Also makes it safer for the scrap metal thieves that will steal your outdoor unit. Wouldn't want them to electrocute themselves and sue you and win.
Central AC - How long should I wait after turning on breaker?
- Thread starter Number_35
- Start date
Also makes it safer for the scrap metal thieves that will steal your outdoor unit. Wouldn't want them to electrocute themselves and sue you and win.
Ed, I think the entire (nominal) 240 V would apply to your power calculation, so that would be more like 140 W. That would add up fast.
I need to check the unit in a few months after it's shut down for the season. If there is a thermostatically controlled heater, it would run a lot here at -35 C. If so, I'll continue to flip the breaker off for the winter.
I wish my clamp-on meter had that low range, but can't complain - paid $11 for it quite a few years ago.
Gah! Do thieves actually go after AC units now? Are they the new catalytic convertors? The possibility had never occurred to me.
Yep… they go after the copper. Can’t speak for everyone else, but my newer York uses an all aluminum micro channel style coil vs copper tubes with aluminum fins, which I hope is a deterrent.
You can open the electrical wiring cover on the unit and look to see if there are two smaller gauge wires going to the compressor from the contactor. Normally there are only 3 and they are heavy-gauge wires. If there are two additional smaller (18AWG or so) wires going to the compressor then it does have a heater. You might even be able to see this looking down from the top.
They sure do.
Crankcase oil heaters are not so much to warm the oil its for driving out any refrigerant from the oil to keep it from foaming up at startup. Not all compressors have heaters need to look on the wiring diagram. And if it's a.few years old it may be bad need to check it with a clamp on amp meter. Most residential compressors are 50 watts. 4 hours when its warm out side.
https://www.acfurnaceparts.com/Service Manuals/13ACD.pdf
Per the linked document, a crankcase heater is optional.
My inspection was inconclusive - Rhino conduit containing the three power conductors (240 Vac) runs alongside a small BN cable which almost certainly carries the low-voltage (24 Vac) control conductors. The Rhino conduit enters and exits the disconnect switch on the outside wall of the house. The run of control cable is continuous.
Per Pg 12 of the linked document, the wiring to the crankcase heater (if present) is all internal - I'm not curious enough to start taking things apart to confirm the presence of a heater.
If there is a crankcase heater, it is thermostatically controlled. I will leave the breaker on this coming autumn, and check for current again. Once it gets cold out, the heater, if present, should run. This is only for my own curiosity, though.
After determining whether or not there's a crankcase heater, I'll continue to flip the breaker off after cooling is no longer required, and will turn it on again at least 24 hours before I think we'll want to run the AC.
Doing so does no harm, and might do some good.
Thanks, everyone, for your contributions.
Per the linked document, a crankcase heater is optional.
My inspection was inconclusive - Rhino conduit containing the three power conductors (240 Vac) runs alongside a small BN cable which almost certainly carries the low-voltage (24 Vac) control conductors. The Rhino conduit enters and exits the disconnect switch on the outside wall of the house. The run of control cable is continuous.
Per Pg 12 of the linked document, the wiring to the crankcase heater (if present) is all internal - I'm not curious enough to start taking things apart to confirm the presence of a heater.
If there is a crankcase heater, it is thermostatically controlled. I will leave the breaker on this coming autumn, and check for current again. Once it gets cold out, the heater, if present, should run. This is only for my own curiosity, though.
After determining whether or not there's a crankcase heater, I'll continue to flip the breaker off after cooling is no longer required, and will turn it on again at least 24 hours before I think we'll want to run the AC.
Doing so does no harm, and might do some good.
Thanks, everyone, for your contributions.
https://www.walmart.com/ip/Lennox-93M04-100499-01-CC-Crankcase-Heater-40W-240V-10-HEATERS/570534532
The Lennox J3M04 heater, if present, consumes 40 W - well-worth turning off during the off-season. That's almost 1 kW-hr per day, so about $3.00/month, presuming it would stay on 24/7 during the winter.
The Lennox J3M04 heater, if present, consumes 40 W - well-worth turning off during the off-season. That's almost 1 kW-hr per day, so about $3.00/month, presuming it would stay on 24/7 during the winter.
If you can see the compressor through the top of the unit, the crankcase heater will look like a big hose clamp around the compressor.
Attachments
Similar threads
