The Ultimate Outdoor Wood Boiler Summer Shutdown Checklist!

The Ultimate Outdoor Wood Boiler Summer Shutdown Checklist!

This is our New And Improved Ultimate Summer Shutdown Checklist!

Complete this checklist even if you plan to keep your outdoor wood boiler running all Summer. Please keep in mind that if you use your outdoor wood stove in the summer, you'll need to take extra precautions to protect your boiler.

1.) First, watch this video below for a quick refresher of the

The Ultimate Summer Shutdown Video

 "Summer Shutdown " process. 

2.) Make sure to follow all safety precautions!

Our customers are very smart and cautious when it comes to safety. Just please remember to be careful!

3.) Put in TWO Creosote Remover Sticks in the firebox THREE DAYS before shutting down your furnace.

Creosote Remover Sticks are SUPER EASY because they require no measuring and will simply dry up harmful creosote in your outdoor wood burner. Click HERE for instructions, more info, and to order online.

4.) Allow the fire to completely burn down. 

You may wish to preserve your dry coals for Fall Startup. Many people do this since starting your furnace in the fall with a load of dry coals (rather than ordinary firewood) will result in significantly less condensation, moisture, and creosote as it heats up.

 When the water jacket temperature falls below 140 degrees, intense condensation and creosote occur. Also, even well-seasoned wood contains at least 20% moisture, which causes starting a cold furnace, especially a GX type, more difficult.

 Any moisture from the firewood will condense on the inside burn pot and tube walls when starting a cold boiler with a water jacket temperature below 140 degrees. We occasionally receive calls from clients who believe they have a leak!

5.) Remove all the ashes and lightly scrape the firebox.

Be sure that all ashes are removed. Dry ashes are harmless, but if left in your outdoor boiler over the summer, these dry ashes will absorb moisture and create a caustic paste that will eat through your steel firebox.

We strongly urge you to use a shop vac to vacuum the remaining ash to be sure your burn pot is completely clean and no ash remains during the humid Summer months. Moist ash is dangerous and must be avoided.

6.) Clean the water filter. 

Remove the filter cartridge and clean it completely. If the cartridge is more than 4-5 years old, it must be replaced, even if it looks ok. Do not clean with the quick flush method but rather clean the cartridge completely. 

Do NOT over-tighten the filter housing. If you have not replaced your filter O-Rings in the last 2-3 years, replace them now. Click HERE to read "Why Is My Filter Leaking?" Order new filter O-rings HERE.

If you do not have a water filter, click here to read the article "Why Do All Outdoor Wood Boilers Require Filters?"

7.) Do A Sediment Flush

You must do one of the following flush procedures - you must EITHER:

A) Annual Sediment Flush - You simply open the rear drain valve for 5 seconds to do a quick sediment flush. OR,

B) Complete Water Flush - This procedure completely replaces the water in your outdoor boiler.

Which of the two is required for your system?

Here is how to determine which one: The Annual Sediment Flush must be done every year. Many people don't realize this, but it is a critical annual maintenance item. 

This must be done before you take your water sample from the rear drain. (Please, never take your water sample from the filter.) Take 30 seconds to read more about this simple procedure in this article "How To Protect Your Boiler From Sediment Damage".

 Is it time for your boiler to get a COMPLETE WATER FLUSH? You must immediately FLUSH your boiler water if you have not done so in the last four years. Other circumstances also require a complete flush, such as using unauthorized treatment chemicals in your boiler.

8.) Your boiler must always be completely full of properly treated water. NEVER allow your boiler to remain empty - rust will form immediately unless it is completely full of properly treated water. You'll need to add the appropriate amount of Liquid Armor water treatment.

You have made a big investment in your outdoor boiler, and if you don't properly treat your furnace water, it is similar to driving a car without oil. It will only be a matter of time before your furnace will be destroyed from corrosion.  

9.) Send a water sample to the Lab for your FREE water test. 

10.) Make sure to REMOVE the chimney cap and clean out the chimney area! 

This is very important and often overlooked - remove the chimney cap, clean the inside of the chimney with a wire brush, then vacuum out the entire area with a shop vac. You will find it hard to remove the chimney cap if you fail to complete this important step every year.

 Use the D-Plate Brush to clean the deflector plate as well. From above, push the wooden handle down the chimney and towards the front until it stops. Then open the front door, reach up and grab the handle and pull the D-Plate brush through.

Repeat this process numerous times. To order, see HERE(GX Model furnace owners do this cleaning with the GX10 Cleaning Brushes available here while GX15 and GX30 HERE)

 Then, from the front of the furnace, pull the pull rod to its stop, then turn it clockwise until you can pull it past the stop. Pull it towards you all the way until it scrapes off the entire deflector plate. For more info on Pull Rod Best Practices, click HERE(Not necessary for GX Model owners.)

 Never leave your outdoor boiler without a chimney cap. So be SURE to replace the chimney cap for the Summer rainy days. Alternatively, you can secure a bucket over the chimney to keep the rain out.

11.) Replace Door Seal 

Has your door seal been replaced in the last 2-4 years? If not, replace the door seal as needed. Click HERE to read our article "6 Ways a Leaky Door Seal COSTS You Money".

12.) Turn the power off at the breaker/power source

Turn off the power to the outdoor furnace at the breaker. Or to protect and prolong the life of your pump, leave the power on and allow the pump to circulate. Your choice.

If you do this, turn off the blower fan and unscrew the light bulb. Click HERE to read our article "Should I Keep My Pump ON All Summer?" 

Also, turn off power to your thermostats that control outdoor wood furnace operation - your indoor forced air extra thermostat, any unit heater thermostats, in-floor systems, etc.

Bonus: You should also check to make sure your pump is set at the proper speed. Take 60 seconds and become an expert with this article: "What Speed Should Your Pump Be Set At?"

13.) Check the Owner's Manual for full details. 


By carefully following this New and Improved 2022 Ultimate Summer Shutdown Checklist, you are protecting and caring for your outdoor wood burning boiler so it will take care of you for decades and help you save thousands of dollars each year on your heating bills!

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