Vaillant turbomax 824e dhw fluctuates hot & cold
Hi
I was wondering if anybody can advise about a problem that my parents are having with their boiler. When you open the DHW tap the boiler fires up and you get hot water (the temp on display climbs into the late 80's then the boiler switches off (not complete switch off - i.e. is not fired up) water temp drops to lukewarm and display drops to 40's then fires up again and continues this cycle whilst the DHW tap is open. DHW temperature selector has no affect on water temp. at any setting.
The system is pressurised to the correct setting (in the green just above the no.1)
The diverter was replaced 8 mths ago because it was leaking (unrelated to above problem).
The flow rate is at 7 litres p/m.
The CH works fine and the checks mentioned regrading the DV mentioned in other threads do not point to the DV (leaving heating off and checkin if rads warm up on DHW demand). when the DHW tap is opened whilst CH is on the same problem persists.
The boiler is at my parents house who are pensioners. they have had some engineers out but the advice/causes ranged from :-
(1) Thermistor (£90)
(2) DHW Heat Exchanger (Secondary) (£175) + A TF1 Filter (£120)
(3) Gas Valve (£150)
(4) PCB (£225)
(5) Divertor Valve (even though its already been replaced) (£130).
(6) PowerFlush to clean the heating system (this will not solve the problem but is beneficial to have done one guy said (£450 + VAT)
Not going to attempt to fix myself but wanted to know which cause is the most likely problem and I will go with getting that fixed first.
Or should I just buy another boiler ? (not ideal but its probably cheaper for my parents with some of the quotes above).
turbomax 824e installed 5 years ago through a heating grant.
Thanks and regards
Jonathan
Hi
I was wondering if anybody can advise about a problem that my parents are having with their boiler. When you open the DHW tap the boiler fires up and you get hot water (the temp on display climbs into the late 80's then the boiler switches off (not complete switch off - i.e. is not fired up) water temp drops to lukewarm and display drops to 40's then fires up again and continues this cycle whilst the DHW tap is open. DHW temperature selector has no affect on water temp. at any setting.
The system is pressurised to the correct setting (in the green just above the no.1)
The diverter was replaced 8 mths ago because it was leaking (unrelated to above problem).
The flow rate is at 7 litres p/m.
The CH works fine and the checks mentioned regrading the DV mentioned in other threads do not point to the DV (leaving heating off and checkin if rads warm up on DHW demand). when the DHW tap is opened whilst CH is on the same problem persists.
The boiler is at my parents house who are pensioners. they have had some engineers out but the advice/causes ranged from :-
(1) Thermistor (£90)
(2) DHW Heat Exchanger (Secondary) (£175) + A TF1 Filter (£120)
(3) Gas Valve (£150)
(4) PCB (£225)
(5) Divertor Valve (even though its already been replaced) (£130).
(6) PowerFlush to clean the heating system (this will not solve the problem but is beneficial to have done one guy said (£450 + VAT)
Not going to attempt to fix myself but wanted to know which cause is the most likely problem and I will go with getting that fixed first.
Or should I just buy another boiler ? (not ideal but its probably cheaper for my parents with some of the quotes above).
turbomax 824e installed 5 years ago through a heating grant.
Thanks and regards
Jonathan