How To Service and Maintain An EZ Tankless Water Heater
Tankless water heaters have to be cared for as with any household appliance. Tankless water heaters can be flushed and cleaned in little time.
How To Remove and Clean Intake Screens
All EZ Tankless water heaters have a screen inside the water inlet side of the heater. (similar to those used on intake water lines of washing machines) This screen is the last line of defense to keep particles from entering the water flow sensor housing and inhibiting the use of the heater. This screen should be inspected and cleaned periodically for maximum efficiency.
The vast majority of screen blockages are caused by plumber's putty "pipe dope" or plastic "Teflon©" sealing tape. In the images below you can see examples of blockages.
In the first image, chips of white paint and rubber cement were found to be blocking the intake screen. These pieces are also shown in the image on the bottom left. Who knows how this material enters a plumbing system.
The top row middle image is well-water debris from only ten days use. Under magnification we discovered that this sludge included insect carcasses and unknown gunk. Just imagine, this user from Michigan is drinking this well water!
The top right image is a paper obstruction of the inlet water flow sensor turbine. After the intake screen became clogged, this user decided to remove it and promptly clogged the interior components of the heater. How paper gets into a water system is a mystery but it could be from a small product information sheet that someone inadvertently rolled-up and placed into a pipe section.
In the bottom right image we can see that plumber's tape was accidentally wrapped across the opening of the gas line inlet. This caused a malfunction due to an inadequate supply of natural gas.
Drain/Flush Operation For A Tankless Water Heater
WARNING: Very hot water may be present in the system during this process. The risk is especially high if the heater has just been running prior to the cleaning operation. Always use extreme caution when servicing a tankless water heater. Hot water can cause personal injury, death and/or property damage.
Note: Vinegar is the typical agent used to clean a tankless heater. The reason that you must use a cleaner of this type is simple. This is a potable (drinking water) system and harmful chemicals must never be used in the cleaning operation.
WARNING: NEVER USE CHEMICALS for cleaning a tankless heater. THIS IS A DRINKING WATER SYSTEM! Even minute amounts of chemicals can remain in a plumbing system even after thoroughly flushing and rinsing, and are possibly harmful or fatal if ingested by humans or animals.
These are suggested instructions for the use of service valves for the purpose of draining and flushing a tankless water heater. You may wish to also refer to the product owner's manual for more specific instructions.
- Disconnect the electrical power supply to the water heater. Close the main water valve handles on the cold water valve (blue handle) and the hot water valve (red handle) by rotating each until they are perpendicular with the respective valve body. This shuts off the incoming cold water to the water heater and isolates the water heater from the hot water pipes going into the plumbing system of the home or business.
- On the cold water valve (blue), there is a purge valve with a small T-Handle. This is used as the flushing inlet and the opposite purge valve on the hot water side (red) is used for the flushing outlet or return drain. Be certain that the outlet hot water purge port (red) is closed (perpendicular to the purge port valve body) before removing the purge port valve cap.
- Slowly open the drain caps on each purge port valve. Always be sure to inspect the cap to ensure that the rubber washer sealing disc stays in each respective cap.
- Continue with the manufacturer's recommended procedure for attach¬ment of the lines and for specific draining and flushing instruc¬tions. To open the purge port valves, the T-Handles on the port outlet pipes are rotated so that they are parallel to each purge port valve body.
- When flushing is complete and before the lines are removed, verify that the purge port valves are closed. Remove the lines and reinstall the purge port valve caps, ensuring that the rub¬ber washer is in the cap, and tighten. (NOTE: To prevent damage to the rubber sealing discs (washers), do not over tighten these caps.)
- Re-start-up & return to normal operation
- Before turning on the supply water to the heater, make sure that the main valve handles on both the hot & cold valves are closed (perpendicular to the main valve bodies). Also ensure that the purge port valve caps are tightened down and that the valves are in the closed position (T-Handle perpendicular to the purge port valve body). WARNING: NEVER RELY ON THE PURGE CAP TO STOP THE WATER FLOW
- For water heater start-up, refer to the water heater owners' manual.
- During normal operation, the main water valves are open when the main valve handle is parallel with the main valve body and closed when the main valve handle is perpendicular to the main valve body. To return the heater to operation, rotate the main water flow handles to a parallel position in alignment with the main valve body. At this time, water will begin entering the heater. Slowly open a hot water tap in the sink and allow the air to pass through the system until the water no longer is burping air. With the hot water tap opened and running, wait for several seconds to be sure that the lines are cleared of air. At this point, you should run the hot water tap for a minute or two to clear any residual air and cleaning agent from the system
Reminder: For the purge port valves, the purge port valve is open when the T-Handle is parallel with the purge port valve body and closed when the T-Handle is perpendicular to the purge port valve pipe.
Typical Materials Needed to Flush a Tankless Water Heater
1 utility pump (Typically, this type of utility pump is self-priming.)
3 hoses (Typically the utility pump comes with 1 hose. Additionally, washing machine hoses work well for this operation.)
2 buckets (one or five gallon)
2 gallons (+/-) white vinegar
SET-UP: Attach one hose from the hot outlet service port of the tankless water heater to one of the buckets. Attach one hose from the inlet of the pump to another bucket. Attach one hose from the pump to the cold water inlet service port of the tankless water heater.
HOW IT WORKS: The flow from the first bucket filled with fresh vinegar goes into the pump. The pump sends the vinegar into the water heater via the cold water service port and then out the hot water outlet port into the second bucket.
PROCEEDURE: Simply open the service port valves and turn on the pump. The vinegar will begin to flow through the tankless heater and come out of the hot side outlet service port into the return waste bucket.
WHAT PERIOD OF TIME IS NECESSARY: Due to many variables, the time that this cleaning procedure will take is not something that can be predicted. Depending upon the preparedness and abilities of the person doing the work, the hardness of the water, if there is a softener in use, and how long it has been since the last cleaning, it may take as little as 45 minutes or as long as a couple of hours. Repeat this procedure as many times as necessary until the vinegar runs clean into the return bucket.
During this operation, you may chose to let some vinegar sit in the heater for a few minutes. Do this by isolating the vinegar by turning off the port valves. First close the outlet hot side port service valve, followed by the cold side port service valve. Then immediately turn off the pump. Then, in a few minutes re-open the service valves, re-start the pump and see if this may have loosened any additional scale.
Finally, do the same procedure with fresh water to flush all remaining vinegar from the tankless heater. Do this until you have run about five buckets of clean water through the heater.
DISPOSAL OF REMAINING SOLUTION: Vinegar is not harmful and even the most environmentally conscious person can simply pour this solution down the household drain.