So last week the HVAC company came by to do the semi-annual inspection of our system (we're members of their service club, so the fall and spring inspections are free) and (unsurprisingly) found issues that they recommended us fixing. Several small and inexpensive things were no-brainers to have done, but after doing some quick searching found that one of the more expensive (installing a UV sanitizing light above the condenser coils) was fairly simple to install and like 1/10th what they quoted to install it decided to hold off and research the things they found regarding the A/C compressor: replacing the contactor as it is apparently near the end of its life, and installing a 'hard start' compressor saver kit since the unit was showing about 5% higher of a draw on start than the specs for the compressor allowed for.
The A/C company's quote to install both was a bit over $700, which isn't terrible compared to replacing the compressor. But- I can also get both a new contactor and a 'hard start' kit from Amazon for under $50... but I'd have to install them myself, and would have the risk that if I screwed something up that I could toast the compressor and have to pay a whole lot more to have it replaced.
Both the contactor and the hard start kit appear to come with instructions, and there are a number of reviews stating that they're easy to install. I'm pretty confident I can replace the contactor and install the kit- I've done a good bit of electrical work around the house over the years- but the specter of a several thousand-dollar compressor replacement worries me.
Anyone here have any prior experience with things like this? Would you spend the extra $600 for the piece of mind that installing them yourself wouldn't run the risk of costing several times that if you screwed up?
Noddaz
PowerDork
3/26/24 5:59 p.m.
Is the compressor and contactor covered even if you do not do the update?
If so, let it ride. It sounds like an upsell for something you may not need because it would be covered in your service contract.
11GTCS
SuperDork
3/26/24 8:37 p.m.
In reply to Ashyukun (Robert) :
How old is your system? What refrigerant does it use? That will matter in terms of how much you will want to put into the system. If it's more than 20 years old or uses R-22 or both I would run it as is or fix it yourself and budget to replace your system in the next few years.
The average 3 ton outdoor condensing unit uses a 2 pole / 40 amp contactor with a 24 volt coil. The part might cost $40.00, the contactor in the unit should have markings with the actual amp rating and coil voltage. If you shut the power off, take a picture of the wiring and swap everything back it might be a 10 minute job at most. The slight amperage rise they mention on start up could be due to worn contacts, I would change the contactor before adding a hard start kit.
I'm honestly wondering how they got any accurate readings unless it was 80 plus degrees outside when they did the inspection.
A contactor is dead simple to change. I keep an extra on hand at all times for my system. Fire ants here in Texas can get into them and cause the contacts to arc, so changing them is pretty common. Just pull the disconnect to kill the high voltage and turn the thermostat to "off" to kill the 24v and change it wire for wire with the new one. Ten minutes.
Hard start kits will come with instructions. It's just three wires. Easy to do while you're doing the contactor and have the panel off the unit.
When I did HVAC work a few years ago we paid something like 25 bucks for a contactor and about 60 for a quality hard start kit. Now that I'm out of the business I just get my stuff from SupplyHouse.com.
Our older Carrier Unit (installed 2001) wouldn't start and I watched the service guy check and clean the contactor in it. An earwig had gotten fried between the contacts and his carbonized corpse prevented the contacts from closing. Used to happen every spring. I would pull the disconnect and do it myself. After a few years, the contacts were pretty badly pitted and I changed out the contactor. I've done a couple since. Not a bad job. Take a picture before you pull the wires so you can't screw it up. Also buy the correct contactor.
What is the contactor? Is it the capacitor?
Slippery said:
What is the contactor? Is it the capacitor?
It's the relay that controls the 240v power to the compressor and the fan motor.
Went out to the garage and got some pictures of my stash
Capacitor on the left. Contactor on the right
obviously I like to be prepared for breakdowns. With a spare contactor and a spare capacitor on hand a fellow has better than even odds of getting his unit back up and running.
Cousin_Eddie (Forum Supporter) said:
Slippery said:
What is the contactor? Is it the capacitor?
It's the relay that controls the 240v power to the compressor and the fan motor.
Thanks! Being in Fl I like to be ready. I have a spare capacitor but will now get a contactor, just need to check what my unit uses.
Cousin_Eddie (Forum Supporter) said:
A contactor is dead simple to change. I keep an extra on hand at all times for my system. Fire ants here in Texas can get into them and cause the contacts to arc, so changing them is pretty common. Just pull the disconnect to kill the high voltage and turn the thermostat to "off" to kill the 24v and change it wire for wire with the new one. Ten minutes.
Hard start kits will come with instructions. It's just three wires. Easy to do while you're doing the contactor and have the panel off the unit.
When I did HVAC work a few years ago we paid something like 25 bucks for a contactor and about 60 for a quality hard start kit. Now that I'm out of the business I just get my stuff from SupplyHouse.com.
Thanks, that's really helpful! It sounds like if I'm careful and follow the instructions it shouldn't be too difficult. Good idea on picking up a spare contactor- we've not had bugs kill a contactor, but they did take out the capacitor a year or so ago so I may take note of the info on that when I install the contactor & hard start kit and pick up a spare of it as well since that was a several hundred dollar replacement.
Any recommendations for 'quality' brands? Amazon has a Carrier contactor (24VAC 30 Amp Coil Single Pole) that was what I was thinking of going with (my employer used to be owned by the same parent company as Carrier, so I'm partial to them), but none of the hard start kits are from any company I recognize (and honestly they look like they're all the same parts anyway).
In reply to Noddaz :
There isn't a service contract per se on the HVAC, they have a 'club' membership you can buy that gets you free biannual inspections and 10% off all parts & services- it costs just slightly less than what it would cost to pay for them to do the inspections so it makes it worth it for us (and ensures that we don't just forget about it since they call and remind us). So if something happened to the compressor- be it from my berking something up or something failing on its own- it would cost the same amount for us to have them replace it.
In reply to 11GTCS :
The system is about 11-12 years old- our house was renovated/flipped before we bought it 10 years ago and they put in an entirely new HVAC system (and IMO didn't do the best of job in some respects- the house is just too big/has too many floors for just one unit to properly heat/cool all of it evenly), so it shouldn't be running R-22. According to their quote it's a 24VAC 30 Amp Coil Single Pole contactor. I wasn't watching the guy do the inspection, but it was an unseasonably warm day. IIRC (and my memory isn't always the best) he said that he measured it at 117 amps and the spec was 110 amps.
Given the hard start kit is pretty cheap, I figure if I swap the contactor myself (which I'm leaning heavily toward) I may as well just install a hard start kit at the same time since I'll have it open and the system powered down.
If you are on this board, chances are you will be fine to replace the contactor and capacitor.
It might bear mentioning that capacitors of this voltage and capacitance can give you a hefty shock. Discharge before handling!
Noddaz
PowerDork
3/27/24 3:26 p.m.
In reply to 1988RedT2 :
Interesting video. Thank you. Capacitors still scare me.
Ashyukun (Robert) said:
In reply to Noddaz :
There isn't a service contract per se on the HVAC, they have a 'club' membership you can buy that gets you free biannual inspections and 10% off all parts & services- it costs just slightly less than what it would cost to pay for them to do the inspections so it makes it worth it for us (and ensures that we don't just forget about it since they call and remind us). So if something happened to the compressor- be it from my berking something up or something failing on its own- it would cost the same amount for us to have them replace it.
We have the same kind of thing with a company here. The "service membership" free inspections and tweaks to settings if need be, replace the filters and the 10% off parts/labor AND no after hours additional labor costs.
It already paid for itself a few years ago. I don't remember what it was that failed, but you don't really care when it only costs $80 to get your A/C working in June in Oklahoma the next day vs waiting days or having to pay a lot more.
[hijack]
Can someone explain to me why you would want or need a sterilizing UV light for the condenser?
[/hijack]
In reply to Curtis73 (Forum Supporter) :
Thanks. I was afraid to ask.
Curtis73 (Forum Supporter) said:
[hijack]
Can someone explain to me why you would want or need a sterilizing UV light for the condenser?
[/hijack]
My guess is that due to the constant presence of condensate in the summer, this area could be a good place for mold to grow.
Edit: Ooops! Should be at the evaporator coil.
https://www.hvac.com/expert-advice/hvac-uv-lights-do-they-work-and-are-they-worth-it/
Seems most of the responses are spot on.
5% overage on amp draw could be a few things but I wouldnt spend serious money to fix it.
Remember that V equals IR and all that jazz. If resistance goes up, voltage goes down. Since you still are doing work, current will go up accordingly.
So -
What is your incoming voltage? If its at the bottom of the spec everything can be fine and still see higher amp draw.
A little bit of resistance (dirty wiring, burned up contactors) will bump your amp draw up even though the system may be mechanically OK with the exception of the dirty wiring and contacts on the starter. Again. V=IR is all you gotta know.
Cousin_Eddie (Forum Supporter) said:
Went out to the garage and got some pictures of my stash
Capacitor on the left. Contactor on the right
obviously I like to be prepared for breakdowns. With a spare contactor and a spare capacitor on hand a fellow has better than even odds of getting his unit back up and running.
This is the way. I also have a condenser fan motor since mine eats one regularly.
The contactor and the soft start are pretty straightforward installs. The HVAC company's prices are a little high as well. Home Depot carries the contactor for about $30. The soft start is available online for under $250.
