Absolutely if there is not enough heat to absorb because the indoor temp has dropped down way too low. However if the temp inside remains the same due to a high heat load then no it shouldnt freeze. If it freezes, that means that you likely have a low indoor airflow problem.
Why go to college when you can watch this guy's channel? Haha. Watch the adds, like, comment, subscribe, whatever you can do to help him out. Lord knows he's helping us. 👌
Easy as it should be. Craig, do you have an indepth video on liquid line restriction, causes and how to diagnose it. Why will half of the evaporator core freeze for liquid line restrictions instead of entire coil?
@@electricboogie709 before the refigerant would have reached the exit of the evaporator core it must have frozen completely due to very low pressure resulting in lower temperature below freezing point, thus not enough refigerant to pass completely through the system, this is also dependent on the level of restrictions caused by the orifice. I seem to get it clearer now. Thank you Boogie et Craig
@@gpsfleetmatic not quite, the refrigerant won't ever freeze, only the moisture in the air will freeze onto the coils surface and the distributor tubing. Only part of the evap freezes because the coil is starved of refrigerant which is what is making the pressure low and in turn the temp below freezing on the coils surface. Assuming proper load on the evap, the refrigerant will still boil off into a superheated vapor as it works its way up the coil which will leave the coils surface at that portion above the freezing point of water. If you had a starved coil as well as improper load,the whole thing would be frozen. But this partial freezing will only take place on this design of coil where the refrigerant feeds into one side and exits the opposite,bottom to top, some other designs the whole coil will freeze in both situations but maybe only on the air inlet side so it's always best to let your SH and SC tell you what the culprit is.
Hi Craig, great video, thanks! Would you be willing to take a guess at how many compressors are permanently damaged due to liquid slugging as a result of a failed indoor blower motor / cap. while the system continues to “compress” liquid? I don’t have a clue personally but would be interested in your educated opinion. Thanks!
I got a mini split with a capillary tube metering device, and when I charge the system the suction pressure (and only suction) will stop at about 45-50 psi (R22) where the saturation temp is about -5C. It doesn't matter how much refrigerant I add after this, the pressure will not go up even if I end up putting in more refrigerant than what it says on the name plate (basically an overcharge). So I end up just stopping when the AC works reasonably well and not freeze the coil.
Thank you. I have a liquid line restriction issue. Now I can speak to my AC guy and tell him quit screwing me over your fired. My guy has been leading me from one thing to another charging me a fortune. Today he said its a leak I need a new Furness but he never perform a pressure test.
Great video. My suction line is frosting up. Indoor temperature is 75F and outdoor ambient is 70F. It's r410a with low suction pressure. The low side saturation temp is 28F. I am getting low superheat but normal subcooling with fixed orifice. Filter is clean and air flow is good. The coil has no frost but frosting just before service valve at outdoor condenser. All amp draws are good. I tried adding some refrigerant but the low side pressure would not rise. I just can't figure this one out. Any help would be greatly appreciated. Thank you.
WOW, that was comprehensive. There was alot of water in the pan below my coil and it was not draining - which it should. I sopped up all the water with a sponge and discovered that the lower part of the coil is frozen. The filter was sopping wet, so i got rid of it. It was installed 5 mos. ago, but appeared clean. I had no idea I was supposed to change them every 30-60 days. I checked the outside drain and the ground is all wet, so I don't know if it's clogged or not. I cleaned the coils inside and out before the season, so i know that is not the problem. I'm just going to leave the filter off overnight and see if the increased air flow helps defrost the coil. If not, i will call the HVAC tech and see if the TVX valve needs to be replaced.
Good video, got a question for u, My ac has two capacitor one for fan one for compressor can I put in one capacitor Com/Fan/H? Same value. Thank u Richard
I'm having an issue where the coil is freezing from the line that that's leaving the furnace. It looks like there's a leak coming from the silicone seal. Can a leak like that cause freezing?
Off topic, but you did a video a while back on p-traps. That video is SAVING me $$$. Here's why. 4 ton split 13 years old. It did NOT have a p-trap, but had a decent trickle of water coming out the PVC. I never thought much about it until I watched that video. I installed a Rectoseal trap and dropped the humidity 3-4% (46-47%) inside allowing me to turn the thermostat up 2 degrees. I now have an excellent stream of water coming out the drain! THANKS A MILLION!
Curious, is it feasible to omit the 2nd stage cooling wire on a 2 stage heat pump to get more heat capacity? example.. manJ heat=53k and cool is 29k. Using a two stage 4 ton unit would get me most of the heat and be only a about 15% oversized for cooling that's limited to the 70% stage 1.
I need help my suction line is freezing.my ac has gas I also checked for leaks there is none.my readings are good and i cleaned my ac but still ice only on the suction line.also my blower wheel is making a noise whenever my ac blade is raised up.whenever i lower it the noises stop.anyone has a sollution
Saludos te recomiendo darle a la rueda como un eje en la pantalla y buscar subtitulo. De ahí puedes escoger español. Todo lo que el dice lo escribe en la pantalla en español. Espero te haya ayudado.
Any hints on why the outdoor condenser coil ( and also looks like the compressor and tubing inside the condenser housing)....freezes in winter-mode operation "on heat" ???? Bad defrost control?....bad thermostat somewhere?.... faulty reversing valve?.....
Bravo! I kept hearing “air restriction = freezing” but this is the first time someone has said “air restriction = less phase change to vapor in the evaporator = low evaporator pressure = freezing”. I couldn’t understand why I got 62 psi readings (R-22) when I checked the low side and the chart said that was above freezing (36F from memory). A question: Is there a valid argument that the new HEPA filters restrict the air flow and that a cheaper “horsehair” filter might work better on an old system?
I bought a $20 Honeywell digital and programmable thermostat about 9 years ago. Apparently, it stopped turning the A/C blower on and the evaporator froze up. I couldn't get the fan to turn on at all. I just happened to have an exact replacement and, after I de-iced the evaporator, I got the blower to work with the newer thermostat. At least this is what I hope solved the icing problem.
I got a new furnace, and now my 16 year old A frame AC unit is freezing. The Cool fan speed is at High. I have switched my filter to the thinnest possible to increase the airflow but it's still freezing over. The furnace guy blames it on the AC A frame unit siting on the furnace and impeding the air flow. He was no help. He installed a temperature gage on the refrigerant line to stop my thermostat but forgot to connect it to a timer, so his solution is to stop my AC from working. I had an AC technician measure the Static air pressure which came out to be 1.07, way outside the manufacturing parameters, it's not even on the chart. The AC technician also said the refrigerant levels are good and we have no leeks. He said there is not enough air intake coming in. The fan sounds too loud when the AC kicks in. Could lowering the fan speed to medium help with the freezing? Do I need to add an intake vent? HELP! 🙂
I always tell people there is only 1 reason why an ac freezes. If the temperature of the coil drops below freezing. Why it would drop, there could be a few reasons.
The Vapor line at Work froze. The Filter Drier was outside. It was frozen on the Evaporator size of the Filter Drier only. The problem happened because of a Failed Blower Motor Capacitor. Thank you for your videos.
Excellent explanation of the problem. I can watch your videos for hours. Downflow system: what may cost liquid (refrigerant line) to sweat? The evaporator coil is freezing only on the lower portion of it ( not always)- according to you it's sign of liquid line restriction. Liquid line is always cold and sweating (most of the time but not always). Suction line is always warmer than liquid line.
I enjoy your videos.There is so much to learn. Your boots are much easier to follow . I'm going to college to learn to receive a certificate HVAC. I'll be buying your books hopefully soon. Again thanks
Hey y'all, I absolutely appreciate your videos very educational and I can actually follow what you're saying! Thank you so much for doing what you do! I had a question, have you had any issues with Nu-calgons product easyseal? By issue's I mean it causing clogs anywhere in the system? It guarantees it won't cause a clog but I think it may have clogged a txv on a system I did a repair on. Thank you again!
Problem: Indoor blower turns on/new filter. Turn on A/C and runs, once the A/C runs for about 20 min the indoor blower turns off for a few min (AC still running) and starts up for 30 seconds or so. The cycle continues and the AC starts to freeze.
Excellent explanation Craig question about hi flow filter, wouldn't that cause more dust to pass through and collect on the evaporator over time and cause flow issues vs a filter that traps everything however is a little more restrictive and cause air flow problems....I guess there's pro's and con's to both filters....do you want more air flow or cleaner air🤷🏿♂️
I have an interesting problem where my AC doesn't cool enough to drop the temp to say 75. It runs too long and the outside unit shuts down I assume it gets too hot. There is no freezing anywhere. The inside heat exchanger gets cold but I don't think it's getting cold enough. The filter is clean and the indoor fan is good and there seems to be plenty of air moving. The outdoor heat exchanger is not dirty. Tech is coming tomorrow
Great Video. My unit started to show water at the evaporator and shut down. Like you mentioned, it was actually my blower motor. Thanks for confirming my issue. Interesting it happened a few days after a HVAC cleaning and addition insulation around to copper tube at the condenser unit.
surprised you didn't mention the orifice on some systems .. like some come w txv some come w the fixed orifice and both can get jammed up and cause a restriction... came across a r22 low side line set was frozen all way up to the evap coil. gauges read 25 psig on low side 15p on high and this was w the evap coil frozen... had to let it all defrost so can get a better 3 min reading for low side evap coil temp then another 7 mins to check the rest. but once I disconnected hoses the low side was defrosted and I heard a hissing so the core valve possibly could of been leaking even tho it had a cap on it before and was frozen before I had a actually put hose on low side ... so was suspicious of leak w possibility of low refrigerant but once again needed thr whole unit to defrost to take the pressures while running and also replace core valves w new ones and continue to test for leaks and rule out if it is low refrigerant, check evap coil for dirt build up because did notice the return and supply grills had alot of black dirt on them which indicates the return didn't have filters in it for long time so they ran the unit w out that filter and it could possibly have lead to the evap coil getting caked up w dirt causing bad air flow and last the fixed orifice could be clogged up some how. ... will find out
I wish i did too. The best advice I was given when i couldnt solve a problem was to go out to the street, clear my head and then go back to the service call and keep trying! There were no videos to watch or answers found online or a way to search online while at the customers house!!!
How can you test the liquid line restriction or the metering device to determine the problem? And what is the procedure to replace them? De-solder or replace the entire A coil then recharge the system?
