The 75 and ZT Owners Club Forums - View Single Post - Heater Matrix

T-Cut · 20th September 2018, 08:33

I'd suggest that the matrix is quite blocked up, in spite of your observations. These are good, but your conclusions are uncertain. The question is coolant flow rate through the complete matrix. Its design has lots of pipes in parallel, left to right, so with a large part of these blocked, there will still be a reduced flow. Certainly enough to pass your 'blow though the pipes' test. This also explains why the outlet hose is significanntly cooler than the inlet. I therefore suggest trying a hosepipe backflush through the matrix to remove any loose detritus. If that doesn't fix it, you may have to replace the matrix. Some people have descaled it using chemicals.

TC

20th September 2018, 08:33	#2
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	I'd suggest that the matrix is quite blocked up, in spite of your observations. These are good, but your conclusions are uncertain. The question is coolant flow rate through the complete matrix. Its design has lots of pipes in parallel, left to right, so with a large part of these blocked, there will still be a reduced flow. Certainly enough to pass your 'blow though the pipes' test. This also explains why the outlet hose is significanntly cooler than the inlet. I therefore suggest trying a hosepipe backflush through the matrix to remove any loose detritus. If that doesn't fix it, you may have to replace the matrix. Some people have descaled it using chemicals. TC Last edited by T-Cut; 20th September 2018 at 08:36..