What should be the procedure for winterizing the Noritz NC199 DVC if it's installed in a seasonal residence?

Winterizing your Noritz NC199 DVC tankless water heater when it's installed in a seasonal residence is essential to prevent freezing and potential damage to the unit during the cold months when the property is not in use. Here's a step-by-step procedure for winterizing your tankless water heater:

Materials and Tools You'll Need:
* A bucket or container
* A submersible pump (if not already installed)
* A non-toxic RV or marine antifreeze (ethylene glycol-based)
* Garden hose and fittings
* Pipe insulation or heat tape (optional)
* Basic plumbing tools (wrench, pliers)
* Teflon tape (thread seal tape)
Procedure:
* Shut Off the Power and Gas:
* Turn off the power supply to the Noritz NC199 DVC by switching off the circuit breaker or disconnecting the electrical power source.
* Locate the gas supply valve or gas isolation valve for the water heater and turn it off to shut off the gas supply.
Drain the Water Heater:
* Connect a hose to the drain valve of the water heater. Ensure that the hose is long enough to reach a suitable drainage area or drain point outside the seasonal residence.
* Open a hot water faucet inside the residence to allow air into the system.
* Open the drain valve on the water heater to start draining the water from the unit. This will remove water from the heat exchanger and plumbing lines.
* Allow the water to drain completely from the water heater. You may need to wait a few minutes for all the water to drain out.
* Once the water heater is empty, close the drain valve.
Bypass the Water Heater:
* Install a bypass kit or use manual valves to create a bypass around the water heater. This step prevents antifreeze from entering the water heater itself. If your Noritz NC199 DVC has built-in isolation valves, use them to isolate the unit.
Prepare the Antifreeze Solution:
* Mix a non-toxic RV or marine antifreeze with water according to the manufacturer's instructions. Typically, you'll dilute the antifreeze with water in a 50/50 ratio.
* Pour the antifreeze solution into a clean bucket or container.
Use a Submersible Pump (if necessary):
* If your Noritz NC199 DVC does not have a built-in recirculation pump, you'll need to use a submersible pump to circulate the antifreeze throughout the plumbing system.
* Place the submersible pump in the antifreeze solution and connect it to the water heater's inlet or hot water outlet.
Circulate Antifreeze Through the Plumbing:
* Turn on the submersible pump (if used) to start circulating the antifreeze through the plumbing system.
* Open each hot water faucet, one at a time, until you see the antifreeze coming out. This ensures that the antifreeze reaches all plumbing lines and fixtures.
* Continue this process for all hot water faucets and fixtures, including showers, sinks, and any outdoor faucets.
Check Toilets and Dishwasher:
* Flush each toilet to ensure that antifreeze is present in the toilet tank.
* Run the dishwasher through a short cycle to ensure that antifreeze circulates through its water lines.
Insulate Exposed Plumbing:
If your seasonal residence is prone to extremely low temperatures, consider insulating any exposed plumbing lines or using heat tape to provide additional protection against freezing.
Close and Seal Fixtures:
* Close all hot water faucets and fixtures.
* Seal the drain openings of sinks, tubs, and showers with appropriate drain plugs or stoppers to prevent antifreeze from evaporating.
Shut Off the Submersible Pump:
If you used a submersible pump, turn it off once the antifreeze has circulated through the plumbing system.
Power Off and Gas Supply Closed:
Ensure that the power supply to the water heater remains off, and the gas supply valve to the unit is closed.
Periodic Maintenance Checks:
If your seasonal residence remains unoccupied for an extended period, periodically check the plumbing system and antifreeze levels to ensure everything remains in good condition.

By following this winterization procedure, you can protect your Noritz NC199 DVC tankless water heater and plumbing system from freezing temperatures during the winter months when your seasonal residence is not in use. This preventative maintenance will help ensure that your tankless water heater operates smoothly and efficiently when you return to your property in the spring.