Looking to power a window A/C - Page 1
Forum section: electronics / general

author: Pat75
author_rank: Newbie
timestamp: October 09, 2022, 10:47:36 pm
content: I'm looking to power a window AC and a fan in the summer (daytime only). The load will be under 750w . I am looking at a 1500w inverter and 5) 200w panels. Should I include a Easy Start? Is there anything else I would need?

author: Stray Electron
author_rank: Super Contributor
timestamp: October 10, 2022, 01:26:18 am
content: "Is there anything else I would need to know?" (added words)Yes. Start up current for both devices will be SEVERAL times higher than the run current. I doubt that a 1500 watt inverter will be adequate. Also most inverters don't output anything close to a true sine wave and many electronics systems (including modern AC controls) react poorly to poor AC power systems. I installed a modern Mitusubishi mini-split AC system about the same size about a year ago and IIRC the installation manual specifically warns about using inverters to power them. You can find those manuals online. I strongly suggest that you find the installation manual and the warranty for the system that you want to use and see what they say about running the system from an inverter.As far as a fan is concerned, you'd be a lot better off finding one that will run on DC and operating it directly from the panels and skipping the inverter. OTOH I don't know if anyone makes a DC powered AC system or not.I doubt that 5ea 200 W panels will be enough, once you consider the losses in the inverter and also the FACT that those panels will, AT BEST, only output 200 W under IDEAL conditions. I suggest buying one panel, installing it and running some load tests under various weather conditions, cloud conditions, season, sun angle, shading, etc etc and see exactly how much power you can realistically get from one before buying a complete system.One final comment, in the US window ACs are very poorly designed IMO and aren't very efficient. A mini-split is MUCH MORE efficient but also a lot more expensive. I have used window AC units in the past and in fact, I still have one stored away for emergency use, but I would not use one for continual use. One of my neighbors is too cheap to pay to fix her main AC and is using a window AC and it doesn't keep her house cool enough AND her electric bill is costing her over 3 times what my bill costs!

author: hubi
author_rank: Regular Contributor
timestamp: October 10, 2022, 01:42:52 am
content: I agree that a minisplit is much nicer than a window unit. If you go the DIY installation route, the prices have become pretty affordable (at least in the US). You can get a 12,000 BTU/h minisplit heat pump kit delivered for around $500 from ebay, or pick one up from the blue or orange store for around $600-$700.

author: Pat75
author_rank: Newbie
timestamp: October 10, 2022, 02:21:40 am
content: Ok, thanks for the information. That helps a lot.

author: AlbertL
author_rank: Regular Contributor
timestamp: October 11, 2022, 02:08:58 pm
content: Quote from: Stray Electron on October 10, 2022, 01:26:18 amYes, there are DC air conditioners - most seem to run on 48V (probably for the telecom market) - Google "48V DC air conditioner".