One of my instructors in school told me that

[JumpMan23]

about 70%-75% of the problems in the field will be electrical. Is this a pretty accurate statement?

[beenthere]

Pretty much so.

[rickboggs]

I would say an equal amount is airflow

[dandyme]

at least 90% of failures will be related to something made in china, mexico, pakistan------in newer equipment

[Roddy73]

As far as what you are learning in school I would say that's a good way of thinking about it. Airflow, pressures, cleaning etc can be learned with experience easier than electrical troubleshooting can.

Become a ninja with your multi-meter and a skematic and you'll always be the last one layed off.:grin2:

[ACFIXR]

about 70%-75% of the problems in the field will be electrical. Is this a pretty accurate statement?

Yes, because they are the obvious ones that keep the system from even operating. But in reality you can't "see" the real problems of "airflow" and "refrigerant charge" which is the real problem in hvac. Become a "Ninja" in these areas and , well who knows how far you can go.

[iraqveteran]

And then use your newly formed Ninja skills to transform yourself into a Spider Monkey...


You'll need this skill set to get to some of the equipment.

[timebuilder]

Oh, no. It's a higher percentage than that, other than deferred maintenance.

In a typical season of cooling maybe 5% of my service calls reveal a leak of refrigerant, or a coil that needs cleaning. Compressor failures are an open or grounded winding, fan motors are an electrical failure, as are control boards, contactors, t stat wire, etc. Once in a great while I'll find a restricted dryer or orifice header, or a simple leak. When it comes to ductwork in commercial retail, virtually no company will pay a contractor to do anything more than wrap a duct with insulation, or reconnect flex that has come loose from a diffuser.

Electrical is where its at, and for many techs, it is their greatest adversary.

[timebuilder]

Get yourself on track for pro membership, because there is a lot of material in the educational forums that will help you.

[karsthuntr]

Install related problems rank up there pretty high too.

[SoFlaDave]

I would agree with that. Maybe even higher. In summer, bad capacitors alone account for about 70% of my no cooling calls. The rest is made up of drain/maintenance issues and then refrigerant loss after that. Duct issues that need immediate attention are pretty rare in my area. Most customers will live with duct deficiencies before they'll pay to have it fixed.

[JumpMan23]

Get yourself on track for pro membership, because there is a lot of material in the educational forums that will help you.

I would like a pro membership but it seems like you need to provide proof that you're currently working in the field? I may be wrong. the educational forums seems like a great place to gain some more knowledge.

[flange]

most of the rest of the problem is financial, cheap owners who dont want to fix their stuff properly. mechanical breakdown is five percent.

[midhvac]

I would say an equal amount is airflow

Ditto. The more you understand the effect poor airflow has on system components, the more you'll start to agree. Compressors, fan motors, capacitors, etc. are a few electrical components that get whipped by poor airflow.

[timebuilder]

Ditto. The more you understand the effect poor airflow has on system components, the more you'll start to agree. Compressors, fan motors, capacitors, etc. are a few electrical components that get whipped by poor airflow.

As long as the kind of work you are permitted to diagnose AND charge for includes airflow problems beyond the most simple things like clean coils and proper fan blades, yes, airflow will be of importance.

Will it (an airflow issue) be the basis of a typical service call in cooling season?

Probably not.

[rickboggs]

Service check today
Over charge in the heat mode
Under charge in the cool mode
2.5 ton Goodman
24x10 filter grille
Total external static .7
What's the problem?

[SoFlaDave]

Service check today
Over charge in the heat mode
Under charge in the cool mode
2.5 ton Goodman
24x10 filter grille
Total external static .7
What's the problem?

Holy High Static Batman.

Needs more return.

I think if I dealt with heat pumps on a daily basis I might see more issues like this but I'm way to far south.

[amickracing]

Around 30% of the problems you'll run into are user error, aka the person attempting to make it run.
Around 30% of the problems will be related to design flaws from when it was put in.
Around 30% of the problem will be from cheap poorly made parts
Around 30% of the problems will be air flow from something other than improper maintenance or installation.
And lastly, around 30% of the problem could be math errors

[GT Jets]

Around 30% of the problems you'll run into are user error, aka the person attempting to make it run.
Around 30% of the problems will be related to design flaws from when it was put in.
Around 30% of the problem will be from cheap poorly made parts
Around 30% of the problems will be air flow from something other than improper maintenance or installation.
And lastly, around 30% of the problem could be math errors


:LOL:

IMHO, if you get to work on properly maintained and installed equipment (read; commercial/industrial) then I would say closer to 90%.

If you are working on hacked in residential stuff that is fix on "crap, it don't work" then I would say closer to 30% electrical and the rest catching up on maintenance...LOL...


Good statement though. :yes:

These "generalities" made by instructors need to be taken with a grain of salt, mainly because different areas and economies will see different problems.

For an example, I have an account that has it's main building right on the beach, the numero uno problem is disappearing equipment from rust and corrosion.:Faint:

GT

[lynn comstock]

Around 30% of the problems you'll run into are user error, aka the person attempting to make it run.
Around 30% of the problems will be related to design flaws from when it was put in. Make that 60% (installation design or workmanship)
Around 30% of the problem will be from cheap poorly made parts
Around 30% of the problems will be air flow from something other than improper maintenance or installation.
And lastly, around 30% of the problem could be math errors


Also Add 30% (neglect...no maintenance)

[beenthere]

I would like a pro membership but it seems like you need to provide proof that you're currently working in the field? I may be wrong. the educational forums seems like a great place to gain some more knowledge.

HVAC/R Students can become pro members.

[timebuilder]

Around 30% of the problems you'll run into are user error, aka the person attempting to make it run.
Around 30% of the problems will be related to design flaws from when it was put in.
Around 30% of the problem will be from cheap poorly made parts
Around 30% of the problems will be air flow from something other than improper maintenance or installation.
And lastly, around 30% of the problem could be math errors

That's pretty funny!

[timebuilder]

Service check today
Over charge in the heat mode
Under charge in the cool mode
2.5 ton Goodman
24x10 filter grille
Total external static .7
What's the problem?

Sounds like a residential problem, Lol!!!

[lynn comstock]

:yes:
Service check today
Over charge in the heat mode
Under charge in the cool mode
2.5 ton Goodman
24x10 filter grille
Total external static .7
What's the problem?What problem? This is nomal. ;)
Residential, yes. Commercial units are much bigger.

[JumpMan23]

HVAC/R Students can become pro members.

Cool, I'll get on that when I have enough posts then.

[midhvac]

Will it (an airflow issue) be the basis of a typical service call in cooling season?

Probably not.

I replace lots of blower motors in the cooling season. Most die due to bearing failure from not enough air moving across them. Or not enough air moved causing the coil to ice up and pour water down into the motor.
Replace quite a few control boards for that same reason.
And quite a few complaints where the overly restrictive filter kills the airflow to the upper floor.
And I often see totally plugged filters that result in a "won't keep up" complaint.
Yes, I'd say that would be the basis of a typical service call during the cooling season, just as the airflow through a dirty condenser would be.

[timebuilder]

I'm talking "big picture" here. A blower motor failure is an electrical failure.

On a roof, a frozen coil is often an airflow issue, but the motor isn't below the coil, lol!

Sounds like it would be an issue in first-time residential calls. All our calls are by contract, and no residential at all.

So, to sum up: in an environment of maintained equipment, the vast majority of service calls will be electrical in nature.

[pdrake65]

I'm talking "big picture" here. A blower motor failure is an electrical failure.

On a roof, a frozen coil is often an airflow issue, but the motor isn't below the coil, lol!

Sounds like it would be an issue in first-time residential calls. All our calls are by contract, and no residential at all.

So, to sum up: in an environment of maintained equipment, the vast majority of service calls will be electrical in nature.

:ditto: IF maintained. Too many customers looking for the cheap way out lately and trying to do PM on their own. From what I have been seeing ,not doing a very good job of it...if at all!

[midhvac]

I'm talking "big picture" here. A blower motor failure is an electrical failure.

On a roof, a frozen coil is often an airflow issue, but the motor isn't below the coil, lol!

Sounds like it would be an issue in first-time residential calls. All our calls are by contract, and no residential at all.

So, to sum up: in an environment of maintained equipment, the vast majority of service calls will be electrical in nature.

Funny how we all think of things as they are in our own little corner of the world. :) IMO like even in resi, you see a lot of scenarios like counterflows and horizontals where no water would go down into the motor either. But 99% of what I see are upflows. Used to do about 50% commercial, but not any more.

[genduct]

I heard a good observation several years back from one of the top trainers for ICP ( Phil R.) who said: " 75% of the problems are AIRFLOW which give a Mechanical Symptom, To which the Tech tries to apply an ELECTRICAL SOLUTION!!!!!

The Nate group will tell you that the Air Distribution and Electrical questions are tied for lack of understanding. So I guess the schools are teaching the refrigeration cycle but not going deep enough in the areas that seem to have the most problems.

[timebuilder]

Funny how we all think of things as they are in our own little corner of the world. :) IMO like even in resi, you see a lot of scenarios like counterflows and horizontals where no water would go down into the motor either. But 99% of what I see are upflows. Used to do about 50% commercial, but not any more.

I know what you mean. People keep telling me I should go into residential, but I don't think I want to have to interact with the folks that write the check.

Using your example, the tech would have to determine if there was power going to that wet motor, and if there was an issue with the board, so I will opine that it is still an electrical issue, brought on by a lack of maintenance. :angel:

[timebuilder]

I heard a good observation several years back from one of the top trainers for ICP ( Phil R.) who said: " 75% of the problems are AIRFLOW which give a Mechanical Symptom, To which the Tech tries to apply an ELECTRICAL SOLUTION!!!!!

The Nate group will tell you that the Air Distribution and Electrical questions are tied for lack of understanding. So I guess the schools are teaching the refrigeration cycle but not going deep enough in the areas that seem to have the most problems.

I would love to have him try to explain that one to me.

Especially coming from a guy who works for ICP. That's almost funny, when you think about it.

[ACFIXR]

I would love to have him try to explain that one to me.

75% of the problems are AIRFLOW which give a Mechanical Symptom, To which the Tech tries to apply an ELECTRICAL SOLUTION!!!!!



Especially coming from a guy who works for ICP. That's almost funny, when you think about it.

1. Compressors short to ground- Typically why?

2. Another scenario- what do most tech's "really" adjust
refrigerant charge to? And it's typically an assumption.

3. What is the "real" capacity of a compressor mostly dependant on?

4. What is the #1 activity on any hvac equipment related to?

5. We all have seen "pristine" systems. What did they have in common in
your opinion?


OK, so most repairs are probably cap related. electrical yes.