National Oilheat Research Alliance 41
size and the water temperature in the boiler
must be considered. Figure 12 below.
Piping and Maintenance
Recommendations
The following guidelines should be followed
in addition to the manufacturer’s specific
recommendations, unless the manufacturer
recommends otherwise.
• When installing a new unit, all piping
should be new
copper with a
minimum number
of elbows.
• When piping
direct and indirect
water heaters, it’s
a good practice to
install a heat trap
as shown in Figure
13 to reduce
standby losses.
• All piping
should be checked
for leakage at
joints, valves and
unions on an annual
basis.
• The temperature & pressure relief valve
should be checked for proper operation on an
annual basis as follows:
Attach a drain line to the valve and
direct the water discharge to an open drain
(the water will be HOT!)
Lift the valve lever several times and
ensure that it operates freely and returns to
its original position. If the valve does not
function properly, replace it.
Figure 11
Figure 12