Oil flow to tiger loop

[BRJ]

Our burner locks out. The oil flow coming into the tiger loop appears too slow to keep up with pump demand and so it runs out. If left for a few minutes the oil level in the tiger loop builds up and allows the boiler to fire again but only for a few minutes. This occurred for the first time 4 days ago at a coincidence of (1) a delivery of fuel was made, we hadn't run out and (2) following a week of outside temperatures of - 5 to -12 C. The temp outside has now been + for a couple of days. Any ideas ?

 

[verdigrey]

If the boiler was running when the oil delivery was pumped into the tank it could have stired up water / dirt from the tank bottom and been sucked into the filter and water can also go past the filter and into the pipe going to the tiger loop . This can then freeze and reduce the flow of oil to the boiler .
Try cleaning the filter out or pouring a bucket of hot water onto the filter and pipework and see if it helps .