"I am a hvac student ..."

Without an EPA refrigerate card you will be hard pressed to buy anything to charge the system.At the very least you need a gauge set and thermometers.

Without having to use a gauge set, you could take 2 dial thermometers and at the outside of the condenser where the line sets start to enter, tape the stem of one to the high side line and one to the low side line. Let us know what the temperature differential is.

"Without having to use a gauge set, you could take 2 dial thermometers and at the outside of the condenser where the line sets start to enter, tape the stem of one to the high side line and one to the low side line. Let us know what the temperature differential is.

Irisman, would you please elaborate on your procedure?

Thanks.

V

All you can tell with just thermometers is that the system is not working correctly.

Sort of.

I'm aware what normal air temperature splits (indoor, i.e., delta-T), but iris is talking line temps.

V

Both the suction and discharge lines are the same temp by feeling them, neither warm or cool. I checked the compressor with my meter, it is rated at 50 LRA, it read: 1.0 from run to common, 3.0 from start to common, 4.0 from start to run, O.L. from common to ground. I cleaned the condenser coils also, it is is not dropping the temp inside.

The next step would have been to ask the OP to give both a dry bulb and wet bulb temperature. He's a student and he is asking for help. Why not give it to him in a way he and others who read the post can learn something and carry it with them the rest of their life?. Any of you folks who believe you cannot determine the charge and efficiency of the unit by this method, are not fully knowledgeable in the field, I don't care what license you claim to carry, what school you claim to have gone to or how long you claim to have been doing it. This is basic stuff. It's a science, not a theory. If you want to learn, fine, I'll help. That's the problem out there, so many of those who don't know this stuff make it look bad on the ones who do. The OP is a student, why shouldn't he know everything from the ground up. We already know just because someone has a set of gauges and a can of gas and a cfc certificate, doesn't mean they know what they are doing. Look at the issues in this forum and that is evident. But if you want to sit like a snake and dispute everything anyone has to offer in these forums, for crap sakes, don't bother to log in, go somewhere else. It's the same old people with nothing to offer but will dispute just about anything someone has to offer. I'm not about to sit here and argue further with anyone about this. You can snort and mouth breathe all you want, these are facts.

Irisman, slow down, I'm with you. I was surprised to see someone else knew about the method!!! You made me roll on the floor!!1 I've been lurking these forums for quite a while and you're right about the snakes!!!!

As anyone with knowledge or experience with these things knows, it could be any number of things. Sitting miles away from someone and giving an exact cause to a problem is impossible. The man doesn't have some of the tools. There is more than one way to skin this cat. For example, he says the fan sounds like a toilet flushing. Anyone with experience has seen situations where the set screw has come loose on the squirrel cage and the shaft spins inside the blade mounting. Nope, he won't get to temperature that way either. But do we know that yet? No. The man needs a methodical way to trouble shoot and learn at the same time. Is the compressor even running? I don't know, I haven't seen anything other than the 2 red lights that indicate everything is ok are on. Anyone here with experience seen these things malfunction? I sure have. But, if he's going to go through the trouble of finding out if the unit is running, why not get all the information possible from the activity. Let's not teach him to be a gas bottle jockey, give him some real troubleshooting knowledge. Many times I( sit here and watch when the snakes wait for someone else to offer help and then jump in snorting and mouth breathing and start disputing everything and all of a sudden, they are experts. At the end of the post, nothing was achieved and the ego maniac goes on to do the same thing in other posts. Have you noticed through the years where the guys who know their stuff don't even post help here anymore because of it.

By the way OP, you can bypass all the boards while trouble shooting. You don't have to be a parts changer until you hit the right thing. You can narrow this right down to the problem. I have my suspicions what is wrong, but I think you will fare much better trouble shooting in a methodical way that will make you a lot of money in years to come. It's easy to say "hire a professional" or "you'll burn your house down" or "you'll get a $10,000.00 fine" or without guages and a can of gas you really can't do much". That's all baloney and don't let the naysayers discourage you. Like I said, it's a science, knowledge is power. If you're in a hurry to know what is wrong, let the so called experts blow their self proclaimed knowledge at you. I'll just watch.

I do have 2 thermometers but I don't see any use putting them on the lines when I can feel that they both are the same temp and I know the discharge line should be hot and the suction line cool. I can take a look at the squirrel cage, I didnt think to look at it since I could feel the air at the filter on the top...anyhow thanks for the help...I think???

Check to make sure the compressor is even running.

You said the 2 lines were the same temp., just a quick guess, were they at ambient temp.? You think? ok, I get it. That door slammed shut!! I'm sure the others will make you know for sure. From the advice you got so far, good luck.

my ac is not dropping the temp when I put it in cooling. The indoor fan comes on (When it kicks in it sounds like a toilet tank running when the handle is loose). since the setpoint is never reach it stays running. The outdoor fan runs, I checked inside the unit outside and on the circuit board with 2 flashing red lights, the info said both lights flashing equals normal. What could be causing my ac to not drop the temp? I am a hvac student so I would like to fix this myself, I just am having trouble finding the source of the problem. I am thinking low refrigerant or the compressor (I haven't checked it yet.) Please advise me.

There are many possible causes; you need a lot more knowledge & the intelligence & wisdom to effectively apply that knowledge in a proper trouble shooting sequence.

To ballpark the operating BTUH of the system, all you need is an anemometer to check airflow CFM & a good accurate wet bulb instrument. Add to that an enthalpy chart to look up the enthalpy change which I have on my HVAC Internet pages.

The formula is: CFM *X's 4.5 at sea level or 4.35 at around a 1000 feet above sea level, *X's enthalpy change as found on the chart using the wet bulb numbers. - udarrell

Here is a link that might be useful: Simple Ways to Check A/C Performance Plus...

I found rust and water around the bottom of the evaporator where the metering device connects in to it. maybe a blocked drain line???