REGULAR CARE
8
TEMPERATURE PRESSURE RELIEF VALVE
This valve is near the top of the storage tank and is essential for its
safe operation. This valve is designed to only relieve excess thermal
energy or an unanticipated build-up of pressure. In a fully flooded
closed loop system an appropriately sized expansion vessel must be
installed to accommodate for the expansion of heat transfer liquid. It
must be sized to accommodate the pressure of the full capacity of
the system and its thermal expansion. In a drain back design the
system is not filled to 100% of its capacity, therefore an expansion
vessel is not required. The heat transfer liquid will expand into the
remaining empty capacity of the system.
The relief valve may discharge some fluid on first heat up. Continued
leakage of fluid from the valve and its drain line may indicate a
problem with the water heater (refer to
“Temperature Pressure
Relief Valve Running”
on page 10).
Warning:
Never block the outlet of this valve or its drain line for
any reason.
Operate the easing lever on the temperature pressure relief valve once every six months. Refer to
“Minor Six
Month Maintenance”
on page 7.
It is very important the lever is raised and lowered gently.
Warning:
Failure to do this may result in the storage tank cylinder failing.
Warning:
Exercise care to avoid any splashing of fluid, as fluid discharged from the drain line will be hot.
Stand clear of the drain line’s point of discharge when operating the valve’s lever.
If fluid does not flow freely from the drain line when the lever is lifted, then the storage tank must be checked.
Phone Rheem Service or their nearest Accredited Service Agent.
The temperature pressure relief valve should be replaced at intervals not exceeding 5 years, or more
frequently in areas where there is a high incidence of water deposits (refer to
“Water Supplies”
on page 9).
Storage
tank
Drain
line
Lift until fluid
flows from the
drain line
–
lower gently
