baxi 150e combi boiler instant luke warm hot water

[desrob]

this model has the pre heat function,when i turn pre heat to the off position the boiler fires goes to 80 degrees knocks off for say 20 seconds and relights again and this gives me luke warm water,when i try to turn pre heat function on the boiler knocks off straight away,this is of course when running the hot water tap any ideas

 

[aggis]

Check dhw thermista readings,10-14kohms cold. then would be looking at a blocked water/water heat exchanger if the temp is topping out.
Worth checking baxi technical out, if not thermistas. 08448711555

 

[desrob]

how do i check resistance and what setting do i have the multi meter at i'm confused when your refering to what i think is kilo ohms

 

[oldplumber]

If your gas safe this simple check should be second nature for you, if your not qualified you shouldnt be messing with the boiler as your messing with safety devices and thats a no no. If your an apprentice, get your boss to show you, thats what they should be doing to teach you what to do.

 

[desrob]

yes i am an apprentice,and i do know how to check for resistance, continuity ,just he confused when he mentioned K ohms,my boss does show me,i'mjust doing my own bit researching etc,and i totaly agree,if your not qualified and competant do not mess about with gas fired boilers,can i approach you in future research a different take on things you might say

 

[Toddyplumb]

You do not know how to check resistance ! You said so yourself. Get your boss to show you again