This video is brought to you by sportlin quality, integrity and tradition. All right, we've got a service called an exhaust fan not working today. Um, you can tell these. Exhaust fans certainly are dirty too.

They haven't been cleaned in a while. I'm trying to figure out which fan it is, though they're all running. Ah not this one right here, open it up and uh the wiring looks a little silly. I flipped the switch.

Nothing happened, motor spins belt's on there motor's, not hot, it's actually cold. So we're going to actually start at the motor starters, which are actually, i believe in this makeup air unit right here, so we're gon na open this up and see okay. So this is our motor starter cabinet right here, um, another notice is it's: making our units got bad bearings on the blower assembly. That's kind of a mess um, that's a whole nother thing, but this is my exhaust fan right here and we have a trip motor starter, so i turned off the switch, so i should be pretty safe, resetting this okay and uh.

Now we got to come over here and check that i don't want to turn it on. Yet i want to check the exhaust van we're going to hinge. It check the wheel, make sure nothing's stuck in it check the motor all that good stuff. So up in here, um the wheel, spins doesn't look to be anything stuck in it.

It's a little dirty but not horrible. I'm not seeing anything scary here, a quick inspection of the electrical i mean it doesn't look the greatest, but i don't see any shorts. I think we're pretty safe to try to fire this guy up see what happens: um belt's a little loose. I certainly like these ones that have the switches inside i prefer them to be a switch outside.

Also, let's look at these bearings making sure nothing's broken. I mean everything rotates huh. You know i want to do some more inspections before i turn that switch on. I want to go ahead and open it up and inspect the electrical in there, i'm not going to inspect the electrical in the motor, but i want to check in that switch all right.

This i came over here because i wasn't getting good voltage at the power switch. I didn't turn the fan on yet so, let's uh test it right here coming out of the motor starter. This should be a 208 volt circuit, so we're getting 99 volts, a to b, b to c 95 volts and a to c 203. So, let's check incoming to the motor starter.

209. 206.. 209. So we got a bad motor starter.

The problem with these ones is these are 24 volt motor starters and they're not readily available at the supply houses. I usually have to order them, so i'm going to run down to the vans. Sometimes i keep them in stock. I can't remember if i have one or not all right, i got the new motor started.

Supply house had it in stock, so that was cool and they weren't too far away. So we got a 24 volt starter, it's a little big as far as the current rating. They only had a 12 amp. I really only need a 9 amp, which is, i believe, the smallest one they make.

But it's all good. I got a new overload for the starter um. This is a 24 volt system, and so what i did was went ahead and pulled the coil voltage off so that way we could still have everything else. Running.

We're gon na go turn off power. Uh high voltage power right here and then we're gon na swap this starter out real quick shouldn't take long and then finish troubleshooting from that point forward. All right motor starter's installed power's turned back on we're gon na verify. We've got good power coming in yep.

All right, let's go ahead and check them all. That's three-phase power going to the starter, which we had good in the first place and then uh, i'm gon na go verify that the switch is off and then we'll turn this on and then check power coming out. All right confirm that power's off at the switch these guys come in a tripped position when they're brand new i've got the overload set. We're gon na hit reset okay, we're pulled in now we're gon na go verify voltage over at the power switch okay.

This is power coming to the switch a to b, 206 b to c 209, a to c 208, so we're good there we're ready to fire this up and make sure there's no other problems. Okay, i want to steer clear because i don't know how long this has been off again belt's kind of loose, but i just want to fire it up and see how it reacts. First, uh we go it's running: okay and uh. Let's i'm gon na get in here and figure out what my current draw should be and we're gon na go.

Compare it current draw should be 3.4 amps and we're under current draw, so we're looking good there. I'm leaning towards the only problem was the contacts in the motor starter had failed and when it turned on it's single, phased, essentially or ran high current and tripped the motor starter. As my thoughts, i'm letting the fan run for a little bit to make sure there's nothing else wrong, and while i'm doing that, i'm just kind of playing with this contactor and check this out. So i'm forcing it closed and uh.

Let's see the resistance across the contacts pretty high, i'm trying to get this guy apart, so i can physically see inside of it. It's pretty high uh resistance across that contact from top to bottom, so i'm gon na try to get it apart. So i can see the inside. I already got the coil out and everything.

So i get a lot of people criticizing me for changing contactors as much as i do, because i try to catch contractors when they fail, you know or when they're starting to look pitted, and i do agree that you know so it's hard to tell what's. You know the final phase of a contactor and what's almost there because pitting does happen just in normal operation too, you get black marks and burn marks and stuff in normal operation, but you know yeah, you can do voltage, drops and stuff like that. But you know when, when you have these customers that don't do proper preventative maintenance and you're trying to save emergency service calls, you just got to kind of trust your gut. Sometimes at least that's the way that i go with contactors.

I would have loved to have changed this one before it failed again. The customer doesn't pay for us to come in and do voltage drop tests and different things like that. This is one, though, that you really can't see the inside of the points. You know the normal air conditioning contactors, you can kind of get in there and see these ones are kind of enclosed, but they're, not totally sealed.

So being that this is a three-phase fan, you have to make sure that the phases didn't get crossed up because it'll still run, but it won't run in the right direction. So i also verified that it's going in a clockwise rotation and uh. That's the way. It's supposed to be on this guy, so um, where we're gon na go with.

This is uh. The conduit is in bad shape and disassembled. This isn't a metallic conduit either. I prefer metallic conduit, so we're gon na quote or give them to.

Let us replace the conduit the wiring and fix that electrical with that switch too um, but other than that that's good. For now i uh put a new belt on it too um the pulley can certainly be aligned too, but i really don't want to get too crazy with this right now, the pulleys a little bit off again i'll bring all that stuff up to them all right. We are back today. I got approval from the customer to go ahead and repair this conduit and fix this wiring.

So we started by turning off power and then getting this switch removed because we're gon na replace the conduit all the way up to here and then i'm still gon na utilize. This cord, i'm just gon na use a proper connector into the switch cover. You know make a little bit nicer. The ground wire is doing a whole lot of good, never being hooked up wow, it's kind of crazy.

So it's not too hard. I just demo everything. There's the old conduit, just get all the old stuff out. The wires were twisted up, really strong and then i'm gon na go ahead and run the new conduit get an idea where it's going to go and then i'll worry about hooking everything up and then cleaning everything up in here too, and we're going to try to Adjust that you guys can see that thing's at a pretty good angle, it's a resilient mount motor, not a fan of that but anyways, whatever okay, we're gon na test the rotation on this guy.

I'm still gon na play with the belt here, but the rotation is correct, got an arrow right. There we're going the right direction. We've got plenty of slack to hinge the fan. I've still got to clean this up.

I left those loose because i need to uh tape them up. I just wanted to check the rotation first, so we're looking good so far. We're cleaned up in here to where nothing funky is going on. Um yeah wrapping it up.

So i just got to clean up some crap and then um, oh yeah. I got ta fix that pulley yeah, then we're gon na. Do the pulley real, quick look at how far off that was. I was able to move this pulley right here down more than a quarter of an inch to line it up, so the last person that put a motor on this didn't straighten it.

So i'm gon na go ahead and tension up the belt and uh yeah. All right, the exhaust fan um, is controlled by a power switch downstairs at the hoods okay, that power switch, runs 24, volts all the way up to that motor starter cabinet, and it pulls the motor starters in and out. The purpose of the motor starter is there to catch an over current before the circuit breaker, so the motor starters, the easiest way to explain them, is they're more tailored to protect the motor before a direct short but they're looking for an over current. So let's say that a towel or or the exhaust fan is really dirty or something like that is slowing it down, and the motor is just ever so slightly to go over over current now each a different motor.

It's it's really kind of confusing to figure out how to set the over current protection device. Um. There's lots of rules of thumb, uh 10 15 using the sfa like there's so many different rules of thumb as to where to go to set the over current. I suggest leaning on the manufacturer of the motor asking them how you should set over current i've heard things from some motor manufacturers that uh you know it just can get really confusing.

So you always want to lean on the motor manufacturers and or the equipment manufacturers to figure out where to set the over current on the motors okay. So in this situation the over current was set about. I think it was 10 percent over um, and that was the factory setting. I just left it where it was with the new motor starter.

Okay, so essentially that motor starter is a contactor with an overload protection device on it and it's there to protect the motor from any bad situation. So in this situation it did its job right, because the contactor portion of the motor starter wasn't letting proper voltage go through the contactor right and therefore, when the voltage went down, the current went up. Okay and the motor starters over current protection device said hey. There's a problem here and it shut down the motor before it burnt the motor up.

Okay, that's the whole purpose of a motor starter. A circuit breaker is designed to protect your wiring, while the motor starter is designed to protect your motor okay, it's not too difficult. So motor starters fail okay, now the way that i like to look at this, what happens? Okay, so this particular motor starter every one of these exhaust fans. They don't have individual switches, they have the same switch.

Okay, one power switch down at the hood panels. They turn it on and off two times a day right. They turn it on once off once every single day for those are original from 2004.. So the duty cycle on these things i mean i'm sure they've gotten their monies out of those.

But the real question is: if that motor starter failed or the other one's going to fail too. Okay, of course, i brought that up to the customer and they don't really want to do anything about it. Yet, okay, again they're not doing preventative maintenances right now and i'm not blaming them for that. But these are the things that you got to think about.

You know, as i was editing this video, i'm looking at all those other starters and i'm like man. You know what those are going to fail tomorrow too, so in this situation, what i'm actually going to do is i'm going to go ahead and stock up on those motor starters, because i know that the other ones are going to start failing, and i was lucky This time, most of the time, my supply house doesn't have the 24 volt starters. I also want to point something else out um. These are a starter, overload, combination, okay, so you can use just the contactor portion.

You do want to use them in conjunction with the same brand, because the way that they clip together, but i'm probably going to go ahead and pick those up and keep them in the shop for an emergency. Because i have a feeling the other ones are going to fail, really quick. I also wanted to clarify something when i was talking about how i didn't get the right starter assembly from the supply house, what i actually meant - and i said that the current was 12 amps and it more or less just needed a 9 amp. What i meant by that was the contact rating on the contactor okay, so you you can buy different current ratings on the contactor, so that normally i buy motor starters for these small three-phase fans that can handle up to nine amps because they run about three to Four amps, normally okay, so i usually get a nine amp contactor uh.

In this situation they only had a 12 amp contactor, there's nothing wrong with going over on the current. It just basically gives you more meat for the the contact point. You know where they make connection where the voltage passes through okay, i wasn't over sizing the over current protection device, the over current protection device. The overload section was a four to six amp, okay, so um this one uh was the right over current protection.

It was just the contact rating on the contactor portion. Okay, so really really appreciate you guys uh watch until the end. This is awesome. It's very humbling! If you haven't already please check out my website hvacrvideos.com, we got lots of cool merch on there.

These hoodies right there are available all different sizes. We have uh women's shirts men's shirts, we have two men's shirts, we have the flag. Actually, we have two men and women. No, the women's shirts is only in the flag design.

We have men's shirts and the big picture design and the flag design hats beanies, all that good stuff. It really does help to support the channel. Okay, remember that i do live streams monday evening. 5 p.m: pacific on youtube, and then i also go live on the hvac overtime channel friday evenings with my buddies about 605 pm over on the hvac overtime channel.

Okay, i really really appreciate you guys we'll catch you on the next one.