BAXI Combi 105e DHW Problems!!!

[matt_t586]

HI, the problem is that when we run a hot tap the boiler fires up and everything seems ok and the lights indicating temp rise as normal, however when it gets to 50 degrees the flame goes out and only kicks back in when the water is almost stone cold!! thaen it stops at 50 again! the thermostat is turned right up! Please help!, i have had the temp sensor out and cleaned it but it hasnt helped!

 

[bripl]

try the filter in the return,bottom rhs in the isolating valve prob full of dirt.

 

[ollski]

No point cleaning the sensor if it is out of range, would be worth replacing it for a tenner or so before you embark on the bigger possiblities (or test resistance @ given temperatures if you can)

 

[matt_t586]

Clean as a whistle!! also what would the HTG return have to do with my
hot water!!!!?

 

[Terrywookfit]

Could be plate heat exchanger full of crap!!
Quick job to check.

 

[baxpoti]

Plate heat exchanger is probably contaminated.

 

[BOB D.O.L.E]

Could be plate heat exchanger full of rubbish!!
Quick job to check.

What way would yea do it tho terrywookfit for this so called quick job check.

 

[bripl]

Clean as a whistle!! also what would the HTG return have to do with my
hot water!!!!?

if the filter was clogged/blocked fair chance your plate he is dirty so no transfer of heat .that is your problem is it not?

 

[matt_t586]

THe filter was clean spotless even! i dont know the problem other than im not getting hot water!!!!

 

[Agile]

You would need to do a thermal survey on DHW to see if the plate HE is blocked.

I have seen one which LOOKED clear but did not allow any water to flow throught it.

Has the pump impeller been checked???

Tony

 

[Terrywookfit]

Could be plate heat exchanger full of rubbish!!
Quick job to check.

What way would yea do it tho terrywookfit for this so called quick job check.

Turn off supplies> Drain and remove. (10 mins).
I have personally never encountered one that shows no sign of problems as Agile suggests!!!
I generally find "Tea leaf" type deposits in the primary water side!
Sometimes a quick reverse flush will get it operating again.
I carry a selection of units for replacement which i then powerflush when doing an installation!! (OR rather my assistant does).10 mins with a dose of FX2 and they are like brand new
Installers in Antarctica tend not to powerflush but I have also found this problem on properly flushed and inhibited new systems (MY OWN)