Collant System - Skoda Octavia Scout

Quite a while back the heating in my Skoda Scout 2015 started to play up.  First one side could only blow out slightly warm, then it could only blow cold.  After a while the other side did the same.  My garage seemed to have a lot of trouble draining/ flushing the system and said the coolant had "sort of gritty" stuff in it.  The problem continued and the garage then replaced the heater matrix which they thought might be clogged.  The pump(s) seemed to be working okay as did the thermostat.  Although the heating worked after this, it wasn't great and the blower seemed to lack the power it had prior to going in to the garage.   Over the last six months or more, on a few occasions, I've heard through the dash a strange noise. Having been driving the car and turned the engine off, a gushing sound/ liquid draining sound which goes on for quite a while.  I wondered if anyone had any suggestions - surely this must be an airlock?  Note the garage told me they couldn't completely flush the system but weren't clear why.  Costs had mounted already so I hoped the problem had been solved.  Last week the alert appeared on the dash, I added some coolant and it was fine.  Now wondering if I don't take it to a specialist or Skoda garage to get the wholes system properly flushed through & a new blower motor installed too.

Edited 4 September, 20241 yr by Wildman
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