diff --git a/README.md b/README.md
index ba0a30d..5c75234 100644
--- a/README.md
+++ b/README.md
@@ -288,7 +288,7 @@ And oxygen brazing with (20%+)silver+copper solder required here:
You can build your own "tube-in-tube" heat exchangers. It's not hard. Cheaper. The heat exchange efficiency is worse. Very easy soldering.
-And also you can think "I'll take old AC parts... Housing... Slightly change... A hour or two, day of work maximum, and i'll got a refrigerant<->water heat exchanger in for a penny!" This idea is obvious. That was a first thing I've tried and do not want to try it anymore. You can also try this, but remember: to achieve "not very bad" performance it'll take much more than a day and much more than few $$, even if you have unlimited access to older ACs.
+And also you can think "I'll take old AC parts... Housing... Slightly change... A hour or two, day of work maximum, and i'll got a refrigerant<->water heat exchanger in for a penny!" This idea is obvious. That was a first thing I've tried and do not want to try it anymore. You can also go this way, but to achieve "not very bad" performance it'll take much more than a day and much more than few $$, even if you have unlimited access to older ACs.
OK, i think that's enough for this appendix, this is a controller page, and not how-to-build-refrigeration-systems page.
## Appendix D: Firmware options and fine tunings