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Same sheet every year.. my AC works but i dont think my sensor is sensing... i have similar issues every year..its getting old.. at this point not sure im too impressed with my AC guy... anyone around this area Littleton kipling/chatfield area want to come look at it for me? Will pay of course
Which sensor are you talking about. What kind of system do you have.
I have no clue what im talking about! And my furnace wasnt working... its called something with an H ill have to go down and look at in a bit..about to rest my eyes for a bit.. i kbow my heating and cooling guy said he wasnt real familiar with my system so probably a pos.
Ehhh they all work the same, unless you have an old pulsar unit. They are all the same as the next. With the heat my guess would be a capacitor without knowing what it's doing. Except that won't explain the furnace not working. Of you give some more details of what's going on I'll try to help over the internet
Heat pump maybe?
Got the furnace working.. now the AC unit wont turn off once in house temp reaches what its set at..just keeps running.
Sounds like the thermostat is being flakey. It's a fairly easy DIY.
Nah, its hapoened before and i replaced the thermostate thinking thats what it was too and it still did it so its not that.
Short in the stat wire or welded shut contactor?
My termastat went bad on Wednesday. It was only 8mo old and a nice programmable one.
Any ideas why mine is tripping the breaker it's on? Cleaned coils/filter. It's happened while running so I think that means not just the starter or whatever? Especially with warm overnights lately it certainly has to run hard, seems quite undersized for the house and most days will get a few degree's over where it's set.
Tripping a breaker is mostly due to a shorted load or a locked rotor start.
Any easy way to diagnose before i get the experts. Remedies or beginning of the end?
Check to make sure the breaker is the correct size. Just had similar situation at the job I'm on. Initial diagnosis was the capacitor was bad. After tripping again later that night, found the fan motor was starting to go and the breaker was undersized. So far 3+ days and no trips.
It's on I thought like a 30 amp double switch breaker, so shouldnt be that. When I fist moved in it had a capacitor explode and make a mess. Couple years ago now.
If it's a right sized breaker and still tripping you need an HVAC guy. He will have the meters you need and they cost more than a service call
First try replacing the breaker, it may be weakened, especially after the exploded capacitor and if it is several years old.Quote:
Originally Posted by fitz19d
DO NOT upsize the breaker ! Until you have an Electrician check the wire size to make sure it will rate for a upsized breaker. But as most builders do, is to install the bare minimum wire size that the A/C unit requires.
Also, check for loose/corroded wire connections at the breaker panel, service disconnect near the A/C unit and inside the A/C unit.
The job I'm on has 2 units. One was on a double 20 amp and the one having the issues was on a double 30. Both were wrong. Needed a double 25 and 40. Had the same issue with the capacitor. As the tech was disconnecting it blew a hole in the side and spit it's oil all over the side of the house.Quote:
Originally Posted by fitz19d
Any updates on what the problem was? Didn't get to use my brain today just changed a water heater pan so I could go for some diag stuff
Have not had time to try and address it. Kinda sounds like I'll need the guys with meters. (Some conflicting info and not sure I'm game to be replacing breakers randomly on my own)
Im the original poster and i also have not got my problem resolved.. my thermostat and ac unit are not on the same page. The ac unit just keeps running even though when inside temp reaches set temp and shuts off fan..
Just a helpful tip for any of you with a digital type thermostat. Don't forget those things have batteries in them. Mine does really wiggy things about every two years or so when that internal battery starts running out.
It sounds like you have a bad thermostat or a shorted stat wire if the condensing unit keeps running after the call for cooling is satisfied. Or your contactor is welded shut. But your out side unit running with out the furnace fan running is one of the major ways to damage a compressor. It won't boil off the liquid refrigerant without the indoor fan going, then it sends liquid back to the compressor and tries to compress a liquid( which can't be compressed) and Bam broken internals, or it will wash the bearings and cussed a short. It's known as slugging the compressor.
Good to know.. i have been turning it on and off
I just went through all of this. Here is what I found:
Just to make sure we are on the same page, this is how my system works. Outside unit, powered by 240V 40A circuit breaker, thermostat controls a contractor in the unit outside. The contractor starts both the compressor and the fan, and the capacitor is double poled with a fan side and a herm side separated by a common node. When the thermostat senses high temp it sends a high signal to the AC contractor that closes and applies 240V to the compressor and the fan. The run capacitor is needed because the machine does not have a neutral and acts as running storage while the machine is running to save energy (opposed to dumping it through the neutral to ground.)
The capacitor is run sized to be efficient, and cant be too big or it will sag the voltage. It cant be too small or it will not store enough energy to help start the compressor. As the machine ages or even in some new high efficiency machines the capacitor is just barely able to start the machine. Adding a hard start with drop out relay is the best option. Gives the capacitor extra kick to start, drops out when it is running to maintain system design parameters. They make a 2 wire kit that is just a piggy back capacitor, but you do not want that. You will want a 3 wire kit with the relay so that it drops out after the machine is running.
Here is the tricky part that happened to my machine: The capacitor can short out and still work. Mine reads 0 ohm from common to fan terminal, and OL from the HERM to common. This means that the fan side failed, and the HERM side was still good. But common is tied to ground, and the capacitor had 240 across it. So what happened is the compressor started fine, and the fan ran half speed backwards. Half of the voltage for the fan was shorted out through the capacitor and caused the fan to run on 120V in the wrong direction. I talked to several HVAC techs that I work with and they all confirmed that they had seen that happen but did not know why.
So if your unit is running and will not shut off, it is probably the contactor. They can be bought for $10 on amazon or Home depot had some last time I was looking for one. If the unit fails to start or runs poorly check the direction the fan is turning, it should be blowing air straight up and out. If it is running backwards, I would replace the capacitor and check the wiring to make sure that it was wired correctly. My machine has the internal wiring diagram on the inside of the panel that covers everything. Adding a hard start will not hurt the unit, and will significantly drop your starting current that is tripping the main breaker. Just watch a few youtube videos, and make sure that you are using the machine disconnect AND opening the breaker at your main board. Use the same size contactor and capacitor that your machine came stock with, and add a hard start if you are having issues with it starting. Also know that capacitors store energy and can easily kill you if you do not discharge them before working on them even if power has been turned off.
One final note, when I opened mine there were two big ass wasp nests in there that had gummed everything up and was quite the surprise when they were ~12" from my face when the panel came off.
Hope this helps.