QuickDraw
Storage and Semi-instantaneous
Boiler Water Heater
13
PV500-26 05/13
7 MAINTENANCE
WARNING: Turn off all electrical service to the appliance when accessing the remote connections located
inside the control cabinet. These terminals are high voltage. If the electrical service is not turned off and
these terminals are touched, a dangerous shock causing personal injury or loss of life could occur. Close
and fasten the control cabinet cover before restoring electrical service to the appliance.
7.1 Temperature and Pressure Relief Valve
Operate the temperature and pressure relief valve at least once a year by lifting the lever briefly. If the valve does not
open and close properly when testing, it must be replaced with a like relief valve.
7.2 Thermostats and Temperature Limiting Device
The temperature limiting device and thermostat temperature sensors extend into the water in the tank. Depending on
the water conditions in your area, scale may coat the sensors. This coating will affect accuracy of sensors and can
allow water temperature to exceed the desired limits. Remove and inspect these controls at necessary intervals.
Remove scale if present.
7.3 Control Valve Actuator
The boiler water control valve actuator is sealed and requires no maintenance. Durability of valve stems and packing
is dependent upon maintaining non-damaging water conditions. Inadequate water treatment or filtration can result in
corrosion, scale, and abrasive particle formation. Scale and particulates can result in stem and packing scratches
and can adversely affect packing life and other parts of the hydronic system. Contact the manufacturer for
replacement packing and stem & plug assembly.
7.4 Tank
Depending on water quality and operating temperature, scale can form during operation and will accumulate on the
bottom of the tank. Natural minerals in water forms scale, which precipitates out during the heating cycles.
Some water supplies contain more of these minerals than others, so scale buildup will occur more rapidly.
Other factors affecting the scale buildup are the amount of hot water used and the temperature of the water.
The more hot water used the more fresh water containing the scale-forming minerals come into the tank. As the
temperature of the water increases, the rate of scale deposited also increases. The frequency of inspections will be
determined by the rate of scale buildup. Until the appropriate inspection and cleaning frequency is established,
inspect the tank every six months or more frequently if higher scaling conditions are present.
Flush the tank at the appropriate interval, based on water conditions in your location, to help prevent the
accumulation of scale.
To flush:
turn off the electrical disconnect switch to remove power and prevent the unit
from operating. Open the drain valve and allow water to flow through the tank until it runs clear. Close the drain
valve and turn the electrical switch back on.
NOTICE:
Since PVI cannot control the use of the appliance, water conditions, or maintenance, the warranty on the
appliance does not cover poor performance, structural failure, or leaking due to an excessive accumulation of scale.
a. If the unit requires shut down, remove all power from the system. Close all boiler water and cold water supply
valves to the unit.
b. If the unit is removed from service for an extended period of time, it must be drained completely to reduce the
risk of freezing, biologic growth and corrosion from stagnant water conditions. When the appliance is returned to
service, conduct a thorough inspection of all utilities and general appliance condition.
7.5 Cleaning the Heat Exchanger
1.
Do not
open until all pressure is removed, the unit is drained and the equipment surfaces cooled to ambient
temperature.
2. Heat exchangers subject to fouling or scaling should be cleaned periodically. A light sludge or scale coating on
the tube greatly reduces its effectiveness. A marked increase in pressure drop and/or reduction in performance
usually indicate cleaning is necessary.
