Rear Heater Blowing Cold Air

[Ian]

Can anybody help Iain? He's based in Glasgow.

I've recently had my coolant drained, refilled and bled, the trouble is that the front heaters work fine but the rear heater blows cold air, the garage I use have repeatedly tried to bleed the system but to no avail, any suggestions, thanks

[wonkanoby]

fee lthe 2 hoses from underneath

both hot or just one,if one its blocked and needs back flushing

if both it may be the links etc that control it

[Northern Bongolow]

the rear heater is just about the lowest point in the system so any floating solids tend to collect here, its always worth removing both pipes and flushing it through to make sure the through flow is good. during the flush out process you could also remove one pipe at a time to make sure the supply and return is flowing well too. be aware the stubs to the heater are very brittle plastic so dont swing on them.

if all seems well during the flush it could just be an air lock put there during the fill up , sometimes its necessary to loosen a pipe to bleed out the air as the supply and return are at the bottom of the heater matrix, this will allow the trapped air in the matrix above to exit easily.

[rita]

Might sound stupid but...is the rear heater control set to Hot.?