Central Heating Pump And Oil-Fired Boiler With A 13A Fcu?

[callcom]

I was looking to install a room thermostat (which needs a 3A fuse) and therefore checked the fuse rating in the FCU for the boiler and pump, to discover it's 13A. I always thought it should be 3A, though some say for an oil-fired boiler, which has an oil pump, it should be 5A.

The system has operated without problem for the last 17 years......

Would appreciate any suggestions. If it should be 5A then I need to add a 3A FCU just for the room thermostat - obviously if 3A then could use existing FCU.

Many thanks

 

[ProDave]

A 3A fuse will be fine a boiler and pump won't draw more than that.

Just a case of the manufacturer of the thermostat covering their nether regions.