units lock out on error when you turn off line voltage.
I also commonly see 120VAC start caps on CSiR motors even though the motors are used on 120 volt and 230 volt applications.
Cap Amp/Cap Volts*2652 = capacitance
So if you measure 4.37 amps on the start wire and 333 volts between start and run...
4.37/333*2652 = 34.803 uF
I have an excel program that I use for AC checks. It is great to be able to check a cap without removing power. Some units lock out on error when you turn off line voltage.
I also commonly see 120VAC start caps on CSiR motors even though the motors are used on 120 volt and 230 volt applications.
#20
07-07-15, 03:10 PM
Super Moderator
Dont know how long these been out but I have seen them at the local supply house... Irrelevant probably, but speaking to the service guys they often use them for test purpose to rule out the cap...
Up to 260 different values
I would still have an issue with the different voltage and uF values as shown..
Talking to supco for my RV start cap they suggested that their e series with relay would be iffy and rated at 370v. They suggested the reg cap with the PTR/ptc. Rated at 120v...
But this was my hard start issue cap.....
http://www.supco.com/web/supco_live/...t=1&category=1
I have the dual run/fan here and that should be uf rated for the compressor from what I know.. over or undersizing can be bad. Your ac will not last long... Same for the start cap. there is a limit..
http://www.supco.com/web/supco_live/...t=1&category=3
Up to 260 different values
I would still have an issue with the different voltage and uF values as shown..
Talking to supco for my RV start cap they suggested that their e series with relay would be iffy and rated at 370v. They suggested the reg cap with the PTR/ptc. Rated at 120v...
But this was my hard start issue cap.....
http://www.supco.com/web/supco_live/...t=1&category=1
I have the dual run/fan here and that should be uf rated for the compressor from what I know.. over or undersizing can be bad. Your ac will not last long... Same for the start cap. there is a limit..
http://www.supco.com/web/supco_live/...t=1&category=3
#21
07-07-15, 03:29 PM
Thank everyone for all your help. The new capacitor came it today and installed it and I got the same results the fan had to be started with a stick. However, when I took the fan out again I found a small yellow wore that was had been exposed to the weather and became brittle and burnt in 2 but was still connected by the underneath rubber coating. I replaced that wire and now it is starting right up with out the push from the stick.
Service call would have cost 75 to show up.
My cost
35 uf cap 21.52
10 uf cap 17.45
18 gauge disconnects 3.99
Total cost 42.96
I have also learn a lot from ya and all the other posts I researched before I started.
Thanks again for all ya help.
One last question since I replaced 2 cap that did not need changing would ya keep them in case my new ones go bad or since they are used just disposal of them.
Grateful for ya help
Paul
Service call would have cost 75 to show up.
My cost
35 uf cap 21.52
10 uf cap 17.45
18 gauge disconnects 3.99
Total cost 42.96
I have also learn a lot from ya and all the other posts I researched before I started.
Thanks again for all ya help.
One last question since I replaced 2 cap that did not need changing would ya keep them in case my new ones go bad or since they are used just disposal of them.
Grateful for ya help
Paul
#22
07-07-15, 04:26 PM
Group Moderator
