Below are the steps I take to winterize after each trip. I perform these steps at the campsite before leaving.
I have gone through this routine about a half dozen times this season with only one failure – in one instance I forgot to purge and add anti-freeze to the toilet causing a small and inexpensive plastic valve at the back to break. Don’t forget the toilet!
I have this down to about a 20 – 30 minute process.
My instructions are below. For items that may benefit from a bit of visualization, photographs are inline.
1. Turn off hot water heater (switch probably in the bathroom).
2. Run hot water until cold.
3. Disconnect city water line.
4. Remove water filter (under the galley sink).
5. Open low point drains.
6. When low point drains stop flowing, close again.
7. Open faucet and turn to hot (nothing will flow). This prevents the hot water tank from “gulping” as you drain it.
8. Open hot water tank from the outside – stand to the side! Leave this open while being transported and stored.
The 3/4″ drain plug can be difficult to wrangle due to its extraordinarily bizarre placement. I use pliars.
9. Once hot water tank is drained, close bypass valve and close faucet previously opened (step 7). This valve is located by the hot water tank which, in the 28′ International, is under the front couch next to the sink.
Note the winterized and non-winterized position – it will be marked next to the valve.
10. Hook up air compressor – set to 50 PSI.
In the photograph above you will see my Bostitch pancake compressor attached to my water hose using a Camco Blow Out Plug. This purges the hose as well allowing it to be stored safely in the Airstream.
11. Go back inside, open up all faucets (including toilet and shower) one by one and purge. Repeat as necessary. You’ll probably be surprised how much water comes out.
11(a). You may need to do this for the outside shower as well unless you have previously winterized this.
11(b). You should purge the black tank flush intake as well. Do this once at the beginning of winter and don’t bother flushing the black tank for the remainder of winter.
12. De-pressurize compressor & detach from Airstream.
13. Open faucets and de-pressurize the system.
14. Attach anti-freeze hose line to anti-freeze.
In the photograph above you can see a cheap Camco 36543 winterizing kit installed. This is a one minute install. Just leave it in place forever once installed.
15. Turn on pump. Run faucets (including toilet and shower) one by one until pink comes out. Do not forget the toilet!
15(a). Do this for the outside shower as well. We avoid using the outside shower in winter after it has been winterized.
16. Put a cup of anti-freeze down all sinks, showers and into toilet bowl.This prevents (in theory) the rubber toilet bowl seal from drying out and cracking.
17. Re-open low drains and leave open while being transported and stored.
18. Drain fresh water tank (pepcock between wheels on road side) and leave pepcock open while being transported and stored.
19. Dump black and grey tanks.
You may have to shovel out the dump station.
A nice video on this topic here, showing location of the low point drains and fresh water tank drain pepcock.
2015-02-18 update – things you’ll need:
- Air compressor
- Camco 36143 Blow Out Plug with Brass Quick Connect
- Camco 36543 winterizing kit
- RV anti-freeze
– Anthony, Waukee, Iowa