Page 136 - Webster Service Manual

Vacuum coming from return port on oil pump
two pipe installation)
By-pass plug not installed
If by-pass plug is installed check for blocked
suction line
Pump seizes at start-up. blows seal. damage
to discharge pressure gauge
Check for blocked return line or drain port from pump
By-pass plug should be removed on single pipe
Supply Unit does not run
Check motor electrical connections
Check for obstruction in return line such as a reversed
check valve
Check circuit breaker and correct possible overload
Unit runs. but no oil reaches supply pump
Measure suction inlet vacuum, should not exceed
in. of vacuum
Check that all plugs and suction line connections are
Be certain by-pass plug is in position
Use adequate size suction line
Be certain suction line filter or strainer has adequate
Unit supplies oil to distribution system, but no delivery
of oil at OSV valves
Confirm specified unit can provide needed vertical
discharge pressure
Check that all supply line connections are air and
oil tight
Use adequate size supply line
Minimize supply line restrictions
Prime pump and purge supply lines of air
Check pump pressure settings
Oil delivery at OSV valves. but burners do not fire
Confirm specified unit can provide needed capacity
Size to firing rate for single pipe burners or size to
gear set capacity for two piped burners)
In pressurized system, adjust pressure to develop a
reading of 10-15 PSI at the most remote or highest