High AC current draw

[2edgesword]

There is a device you can use to tap into a sealed unit. So yes, even in a sealed unit you can add refrigerant.

Giving the repairman the benefit of the doubt he may have found based on his experience that sniffing, finding and repairing the leak in most cases isn't cost effective so he recommends using stop leak and adding refrigerant.

[Volusiacrazy]

I personally know the people that own the camper sales and recommended the repairman to look at it . They are a very reputable shop and wouldn't recommend someone that they use if they didn't do a decent job. I just think the AC had problems.

[nynethead]

The ac draws 21-22 amps on start up. Once running it may reduce draw

[FrankD]

Originally Posted by kblast523

After removing I disassembled the unit and found the evap coil was totally matted and about 60% blocked. The condenser coil was also dirty. Bottom line, refrigerant would not have helped. Cleaning the unit is the remedy.

FWIW


If the high amp draw was present before the repairman, this would be where I would start looking for a high amp draw. Either the evap coil is blocked to airflow or the condenser coil has one or more tubes collapsed internally. This can be tested with a good temp probe (not infrared). What you need to see is a 30 degree drop from the inlet to the outlet on the condenser after it stabilizes a few minutes.

If the high amp draw was after the repairman, then suspect an overcharged system.

Unfortunately some of the replies relevant to low supply voltage are wrong. In a properly running system the START and RUN capacitors perform the functions of their names. IE the Start Cap would supply the compressor startup voltage of say 200 to 500 vAC. Here is how the math works;

Voltage = Amps x Resistance

normal system; 120vAC / 15 Amps = 8 Ohms Resistance

If you decrease the input voltage to 100vAC / R (8 Ohms) = 12.5 Amps

So you see as the supply voltage goes down, the Amp flow goes down also. When it gets to low then the Start and Run Caps cannot store enough power to supply the voltage boost to the compressor.

BTW.. there are some new Caps that can compensate further than stock ones and are engineered for both spikes and brownouts. They are not usually expensive and require limited skills to install.

[saarf]

Have you measured the camper voltage during different parts of the day with the A/C unit on and off? If you see a big drop a Hughes Autoformer may help.

https://www.campingworld.com/hughes-...SABEgIE7fD_BwE

I have this unit and it does help keep the voltage at a acceptable level. It will not give you more current! My 5th wheel is 50 Amp input but the campground only has 30a therefore this 30 Amp model works for me.
By the way, Camping World is cheaper than Amazon. No surprise!

[Dustdevil]

Originally Posted by FrankD

FWIW



Unfortunately some of the replies relevant to low supply voltage are wrong. In a properly running system the START and RUN capacitors perform the functions of their names. IE the Start Cap would supply the compressor startup voltage of say 200 to 500 vAC. Here is how the math works;

Voltage = Amps x Resistance

normal system; 120vAC / 15 Amps = 8 Ohms Resistance

If you decrease the input voltage to 100vAC / R (8 Ohms) = 12.5 Amps

So you see as the supply voltage goes down, the Amp flow goes down also. When it gets to low then the Start and Run Caps cannot store enough power to supply the voltage boost to the compressor.

BTW.. there are some new Caps that can compensate further than stock ones and are engineered for both spikes and brownouts. They are not usually expensive and require limited skills to install.

Not exactly. Ohms law describes how conductors transmit power. Does not describe what happens to an induction motor on a power source operating at low voltage. Amp draw for the fraction of a second during startup of the motor is lower than normal if line voltage is low, primarily due to resistance described in ohms law. But in continuous operation, an induction motor operating at, just to pick a number, 10% lower than normal voltage, will draw approximately 10% more current to compensate. It still requires the same total power, and if it cannot get full voltage, it will draw more amperage. They also operate less efficiently, and this, coupled with higher current, are the reasons motors often run hot and fail due to low voltage. Capacitors extend the amount of time the motor can draw full starting current without an accompanying sag in voltage. But they don’t affect the continuous current draw of an induction motor under load in any appreciable way.

[Volusiacrazy]

Originally Posted by saarf

Have you measured the camper voltage during different parts of the day with the A/C unit on and off? If you see a big drop a Hughes Autoformer may help.

https://www.campingworld.com/hughes-...SABEgIE7fD_BwE

I have this unit and it does help keep the voltage at a acceptable level. It will not give you more current! My 5th wheel is 50 Amp input but the campground only has 30a therefore this 30 Amp model works for me.
By the way, Camping World is cheaper than Amazon. No surprise!

The voltage was around 115 when the current draw was high.

[Red Peters]

I was a service manager in the AC business for a very large contractor for 44 years. I know refrigeration inside and out. Stop leak is a contaminant...period. The systems for RV's are very small, sealed systems and should never need additional refrigerant unless the system is ruptured somehow and then, it would be a major repair. There is only one way to get the correct amount of charge into your system and, from what you told us he did not have a clue. First you would install a pair of access valves. One in the suction side and the other in the high pressure side. Next you recover any remaining refrigerant, however, if there were a rupture there would not be any left plus, EPA section 608 of the clean air act does not require small sealed systems to have to be recovered in the event of a leak.......dumb right? Anyway, I would never ever allow a tech to take a set of gauges and a bottle of refrigerant up on the roof first. For these small systems a visual inspection of both the evaporator and condenser coils to see if they are clean is where you start.......maybe he did that, I don't know. If they are dirty clean them. The next thing is the verify the temperature drop across the evaporator coil. This will tell you if the refrigerant system is operating right or not....period. A typical unit should give a temperature drop of 16 to 20 degrees F across the evaporator coil. It's very easy. Measure the return air temp going in the the evaporator coil and then the discharge temp coming out. The difference is your temperature drop or "Delta T". If that is within the range indicated you are good to go. Look for some other reason for high amp draw and cooling problems. If the drop is less then, again, make sure both coils are very clean and that there are no restrictions like closed off return air grills or discharge air diffusers.

This is long so I'll end it up......if anyone tries to add refrigerant to your self contained system you should first question the heck out of them. They should have found a rupture or worn area when the metal wore from vibrating against something. If that is the case you have the opportunity to make the decision as to whether or not to replace the unit. Remember, these 15k units only cost the dealer from $750 to around a grand at the most..........You can probably buy one all day long yourself for that range. Most honest RV repairmen would be up front and not try to tell you they are adding refrigerant and, there is no reason at all to ever add stop leak in one of these small units.........all it does is plug up the tiny orifices that meter refrigerant as it goes into the evaporator.......bad idea. Sorry for being so long but it just ticks me off to see these so called repairmen charge people when they don't know what they are doing........

[peonu2]

Originally Posted by Volusiacrazy

As much as I hate to think about it, I think the best thing to do would be to replace the whole thing with a new unit and be done with it. I paid that guy $180.00 so I think a new unit is the way to go. Thanks for all the replies.

hi i have been a ac repair for 40 years and yes he should have not tryed to stop leak it. make sure the condenser and evaporator are clean he may have put too much in it and the head pressure is too high. i think before you go buy a new one find a reptuble one and evacuate is and properly re-chg with a scale . it only holds a small amount of freon. but be sure everything is clean hope this will help

[flyboy1]

Originally Posted by Red Peters

I was a service manager in the AC business for a very large contractor for 44 years. I know refrigeration inside and out. Stop leak is a contaminant...period. The systems for RV's are very small, sealed systems and should never need additional refrigerant unless the system is ruptured somehow and then, it would be a major repair. There is only one way to get the correct amount of charge into your system and, from what you told us he did not have a clue. First you would install a pair of access valves. One in the suction side and the other in the high pressure side. Next you recover any remaining refrigerant, however, if there were a rupture there would not be any left plus, EPA section 608 of the clean air act does not require small sealed systems to have to be recovered in the event of a leak.......dumb right? Anyway, I would never ever allow a tech to take a set of gauges and a bottle of refrigerant up on the roof first. For these small systems a visual inspection of both the evaporator and condenser coils to see if they are clean is where you start.......maybe he did that, I don't know. If they are dirty clean them. The next thing is the verify the temperature drop across the evaporator coil. This will tell you if the refrigerant system is operating right or not....period. A typical unit should give a temperature drop of 16 to 20 degrees F across the evaporator coil. It's very easy. Measure the return air temp going in the the evaporator coil and then the discharge temp coming out. The difference is your temperature drop or "Delta T". If that is within the range indicated you are good to go. Look for some other reason for high amp draw and cooling problems. If the drop is less then, again, make sure both coils are very clean and that there are no restrictions like closed off return air grills or discharge air diffusers.

This is long so I'll end it up......if anyone tries to add refrigerant to your self contained system you should first question the heck out of them. They should have found a rupture or worn area when the metal wore from vibrating against something. If that is the case you have the opportunity to make the decision as to whether or not to replace the unit. Remember, these 15k units only cost the dealer from $750 to around a grand at the most..........You can probably buy one all day long yourself for that range. Most honest RV repairmen would be up front and not try to tell you they are adding refrigerant and, there is no reason at all to ever add stop leak in one of these small units.........all it does is plug up the tiny orifices that meter refrigerant as it goes into the evaporator.......bad idea. Sorry for being so long but it just ticks me off to see these so called repairmen charge people when they don't know what they are doing........

Red; I do have a question that I hope you can help me with. In Las Vegas a couple months and use the air on my new 2018 Eagle. This was the first time it was used. Day 1 air ran and ran and cooled well. Day 2, turned on the air and it ran and ran and wouldn't cool. After a lot of frustration trying to get some service I climbed on the roof and took the cover off and exposed the unit. What I discovered was a frozen up unit. I used a hair dryer along with the sun to thaw and dry the unit. Reassembled the unit and turned it on, it ran fine for the remainder of our stay. So my question, why would the air freeze up? Not being a refrigeration person I have no clue why they freeze up. Any information would be helpful and thanks in advance.

[wags999]

Originally Posted by flyboy1

Red; I do have a question that I hope you can help me with. In Las Vegas a couple months and use the air on my new 2018 Eagle. This was the first time it was used. Day 1 air ran and ran and cooled well. Day 2, turned on the air and it ran and ran and wouldn't cool. After a lot of frustration trying to get some service I climbed on the roof and took the cover off and exposed the unit. What I discovered was a frozen up unit. I used a hair dryer along with the sun to thaw and dry the unit. Reassembled the unit and turned it on, it ran fine for the remainder of our stay. So my question, why would the air freeze up? Not being a refrigeration person I have no clue why they freeze up. Any information would be helpful and thanks in advance.

Run your fan on high...moves more air and removes the humidity (condensation) before it can freeze... low air movement will allow moisture to condensate and freeze blocking air movement.

[Dustdevil]

Originally Posted by wags999

Run your fan on high...moves more air and removes the humidity (condensation) before it can freeze... low air movement will allow moisture to condensate and freeze blocking air movement.

Yep. If the warm air is moving through the chilling section evaporator too slowly, the water vapor in the air condenses, hits the chilled metal, then freezes instantly, builds up, until it blocks off the air flow almost entirely. This can be because of a slow fan speed, too many deflectors installed in the outlets inside the RV, or it can be because the thermostat on your evaporator coils that is supposed to cycle the compressor is not making contact, and the compressor is working full time instead of cycling. The liquid and gases inside the evaporator coils become super-chilled, and freeze up even hot air coming into the unit. That's what was happening to my old AC in my former trailer. The thermostat was sitting on corroded metal, which insulated it, and it couldn't tell when the coil was too cold, hence keeping the compressor running too long.

[norty1]

On an rv air conditioner the thermostat he refers to is a small conductor with a single wire attached. It slips into the evaporator coil just above the bottom of the coil and the fins and is usually just held in place by friction. If it's hanging loose, it should be gently pushed back in place in contact with the coils.

If your remove the inside grill, you can see the wire sticking into the coil.

Correct me ac professionals if this is not correct!

[Dustdevil]

Originally Posted by norty1

On an rv air conditioner the thermostat he refers to is a small conductor with a single wire attached. It slips into the evaporator coil just above the bottom of the coil and the fins and is usually just held in place by friction. If it's hanging loose, it should be gently pushed back in place in contact with the coils.

If your remove the inside grill, you can see the wire sticking into the coil.

Correct me ac professionals if this is not correct!

I see how this can be confused with the wall thermostat. That one wasn't my problem, I was referring to one mounted up inside the AC housing in the ceiling, accessed from the inside of the RV. I believe the proper term would be thermocouple. I think they can come in different forms and different mountings, but mine on the old Dometic Duo Therm was held by a galvanized or zinc coated bracket that sort of snapped over one of the tubes in the evaporator coil up inside the AC unit. They could come unattached, but mine simply corroded between the bracket and the tube, and the corrosion insulated the connection sufficiently that the thermocouple could not properly sense the low temperature limit. And yes, the thermocouple is a cylindrical device with a copper wire attached to it. I believe its insulation was a woven fabric tube, probably a nylon or similar material. The condensation on the tubes actually caused the corrosion, which is why it took about a year for it to come back. The first time I fixed it, I took the bracket off the tube and cleaned both the tube and the bracket where it touches the tube. After that, all it took was a little wiggle to dislodge the new corrosion, and it worked fine each time. It was a good AC unit aside from that, and cooled the toy hauler amazingly well, even in 110-115 degree temps, as long as we insulated the windows with Reflectix material.

[Jeff Evans]

Originally Posted by Volusiacrazy

Hello fellow Jayco owners. I recently had a repairman put stop leak and refrigerant in my AC. It's supposed to have a amp draw around 15 amp, but when it's hot outside during the day it will draw around 22 amps and trip the breaker , then when the sun goes down it will pull the right amps and run good. Anyone know why it does this ?

It sounds like the repairman May have overcharged your A/C. I’d have it checked out by someone who would check for the leak and repair it then check the charge. I also wonder if the repairman used the right refrigerate.
Best wishes