John Wood Power Direct Vent (Non-ENERGY STAR qualified models) - Manual (Page 28)

VI) MAINTENANCE
Draining and Flushing
It is recommended that the tank be drained and flushed
every 6 months to remove sediment that may build up dur-
ing operation. The water heater should be drained if being
shut down during freezing temperatures. To drain the tank,
perform the following steps:
1. Turn off the gas to the water heater at the manual gas
shut-off valve.
2. Turn off the electrical supply to the water heater.
3. Close the cold water inlet valve.
4. Open a nearby hot water faucet.
5. Connect a hose to the drain valve and terminate it to an
adequate drain.
Note: The drain hose should be rated for at least 93°C
(200°F). If the drain hose does not have this rating, open the
cold water inlet valve and a nearby hot faucet until the water
is no longer hot.
6. Open the water heater drain valve and allow all the
water to drain from the tank. Flush the tank with water
as needed to remove sediment.
7. Close the drain valve, refill the tank, and restart the
heater as directed under “Water Heater Operation”.
If the water heater is going to be shut down for an extended
period, the drain valve should be left open.
Important: Condensation may occur when refilling the tank
and should not be confused with a tank leak.
Routine Preventative Maintenance
At least annually, a visual inspection should be made of the
venting and air supply system, piping systems and main
burner. Check the water heater for the following:
•
Obstructions, damage or deterioration in the venting
system. Make sure the ventilation and combustion air
supplies are not obstructed.
• Build up of soot and carbon on the main burner. Check
for a soft blue flame.
• Leaking or damaged water and gas piping.
• Presence of flammable or corrosive materials in the
installation area.
• Presence of combustible materials near the water
heater.
• Verify proper operation after servicing this water heater.
Important: If you lack the necessary skills required to prop-
erly perform this visual inspection, you should not proceed,
but get help from a qualified service technician.
Temperature and Pressure Relief Valve
Manually operate the temperature and pressure relief valve
at least once a year to make sure it is working properly (see
Figure 21). To prevent water damage, the valve must be
properly connected to a discharge line that terminates at an
adequate drain. Standing clear of the outlet (discharged
water may be hot), slowly lift and release the lever handle
on the temperature and pressure relief valve to allow the
valve to operate freely and return to its closed position. If the
valve fails to completely reset and continues to release
water, immediately shut off the manual gas valve and the
cold water inlet valve and call a qualified service technician.
Replacement Parts
Replacement parts may be ordered through your plumber or
the local distributor. When ordering replacement parts,
always have the following information ready:
1. model, serial and product number
2. type of gas
3. item number
4. parts description
See “Replacement Parts Illustration” for a list of available
repair parts.
– 28 –
Temperature and Pressure
Relief Valve
Manual Relief Valve
Discharge line to drain
Figure 21 T&P Valve Test
WARNING
Explosion Hazard
• If the temperature and pressure relief
valve is dripping or leaking, have a
licensed plumber repair it.
• Do not plug valve.
• Do not remove valve.
• Failure to follow these instructions can
result in death or an explosion.