How to Winterize my Airstream Interstate?

[Interstate1]

Hello, I am a newbie at this whole thing...Could someone please explain to me the steps on what I need to do to winterize my Interstate? I live in Michigan so the winters can be pretty brutal. Thank you.

[Interstate1]

Oops! I posted this in the wrong spot... Sorry

[Protagonist]

Originally Posted by Interstate1

Oops! I posted this in the wrong spot... Sorry

Ask a mod to move this thread to the Sprinter and B-vans Forum. They can do that. But since you shouldn't have to wait for an answer…

The basics of winterizing should be covered in Section G of your Airstream Interstate Owner's Manual, under the heading "Storage and Winterizing."



A few things the manual doesn't address…

• In step 5, do not remove the shower hose like it says, You'll see why momentarily.
• In step 6, "apply at least 60psi of air pressure at the city water inlet" you'll need a blowout plug for that. I use a Camco 36153 brass blowout plug. But you should reclose the low-point drains and leave both faucets open halfway between hot and cold so that you can blow out the whole system, and not just the part of the system between the city inlet and the low point drains.
• When you're blowing out the lines, do it with the exterior shower connected as well. You don't need to blow out the hose, but you can't blow out the fitting on the side of your Interstate without the hose connected.
• After everything is blown out, reopen your low point drains.
• The manual does not address using RV antifreeze in your plumbing; they assume you'll blow everything dry. Dry pipes won't freeze.
• But you also have to winterize your wastewater systems. You do this by pouring some RV antifreeze into your toilet, down both sinks and your shower drain, and opening your black and gray valves to get antifreeze into the hoses between the tank and the macerator pump.
• Pull out all of your discharge hose and lay it flat on the ground, with the valve on the end of the hose open. Then pump out a little bit of your antifreeze. The puts antifreeze into your macerator pump, and helps to make sure you don't have any water trapped in your discharge hose. Don't pump out ALL the antifreeze, just enough to clear any water from the pump and hose.
• After you shut off the macerator pump, you can coil the discharge hose back up. At that point you should be pretty much done.
• If you don't have shore power, remove the batteries and store them inside. They shouldn't freeze, but doing that will also let you trickle-charge them on a bench from time to time to keep them charged.
• Since we're talking about Michigan, either fill the diesel tank with #1 (winter blend) diesel, or get a good additive that will prevent the fuel from gelling.

I'm sure others will chime in with stuff I've forgotten. Living on the Gulf Coast, I don't have to be quite as scrupulous about winterizing. Last winter I didn't winterize at all, and got away with it. But I try to keep up with procedures because I'm not always so lucky.

[Kevin245]

Originally Posted by Protagonist

Ask a mod to move this thread to the Sprinter and B-vans Forum. They can do that. But since you shouldn't have to wait for an answer...

Got you covered.

[polarlyse]

Just to add re: batteries. If you chose to remove and store at home you can get what's called a battery tender. Most trickle chargers will still charge too much for a constant hook up. The tenders are designed for this and will maintain a charge at a low enough level that you can leave it on long term while in storage. I choose to blow the lines on our trailer. Has worked nicely for our NJ winters but you will need a compressor for this. I do put RV antifreeze into the traps under the sinks, shower and into the toilet. Remove any filter cartridges and replace with new in the spring and don't forget to drain your hot water tank. I disconnect the lines into and out of the water pump and also disconnect the shower hose after blowing the lines. If you choose to fill the system with RV antifreeze there is lots of help here on the forum from those that go that route b ut determine if your water heater has a bypass installed. If not you will be filling the tank with the antifreeze.
It seems to work well but you will need to flush your lines well in the spring. It's not difficult and if you do it yourself it assures that you are stay friendly with your plumbing system.

PS: If you have the black tank spray system I think you also should hook your compressor and blow the lines there also.

Good luck with your winterizing.

[Interstate1]

I greatly appreciate all your feedback... Thank you soooooo much :-)

[K9CarCrate]

I have a 2014 Interstate ext with the solar panel option. Do I still need to remove the batteries? I was told by my dealership that the solar panels will in effect keep the batteries charged, but have not been able to find anything in the manual to support this. Thanks.

[Protagonist]

Originally Posted by K9CarCrate

I have a 2014 Interstate ext with the solar panel option. Do I still need to remove the batteries? I was told by my dealership that the solar panels will in effect keep the batteries charged, but have not been able to find anything in the manual to support this. Thanks.

Whether you need to remove the batteries is more a function of climate. In your case, in Virginia, it probably doesn't get cold enough to require removal of the batteries.

But for general reference, if it gets cold enough to remove the batteries, that means ALL of the batteries, house batteries in the rear, chassis battery under the driver's foot well, auxiliary battery under the hood if yours has one. The solar panel will only keep the house batteries charged; it's not connected to any others.

[gmillerok1]

I use a different approach. I use antifreeze on all the lines.

First, I drain the hot water tank by removing the drain plug, and turn the diverter valve to close the hot water tank to keep the antifreeze out (as stated in the manual).

I then put two gallons of RV antifreeze (never any other kind as it is poisonous) in the fresh water tank. Then, turning on and using the water pump, I open the hot/cold faucets in the kitchen, bath and shower and toilet until pink antifreeze comes out. I either remove or run it through the hand shower as well. I place the black tank flush hose on the connection to the flush line and plug it into the outside shower connection, and put antifreeze in the black tank flush line (and valve) to keep it and the shower connection from freezing (learned the hard way the backflush valve in the flush line WILL freeze and the pex plumbing potentially can as well).

This makes sure all the connections, including the water pump, are protected, and no water could freeze anywhere.

I then put another gallon of antifreeze in the black and grey tanks by pouring it down the toilet and sinks (to protect the traps). I then run the antifreeze through the dump hose using the macerator until pink fluid comes out the hose to protect the hoses, valves and macerator. After that, I'm done.

To take it out of the mode, I simply drain the water tank and put fresh water in, and also run water using the inlet hose connection through all the same connections until it runs clear except for the flush line and dump lines, which doesn't really matter if they contain antifreeze or not. Next dump it all will come out anyway.


Gerald

Originally Posted by Interstate1

Hello, I am a newbie at this whole thing...Could someone please explain to me the steps on what I need to do to winterize my Interstate? I live in Michigan so the winters can be pretty brutal. Thank you.

[MILATV]

Originally Posted by gmillerok1

I use a different approach. I use antifreeze on all the lines.

First, I drain the hot water tank by removing the drain plug, and turn the diverter valve to close the hot water tank to keep the antifreeze out (as stated in the manual).

I then put two gallons of RV antifreeze (never any other kind as it is poisonous) in the fresh water tank. Then, turning on and using the water pump, I open the hot/cold faucets in the kitchen, bath and shower and toilet until pink antifreeze comes out. I either remove or run it through the hand shower as well. I place the black tank flush hose on the connection to the flush line and plug it into the outside shower connection, and put antifreeze in the black tank flush line (and valve) to keep it and the shower connection from freezing (learned the hard way the backflush valve in the flush line WILL freeze and the pex plumbing potentially can as well).

This makes sure all the connections, including the water pump, are protected, and no water could freeze anywhere.

I then put another gallon of antifreeze in the black and grey tanks by pouring it down the toilet and sinks (to protect the traps). I then run the antifreeze through the dump hose using the macerator until pink fluid comes out the hose to protect the hoses, valves and macerator. After that, I'm done.

To take it out of the mode, I simply drain the water tank and put fresh water in, and also run water using the inlet hose connection through all the same connections until it runs clear except for the flush line and dump lines, which doesn't really matter if they contain antifreeze or not. Next dump it all will come out anyway.


Gerald

EXACTLY WHAT I DID Gerald! all lines protected; good to go. Only thing I do that wasn't on your list was to use my rinse wand to rinse out the hot water tank (remove any sediment) but guess you could do that in the spring. Full System Flush and Prep was 4 gallons for me; and that left fresh water tank pretty much dry. (water pump started spurting just as I shut it off)

[Tiato]

Originally Posted by gmillerok1

I use a different approach. I use antifreeze on all the lines.

First, I drain the hot water tank by removing the drain plug, and turn the diverter valve to close the hot water tank to keep the antifreeze out (as stated in the manual).

I then put two gallons of RV antifreeze (never any other kind as it is poisonous) in the fresh water tank. Then, turning on and using the water pump, I open the hot/cold faucets in the kitchen, bath and shower and toilet until pink antifreeze comes out. I either remove or run it through the hand shower as well. I place the black tank flush hose on the connection to the flush line and plug it into the outside shower connection, and put antifreeze in the black tank flush line (and valve) to keep it and the shower connection from freezing (learned the hard way the backflush valve in the flush line WILL freeze and the pex plumbing potentially can as well).

This makes sure all the connections, including the water pump, are protected, and no water could freeze anywhere.

I then put another gallon of antifreeze in the black and grey tanks by pouring it down the toilet and sinks (to protect the traps). I then run the antifreeze through the dump hose using the macerator until pink fluid comes out the hose to protect the hoses, valves and macerator. After that, I'm done.

To take it out of the mode, I simply drain the water tank and put fresh water in, and also run water using the inlet hose connection through all the same connections until it runs clear except for the flush line and dump lines, which doesn't really matter if they contain antifreeze or not. Next dump it all will come out anyway.

Gerald

Did it that exact same way 2 weeks ago when I went to central Vermont to visit my son at school.

[Boxster1971]

The link below is to a 16 minute video on winterizing a Roadtrek B-van. Although it isn't specific to an Airstream Interstate it does have some great tips by a professional technician from American RV is Michigan. Things like:

• drain all holding tanks before winterizing
• using air to expel residual water in water heater before by-passing it
• don't but any antifreeze in fresh water tank
• use adapter to pump anti freeze into interior lines directly
• add antifreeze to drain traps and leave faucets open
• add several inches of antifreeze to toilet bowl
• drain tanks again after winterizing
• add antifreeze to holding tanks and pump it though macerator
• use antifreeze to flush toilet for winter use

How to winterize your Roadtrek Class B RV: VIDEO | The small motorhome lifestyle

Enjoy!

[jerhofer]

Since we will be making a trip to northern Indiana at Thanksgiving, I decided I should winterize our 2013 AI while the weather was still nice here. I printed off "Protagonist's" list and, combined with the owner's manual, did the deed today. While there are many great suggestions here, there are no photos. There will be some now.

Since my driveway is sloped, the first thing I did was level the home with my recently purchased leveling blocks.



After running the fresh water into the commode and gray water tank, I crawled under the coach to find the tank drain. Since I had not looked under here before, I also snapped a photo of the LP gas tank. The drain plug takes a 1" socket.









Next I found the water heater drain plug which needed a 15/16" wrench. I noticed a bit of water beneath the plug and determined that the plastic plug had been crossthreaded. After completing the winterizing, I found a brass plug at the local hardware store. It uses an Allen wrench socket and is now much easier to install and remove.











It was mentioned to open the WH pop off valve. The first photo shows it in the closed position while the second one is the open position.





There are two sets of low point drains in our home. One is under the passenger side cup holder at the rear of the home.





The other pair require removing the drawer under the sink cabinet. Pull the drawer as far out as it will go and a black tab is revealed on each side. Depress these tabs to remove the drawer. The water pump is also located here.







I bought two brass blow out fittings. One is to be used with a tire inflator fitting and the other one is a male fitting to directly attach the hose to. I used the tire fitting on the black tank flush connector but found the male hose fitting worked best when blowing out the water lines as I could leave it attached and monitor the progress inside the house. I set my compressor gauge at 60psi.











The only other photo of interest was showing the location of the WH bypass valve which is on the rear of the WH under the seat.





I am glad I did this myself as I now know my way around the home much better than before. Next time will go much faster.

[Boxster1971]

Nice job on including all those photos. Thanks for taking the time to post this information.

- - Mike
2013 Lounge EXT on 2012 Sprinter

[scarletbison]

jerhofer,

in the 2nd to last photo, there are two loosened screws on the front of the casework. Is that how you open the casework to get at the water heater?

[jerhofer]

Originally Posted by scarletbison

jerhofer,

in the 2nd to last photo, there are two loosened screws on the front of the casework. Is that how you open the casework to get at the water heater?

I did loosen those screws but it would not have been necessary as the panel could not move very much without removing other components. You can still reach the valve with the panel attached. Barely!

[73shark]

Don't you still need to get some RV antifreeze in the grey and black water tanks in order to winterize the valves, macerator pump, and hose?

Great job on the pics and description. Hadn't thought about the relief valve altho not sure what that will do as far as draining the HW tank.

[jerhofer]

Originally Posted by 73shark

Don't you still need to get some RV antifreeze in the grey and black water tanks in order to winterize the valves, macerator pump, and hose?

Great job on the pics and description. Hadn't thought about the relief valve altho not sure what that will do as far as draining the HW tank.

Since Protagonist did such a great job with his list, I didn't cover everything that I did which included using rv antifreeze. I followed his list but provided photos of items I thought would be of interest and would supplement his list.

Opening the relief valve noticeably increased the water flow.

[Interstate1]

Awesome job! We should put together a small video showing the steps too. We can post it on youtube for easy access for all Airstream Interstate owners...that will be my goal for next year if nobody gets to it first.


Sent from my iPhone using Airstream Forums

[Dungrace]

Jerhofer,

Did you add that aluminum cover on top of the water heater drain plug? I didn't see one on my 2014.5.