Winterizing tankless WH

[RStarkey]

I have a 2022 Alpine 3712KB and when winterizing we switched the WH bypass and proceeded to do the antifreeze thing. No problem done this many times with other campers. Further thoughts on this process I come to realize we have a tankless WH. In reading the procedure for winterizing either blow it out or run antifreeze through it. So why is there a WH bypass on it? So now I will have to get some more juice and turn the bypass off and do the hot water lines again.
Am I wrong on my plans?
Thanks Rick

[Mikendebbie]

Following this thread with interest.
I have Suburban IW60 tankless. I have used air to blow out my RV for winterizing. Never have used the pink stuff. I know the IW60 manual has instructions for winterizing but I have never done it that way. I’m in TX - so winters are usually not harsh - with 2 exceptions of course…Feb 2021 and Dec 2022 we had a week of temps in the 10s and no power due to ice storms.
Knock on wood - the air blow winterizing has worked for me.

Your Alpine may have the recirculating version of the tankless water heater. I have no idea what extra measures you may need to take.

[Gamma]

Watching thread as I live in New England. I have an Alpine with the Suburban tankless and the recirculating loop. The manual (both Keystones and Suburbans) are a bit vague when it comes to this. It looks like you remove the wall panel inside the storage compartment to access a drain valve on the back of the heater box.

[jxnbbl]

I've started looking for a new 5th wheel and each of the options have tankless water heaters...so I've been thinking about this same question as I winterized our trailer just this week. For tankless I would probably NOT use the bypass (assuming it has the same meaning as the std water heater) and then run one of the bathroom sinks or shower with the two separate faucet handles..running hot water only until I see pink liquid flowing.

[ChuckS]

If you folks with the IW60 or IW60RL ( Alpines came STOCK with IW60RL ) from factory dont winterize properly you will be sorry come next season.

There is one way and one way ONLY to winterize that Airxcel on demand WH...

Access the WH and open the drain and blow it out with air or use RV antifreeze and do it that way...

If you dont you will crack one or more items:
.. recirculation pump on the RL model
.. WH tank within the unit itself
.. Heat exchanger chamber

in 2023 Alpines started coming with Girard GSHW-2 and it has its own set of water leak issues as well

** This recall was back on the 2019-2020 units when several were not winterized from factory correctly and it resulted in cracked tanks

Read the WINTERIZE procedure as outlined in this link:
https://static.nhtsa.gov/odi/tsbs/20...70646-0001.pdf

[jxnbbl]

Chuck,

So in summary reading that:

1. Purge the HW system of water.
2. connect the antifreeze container to the winterization port.
3. turn on the onboard pump.
4. run HW faucet until pink

On #1, I'm guessing this is opening the mentioned drain on the bottom of the unit or possible blowing air through HW system first before proceeding to #2?

[ChuckS]

Originally Posted by jxnbbl

Chuck,

So in summary reading that:

1. Purge the HW system of water.
2. connect the antifreeze container to the winterization port.
3. turn on the onboard pump.
4. run HW faucet until pink

On #1, I'm guessing this is opening the mentioned drain on the bottom of the unit or possible blowing air through HW system first before proceeding to #2?

Yup that is the way to winterize this WH correctly to prevent cracks in the internals

[ChuckS]

A couple of images of what WILL crack on the IW60 and IW60RL water heaters if not winterized correctly

Either the recirculating pump on the RL models and/or the WH tank itself ..

[Gamma]

Yessir, I was sure we needed to do something with that drain valve. Thank you for your help on this as I would like to not deal with something that can be easily prevented.

Thanks again.

[RStarkey]

Ok so far the rlpump has broken. New one coming. Back to the draining. I find one with a knob on the outside, quarter turn and that will drain the tank. Inside is another valve that looks like to drain the coil. Also another valve of sorts??? On the bottom outside edge, flat blade brass screw. Not sure what it's for. What a pain in the rear end. Not very user friendly. Did miss anything for draining purposes??
Thanks Rick