Testing RLA's

Hello fellow Inspectors!

My question is on RLA’s, (Run Load Amps)
Does anyone know what the range of the measured RLA’s should be compared to the data plate?

Thanks!

Dave

Generally guidelines, 60-90%, FLA too

Correct Shawn, I generally am looking for around 75%, personally I think that the +/- 15% is a bit of a wide spectrum, but 5 - 10% deviation does not bother me too much.

Regards

Gerry

Let me ask you a question why are you checking RLA what benefit does it serve.

It can show you if a compressor may be going bad. If it is pulling too many amps, there is a reason. Better to report it than get a phone call a few weeks later that the unit does not work. Its just one more little thing we can do that could save us a lot of money with little effort.

There are numerous reasons that can and do create excessive amp draw on a compressor such as a dirty condenser, Condenser fan motor rotating backwards, Condenser fan motor not running at MFG design speed or a wrong RPM fan motor installed. All of this happens. I am not stating that it is wrong to check the amp draw if you are comfortable with that. Just need to know what and where you are checking. Do you check amps at the contactor or on the compressor. You have three wires going to the compressor and not all three wires will have the same amp draw. Do You know what you are checking or are you just creating more question to have to answer for you client that they have not a clue what you are talking about.

A lot of times I will check it at the disconect. As you stated: “There are numerous reasons that can and do create excessive amp draw on a compressor such as a dirty condenser, Condenser fan motor rotating backwards, Condenser fan motor not running at MFG design speed or a wrong RPM fan motor installed”. I do not diagnose why the amperage draw is high, I just state that it needs to be repaired by a licensed air conditioning company. We are stating a condition, not the remedy.

WOW! how long do want a home inspection to last .
We could check water pressure and water flow .
We could check the voltage and see if it too high or too low.
Incidentally these things also change at different times of the Day.

I am so glad to see all the Home Inspectors before us ( This I think is in all Associations) set a sensible SOP.
When we start exceeding the SOP our liability goes up not down.
I like the system we have now and do not like the idea of 6 hour inspections .
I have enough trouble with those who charge too little .
Roy

Thats my point you stated that the COMPRESSORE was going bad based on a amp draw taken at the disconnect which gives you the amp draw of everything that draws power in the unit. Doing that you are going to get egg on your face very quick.

My report states that I am not responsible for what happens a few week down the road the minute I leave the property my liability stops.

Roy,

SOP is a minimum standard. It takes me an extra minute to take a reading. I have had too many instances where the system was charged for the inspection and it dies a couple of days later. If the unit is easily accessible, I will pull off the cover panel and inspect the wires. I cannot tell you how many times the wires are burned or corroded. I guess i got tired of hearing the AC guy say the inspector should have seen this. A little extra work goes a long way in warding off those phone calls.

Charley,

I never state that the compressor is bad, just that the reading is high, which could mean a possible problem. This way it gets deferred to a licensed air conditioning company for repair. As we both know, there are many issues which could cause a high reading. I am not diagnosing, just reporting what I see or can test easily.

What is the story with this?
When does an air-conditioning guy know anything about what a home inspector is supposed to do?

It appears to me that the HVAC contractor is operating outside of his license and is violating the home inspection laws in many states when he provides information to your client concerning home inspection. In my opinion this performing home inspection services without a license.
I’m going to test the waters on this one. Does anyone have any opinion on this?

A large majority of lawsuits against home inspectors or outside of court settlement is generated because of what a home inspector was supposed to do in accordance with an HVAC contractor. An HVAC contractor will be the first to say that a home inspector knows nothing about HVAC but they are also the first to tell the client what you the home inspector was supposed to do.

I think I will carry this thread over to the legal section and get Joe Ferry’s opinion on this, if you wish to join us.

One word of caution about using RLA/FLA (which by the way is the same thing) to evaluate operating conditions of HVAC equipment. These components are rated by the manufacturer under certain conditions. These conditions do not always exist when you are testing operating conditions of the equipment. In the case of a compressor on a cool day, the compressor has very little work to perform and even if there is a condition that would raise the amperage reading, it would be undetectable due to the weather conditions providing little load on the equipment as designed. In the case of a motor, if that motor were to be replaced and not original equipment, often a fan blade is reused and may cause a different amperage draw during use. Fan blades that have more bite than they are supposed to, may cause higher amperage draws which will not necessarily affect the motor but does give you a reading higher than the manufacturers nameplate. The same condition would apply as with the compressor if the fan blade installed on the motor has less bite than the service duty capacity of the motor is designed for and even when there is a problem it cannot be detected because the workload on the motor is reduced to start with and elevated readings cannot be detected.

When I find a motor that is leaking oil, that may not spin freely, is heavily rusted etc. I sometimes test the RLA just to see if it exceeds the manufacturers specifications. This is just further backup for noting deterioration of the component. Just because a motor seal is leaking does not mean it is “not functional”. However the motor does become “not functional” when oil leakage is apparent, overheated motor casing is detected, and/or RLA exceeds manufacturers specifications.

[quote=dandersen]
One word of caution about using RLA/FLA (which by the way is the same thing) to evaluate operating conditions of HVAC equipment.

Wow David that was some One Word.

Do you like RLA as determining factor for further evaluation or not. I personally do not to many variables.

Negative, I sometimes take the RLA for my own reference so I know how much emphasis to put on the repair/evaluation.

Yeah, my one-word often gets carried on. Like RRay, I use voice dictation and it’s easy to get carried away! :slight_smile:

Measuring and reporting the RLA is not the same as calling for an evaluation.

In our area, A/C is a huge issue. If we report the condition and document the facts, then the A/C contractor can’t tell the new owner " your home inspector should have told you xyz was bad."

If you measure all the A/C’s you encounter during the day, you will soon learn what is “normal” and what is not “normal” for each size range and type of unit. In Florida, every house has central A/C, so you get proficient quickly.

Measure the draw, report it, (good or bad, it’s just data), and if it’s too high (exceeds the mfr. data plate for example) call it out for repairs.

It is a liability control for A/C inspections.

Dom.

RLA… way to specialized for me…

Just curious have you ever found a unit that exceeded its name data for amperage draw.

Me too Justin.:smiley: Next we will be measuring furnace BTU’s in actual operating conditions.:wink:

Yes, many have had high readings. Typically older, or otherwise “challanged” units. Feedback from clients has been that the system needed expensive repairs or, sometimes, replacement.

Dom.