A/c breaker tripped. Anything to check.

[mike93lx]

My first floor a/c's breaker tripped yesterday. It's a 19 year old 2.5 ton York that seems to be working fine and was checked out last summer. I reset the breaker and all seems well now, blowing lots of cold air. I checked current draw with a clamp meter and got about 11.5a on one leg and 11.8a on the other. Any concerns there?

Anything else to check or just leave it alone?

Edit for new readers: the system was replaced. See post #212 https://www.garagejournal.com/forum...-anything-to-check.498335/page-6#post-9797323

 

[Jim greengo]

Is the unit clean?

 

[mike93lx]

Is the unit clean?

Based on a quick external look, yes. It was cleaned last year mid-season, so it won't be sparkly clean, but there shouldnt be much of any build up. I'll take a closer look and give it a quick rinse out over the weekend

 

[Jim greengo]

Does it seem to be cooling while its running,do you have a set of gauges?

 

[240sxguy]

When I have had that issue, it was almost always a failing start/run cap. I'd get one ASAP. I went through one about every 2-3 years at my old house for some reason.

 

[mike93lx]

Does it seem to be cooling while its running,do you have a set of gauges?

It's blowing tons of cold air right now. 53-56 degrees at the registers.

No gauges. Never attempted any a/c work, but this is my first house with central air. Last place was window units and a mini split

 

[mike93lx]

When I have had that issue, it was almost always a failing start/run cap. I'd get one ASAP. I went through one about every 2-3 years at my old house for some reason.

Thanks.

I see two options listed by York, both are 35/5mfd and labeled "dual run". difference is 370v ($26) and 440v ($40). Do I need to open up the unit to confirm?

 

[240sxguy]

Thanks.

I see two options listed by York, both are 35/5mfd and labeled "dual run". difference is 370v ($26) and 440v ($40). Do I need to open up the unit to confirm?

You can always default to the higher voltage unit (440V), but opening it up to take a peek may save you 14 bucks. It's a laziness to cost ratio you have to consider at this point. lol. My guess is that you actually have the 370v one installed but I'd hate to lead you astray with a hipshot.

 

[mike93lx]

You can always default to the higher voltage unit (440V), but opening it up to take a peek may save you 14 bucks. It's a laziness to cost ratio you have to consider at this point. lol. My guess is that you actually have the 370v one installed but I'd hate to lead you astray with a hipshot.

Thanks. Might as well open to check. I have two identical units and a third that's smaller. I should see what the rating is on the smaller unit too to confirm if I can have one spare to cover all three

 

[bonneyman]

Everything else checking out OK leads me to think it's a condensor fan problem. When it gets hot it either it goes off on overload or the bearings seize up - both stop it from running. No condensor fan and the compressor pressure goes way up as it has no way to expel heat, so the amp draw rises till it trips the breaker. Could be the capacitor for the cond fan - that's cheap and easy to swap so do that first.
Next time it stops cooling go out to the unit if it's accessible and try spinning the cond fan with a long rod. If it's tight then the motor bearings are the issue.
Condensor fan motors cool themselves with "hot" exhaust air. Not a good situation. So they tend to go out regularly due to heat related issues. The cheapie 1.0 service factor motors everyone is using doesn't help, either. So prepare yourself for a cond motor change. Not too hard or expensive, if you're capable yourself to do it.
Back in the day I could do most any cond motor in about an hour (that was $70 labor). The motor cost me $65 wholesale - I marked it up to $135. (Adjust that for what supply line shortages are causing today). So a bit above $200 plus tax and I was out the door. (New run cap I included no charge). Though calling a service company today could cost $400-500.

 

[mike93lx]

Everything else checking out OK leads me to think it's a condensor fan problem. When it gets hot it either it goes off on overload or the bearings seize up - both stop it from running. No condensor fan and the compressor pressure goes way up as it has no way to expel heat, so the amp draw rises till it trips the breaker. Could be the capacitor for the cond fan - that's cheap and easy to swap so do that first.
Next time it stops cooling go out to the unit if it's accessible and try spinning the cond fan with a long rod. If it's tight then the motor bearings are the issue.
Condensor fan motors cool themselves with "hot" exhaust air. Not a good situation. So they tend to go out regularly due to heat related issues. The cheapie 1.0 service factor motors everyone is using doesn't help, either. So prepare yourself for a cond motor change. Not too hard or expensive, if you're capable yourself to do it.
Back in the day I could do most any cond motor in about an hour (that was $70 labor). The motor cost me $65 wholesale - I marked it up to $135. (Adjust that for what supply line shortages are causing today). So a bit above $200 plus tax and I was out the door. (New run cap I included no charge). Though calling a service company today could cost $400-500.

Thanks. As far as I can tell, they are original fans, so past end of life.

Fan motor is $145 at repair clinic, but I haven't shopped that around. A little expensive to just keep on the shelf, but I only say that because my ac is working right now...

$110 at supplyhouse.com

 

[510ebl]

Dual run Capacitors are cheap enough to keep in stock, one for each unit. Same for the circulating fan cap.

 

[bonneyman]

Dual run Capacitors are cheap enough to keep in stock, one for each unit. Same for the circulating fan cap.

Yeah, for the price of capacitors today he might as well change out the comp cap, too. Cheap insurance.

 

[mike93lx]

Yeah, for the price of capacitors today he might as well change out the comp cap, too. Cheap insurance.

Why? I get having it on hand, but changing it after one issue that may not be related?

 

[bonneyman]

Just age and heat deterioration over 19 years.

Run caps don't have any moving parts to wear out, but they basically are a "jelly-roll" type of construction with alternating layers of aluminum foil and an insulator. Old ones were filled with oil, but that contained PCB's and were banned. (Of course those lasted forever as that oil was a great insulator and heat absorber). Over time and countless charge and discharge cycles the insulation can break down and cause a short, taking out the capacitor and then killing your compressor. For a handful of bucks for the cap - and it being old - just change it out.

Plus the 440 volt caps have thicker insulation than 370 volts, to handle that higher voltage. But that also makes it more heat resistant and safer over time. I got rid of all my 370 v caps when they went full Chinese and put in 440 v caps exclusively, just to be safe.

 

[mike93lx]

Just age and heat deterioration over 19 years.

Run caps don't have any moving parts to wear out, but they basically are a "jelly-roll" type of construction with alternating layers of aluminum foil and an insulator. Old ones were filled with oil, but that contained PCB's and were banned. (Of course those lasted forever as that oil was a great insulator and heat absorber). Over time and countless charge and discharge cycles the insulation can break down and cause a short, taking out the capacitor and then killing your compressor. For a handful of bucks for the cap - and it being old - just change it out.

Plus the 440 volt caps have thicker insulation than 370 volts, to handle that higher voltage. But that also makes it more heat resistant and safer over time. I got rid of all my 370 v caps when they went full Chinese and put in 440 v caps exclusively, just to be safe.

Fair enough. I'll take a look this weekend at all of them. I've only lived in the house for a year, so they could be recent replacements,but I doubt it

 

[bonneyman]

Fair enough. I'll take a look this weekend at all of them. I've only lived in the house for a year, so they could be recent replacements,but I doubt it

It's very sad, and I hate to say it, but see if the caps say "Made in USA". If yes, then they are probably original.

 

[metlmunchr]

We bought a new house in 77 that had a GE heat pump. GE at that time had this really dumb idea of stuffing the electrical components under the top cover and surrounding the condenser fan rather than having a dedicated electrical compartment like most other mfgrs.

Unit was 6 or 7 years old and the outside temp was about 95°. My daughter comes flying into the house from the back yard, and says the air conditioner made a funny noise and started blowing ice out the top.

What actually happened was the compressor cap had swelled to close to twice its normal size without failing. The condenser fan whacked the cap shell a few times and split it open. The "ice" was about a zillion shiny pieces of chopped up mylar from the guts of the capacitor.

Replacing the cap and the condenser fan blade was nothing, but cleaning up the mess of chopped up mylar from the deck and out of the swimming pool was a major PITA.

 

[Jim greengo]

We bought a new house in 77 that had a GE heat pump. GE at that time had this really dumb idea of stuffing the electrical components under the top cover and surrounding the condenser fan rather than having a dedicated electrical compartment like most other mfgrs.

Unit was 6 or 7 years old and the outside temp was about 95°. My daughter comes flying into the house from the back yard, and says the air conditioner made a funny noise and started blowing ice out the top.

What actually happened was the compressor cap had swelled to close to twice its normal size without failing. The condenser fan whacked the cap shell a few times and split it open. The "ice" was about a zillion shiny pieces of chopped up mylar from the guts of the capacitor.

Replacing the cap and the condenser fan blade was nothing, but cleaning up the mess of chopped up mylar from the deck and out of the swimming pool was a major PITA.

I seem to remember fedders and a few others ,including trane wreck using that same idea back in the day as well.

 

[Milton Shaw]

Is there any chance of a momentary power outage that caused a short cycle to trip the breaker. Other than that the caps would be the first choice. Older units like that one didn't have the 5 minute delay the new ones have to prevent short cycling..

 

[wyliesdiesels]

When I have had that issue, it was almost always a failing start/run cap. I'd get one ASAP. I went through one about every 2-3 years at my old house for some reason.

 

[yeldogt]

Agree .... I would open them all up and give a look. They should have a uniform appearance and no black. Some units also came with soft starts as well back then. They are so cheap I would just replace both if not a duel.

I always used a small Carrier compressor in my city properties and they made an uprated model that came factory installed with the soft start.

Also -- listen to the compressor when it starts. Anything odd it maybe in need of a soft start if not installed to get some more time out of it

 

[bonneyman]

Is there any chance of a momentary power outage that caused a short cycle to trip the breaker. Other than that the caps would be the first choice. Older units like that one didn't have the 5 minute delay the new ones have to prevent short cycling..

Possible. But most homes nowadays have electronic programmable thermostats, and they typically have a circuit built in that senses blackouts and institutes a 5 minute waiting period before trying to restart the compressor. Though, if the power loss is fast enough this sensing circuit could miss it (less the 250 microseconds) so it's not foolproof.

 

[mike93lx]

Is there any chance of a momentary power outage that caused a short cycle to trip the breaker. Other than that the caps would be the first choice. Older units like that one didn't have the 5 minute delay the new ones have to prevent short cycling..

I did not notice a power flicker

 

[mike93lx]

No swelling, but rusty.

Can I use the larger cap in the smaller unit? Kind of thinking of grabbing one cap and one fan motor if they can work in any of the units

They all sound the same starting up, no weird noises.

 

[510ebl]

Not saying this is your symptom, but the condenser fan motor on mine went bad (intermittent at first) and ultimately led to the breaker tripping. Looking at the rust on yours and considering the age, investing in a new one may be prudent. 20-30 minutes or so to replace (if the fan isn’t seized to the motor) and you still have the old one for a spare. I think mine was about $125 from supply house.com

Edit: I just noticed you have a couple of different size motors, maybe someone better versed can chime in regarding the interchangeability of the 1/8hp motor and 1/12hp motor.

 

[mike93lx]

Not saying this is your symptom, but the condenser fan motor on mine went bad (intermittent at first) and ultimately led to the breaker tripping. Looking at the rust on yours and considering the age, investing in a new one may be prudent. 20-30 minutes or so to replace (if the fan isn’t seized to the motor) and you still have the old one for a spare. I think mine was about $125 from supply house.com

Edit: I just noticed you have a couple of different size motors, maybe someone better versed can chime in regarding the interchangeability of the 1/8hp motor and 1/12hp motor.

Yeah, it's two 30k units and one 18k unit. I have to imagine that a 1/8hp motor would work in the smaller one, just a little overkill.

Not super excited about throwing $500 worth of parts at these units just for the sake of it. This is the only issue I have had in a year of living here.

The fans are spinning freely as well

 

[510ebl]

A few years ago I wouldn’t consider a fan motor to be preventive maintenance or something to keep on the shelf, but with long lead times and increased costs for many parts I have adjusted my thinking somewhat.

I do keep two window air conditioners available as well, should the central air be out for a few days or longer. I never considered that either, until HVAC mechanics started booking 2-6 weeks out.

 

[mike93lx]

A few years ago I wouldn’t consider a fan motor to be preventive maintenance or something to keep on the shelf, but with long lead times and increased costs for many parts I have adjusted my thinking somewhat.

I do keep two window air conditioners available as well, should the central air be out for a few days or longer. I never considered that either, until HVAC mechanics started booking 2-6 weeks out.

I am all for a spare on the shelf, no argument. Just not three.

We at least have three zones, so I still have cooling if one fails.

 

[jar944]

I am all for a spare on the shelf, no argument. Just not three.

We at least have three zones, so I still have cooling if one fails.

Depending on your house configuration the loss of one of the three systems shouldn't be a issue.

Also was that $500 just in start and run caps?

 

[yeldogt]

I would buy the correct part for the one that tripped ... On my rentals I replaced them at 10 years. I just bought some condos and replaced the older ones and cleaned the contacts.

I would only replace a fan motor if they have a history of failing. As to spare parts -- a common fail part like a igniter for a furnance that is critical and $20 .. OK. I used to keep a universal that would fit my city properties. I have a spare one for my german boilers because they can take a week to get and it's just a question of when .... not if ... about $150 Most motors can be ordered from Supplyhouse and they show up the next day .. no reason to have unless odd and not available.

 

[bonneyman]

Luckily when I closed my business in 2016 I just put all my parts inventory in storage for home use. I've got pretty much everything I need to keep the homestead going.

I've been getting all sorts of spare parts for things around the house. These days - with supply chain shortages and all - if you don't have a part in your hand and then one goes out, you could be in a real pickle. Just had the fill valve on the new bathroom toilet start leaking. Less than a year flushing twice a day and a part goes out. Geez!

 

[bonneyman]

We bought a new house in 77 that had a GE heat pump. GE at that time had this really dumb idea of stuffing the electrical components under the top cover and surrounding the condenser fan rather than having a dedicated electrical compartment like most other mfgrs.

Oh yeah, remember that style well. Found them on apartment buildings alot. Great engineering idea, not so great out in the real world.

 

[mike93lx]

Depending on your house configuration the loss of one of the three systems shouldn't be a issue.

Also was that $500 just in start and run caps?

No. $40/unit for caps and fan motors are $110/unit.

It's one zone per floor, so we can always move around until a repair is done.

 

[yeldogt]

Oh yeah, remember that style well. Found them on apartment buildings alot. Great engineering idea, not so great out in the real world.

Were they the tall square boxes ? some had a flat fan and others raised fan shroud.

I loved the old York horizontal babies ... good story about those

 

[MongoTA]

Just want to add I appreciate the info shared on this thread. Good info that can help demystify what previously were mysteries.

 

[bonneyman]

Were they the tall square boxes ? some had a flat fan and others raised fan shroud.

I loved the old York horizontal babies ... good story about those

Pretty square profile, taller dependent on size. Kinda a light tan color IIRC. A bit to get used to, it was nice to be able to work on/replace components while standing, as they were all inside the top of the unit.

Those old York heat pumps were tough old work horses. Light blue with the red control defrost board? Easy to wire past bad components and bypass bad thermistors to get those running. I used to call them the "dumb board" units, like the old SPHC Trane heat pumps. Super simple to diagnose, solid performers.

 

[bonneyman]

Just want to add I appreciate the info shared on this thread. Good info that can help demystify what previously were mysteries.

Appreciate the thumbs up, although it's been several years since I actually had hands on units other than my own. The slew of new electronic controls and Wi-Fi stuff would give me ulcers.

 

[yeldogt]

Pretty square profile, taller dependent on size. Kinda a light tan color IIRC. A bit to get used to, it was nice to be able to work on/replace components while standing, as they were all inside the top of the unit.

Those old York heat pumps were tough old work horses. Light blue with the red control defrost board? Easy to wire past bad components and bypass bad thermistors to get those running. I used to call them the "dumb board" units, like the old SPHC Trane heat pumps. Super simple to diagnose, solid performers.

I bought a bunch (10) of used ones from a complex that had a fire. Advise of a guy that did work for us -- they went into every bungalow we did for about the first 5 years and not one of them ever missed a beat.

 

[Fly YX]

If it only happened once I wouldn’t worry about it too much. Look it over see if you find bad connections or corrosion on the wires.