baxi 80e intermitent hot water

[Wayne Singleton]

hey guys .... and girls just in case !!

i have a baxi 80e boiler which is a few years old now. the problem is the hot water.
it fires up to start with then when it gets up to 70 the flame drops to a low flame then the temp falls but the flame stays on a low flame.
having scored the forums for a while i have removed and clean the small plate heat exchanger from the back of the boiler, also the diverter valves have been cleaned out. i just tried changing the PCB today but still the same. is there anything else you can suggest i try ???

thanks for your help in advise ..... am getting sick of having cold showers now !!!!

wayne

 

[mickie]

before we start, whats your gas safe number ? thanks

 

[Puddle]

was there much rubbish in the plate heat exchanger when you took out ?

what did you clean it with ?

 

[rjscan]

hey guys .... and girls just in case !!

i have a baxi 80e boiler which is a few years old now. the problem is the hot water.
it fires up to start with then when it gets up to 70 the flame drops to a low flame then the temp falls but the flame stays on a low flame.
having scored the forums for a while i have removed and clean the small plate heat exchanger from the back of the boiler, also the diverter valves have been cleaned out. i just tried changing the PCB today but still the same. is there anything else you can suggest i try ???

thanks for your help in advise ..... am getting sick of having cold showers now !!!!

wayne

Try the DHW thermistor Its cheap and easy to change ,Otherwise its the modulator thats at fault possibly

RJSCAN

 

[diamondgas]

HEy Wayne :rofl: Spent a lot trying to repair something that may just be a £10 stat!!! :rofl:

Sometimes it pays to get the experts in my friend ... hehe!

Could well be other than the stat but what lead you to change the PCB? That's usually the last thing to be at fault when ya showers pants! ..

 

[Wayne Singleton]

mickie
wasnt aware i needed to be gas safe not touched anything gas only water side of things.

puddle.
there was a little bit of small black bits that came out when i cleaned it but not too much. i took it out and back washed it with hose pipe in all 4 holes. is this enough ???

rjscan
is the thermistor the small plug type with small connector on it ??
modulator is that the gas modulator ???

 

[Billy Bob Bob]

flow pipe getting very hot in hot water mode?

 

[Wayne Singleton]

yes gasman getting hot more than water pipe is !!!

 

[Billy Bob Bob]

your divertor has failed probably due to age or a blocked plate heat exchanger i would replace both if cleaning has not worked

 

[Wayne Singleton]

have read a few forums and a few suggest if cleaned out phx and diverter working ok then COULD be PCB.
bugger on me i guess

 

[Wayne Singleton]

can the diverter be fixed with a daiphram kit or is it full part ???

 

[Billy Bob Bob]

full part the safety springs gone causing it to dump down the flow you can not buy this part separatly note the plate heat will more than likely have caused this fault other things that can cause this are faulty mixer taps or showers

 

[Wayne Singleton]

ok thanks for the help.
the shower and mixer taps have all been in since the boiler was fit so i guess they are ok !!!

 

[diamondgas]

Wayne I totally respect gas man's direction for you... However can I just verify that you knew what he meant when he asked about "flow pipe geting hot"! I believe he's refering to the radiator flow pipe coming out of the boiler. Is this the one you understood it to mean? If yes, fare enough. If no then have you replaced the hot water sensor? You'd expect the light sequence to get up to 90!

Just checkin as it could save you a boat load ....! IMO

 

[Wayne Singleton]

hey diamondgas
yeah i got what he meant and yes it is the flow pipe for ch that is getting hot the heat lights only get to 70 then the flame dies down and water cools off

wish it was a sensor been looking online for parts not cheap !!

wayne

 

[diamondgas]

Considder renewing Wayne ... If you've got muck probs they also stem to the main heatex too as well as pump etc. Boiler must be over 10 years old now I'd guess... Problem is once you've starte replacing parts you feel like you've got to fix it!!! LOL ... Good luck and let us know how you get on eh?

gas man has you in the right direction however.

 

[Paulgasman]

From whats been said. CHECKS:
1. Resistance on DHW thermister
2. Is the flue clear?
3. Divertor valve as flow pipe should not be getting hot in hot water mode
4. PCB as this works together with the fan and gas valve modulation.

BUT FIRST-----Below info is from the manual
BELOW B

1. Check the burner setting pressure ofthe gas valve

2. Voltage at modulating coil of gas valve is:

Max. burner press.approx 9V DC (13V DC LPG) YES-----------------------------Replace gas valve​

Min. burner press.approx 1V DCCurrent at modulating coil of gas valve is: NO--------------------------------Replace PCB(Use an instrument with average function for this
measure)​

​

​

30 ÷ 230 mA DC (45 ÷ 310 mA DC LPG)

​

​

​

​

 

[diamondgas]

Hi paulgasman - welcome to the forum

There's a spot for newcommers if you're interested in introducing yourself ....

Regards your post ... The perp is not Gas Safe so we're limited to the info we can offer that they may be able to interpret! And of course weary of safety regarding DIY repairs!

This is a good place to ged heads together and share experience however ... Go to the newcomers if you wish and introduce yourself

 

[Paulgasman]

I get your point diamondgas regarding the info/DIY, it make sense.

 

[rjscan]

mickie
wasnt aware i needed to be gas safe not touched anything gas only water side of things.

puddle.
there was a little bit of small black bits that came out when i cleaned it but not too much. i took it out and back washed it with hose pipe in all 4 holes. is this enough ???

rjscan
is the thermistor the small plug type with small connector on it ??
modulator is that the gas modulator ???

yes its screwed into the DHW heatexe, and yes the gas modulator ,Thats unlikly but possible

RJSCAN

 

[RoryD]

mickie
wasnt aware i needed to be gas safe not touched anything gas only water side of things.

puddle.
there was a little bit of small black bits that came out when i cleaned it but not too much. i took it out and back washed it with hose pipe in all 4 holes. is this enough ???

rjscan
is the thermistor the small plug type with small connector on it ??
modulator is that the gas modulator ???

Unfortunately Wayne, that's a complete fallicy, You simply cannot work on any Gas Appliance without the training and quals, you can be injured, killed, kill others and....fit totally unnecessary parts costing you a fortune. Honestly mate even qualifieds make mistakes

 

[mickie]

yet people are helping him out? he may have only touched the water side but thats all he's telling us..

anyone ever took a 80e apart before, ? if you have you'd know to get the diverter valve out you have to take the side panel off, and that makes it illegal.. he could end up killing him self due to the help off here and his incompetence

 

[Billy Bob Bob]

its not illegal to touch the water side its up to the op to prove there competency

 

[mickie]

what im saying is to get that valve out you have to take the side panel off, which opens up the whole boiler

 

[Wayne Singleton]

hey guys thanks for all your help.
i got a new diverter valve today and managed to replace quite easy ...... the side panel does not need taking off just the front panel. and thanks for a vote of confidence .... you think i would even be on here asking for answers if i couldnt do the job just because some people might not be able to do it please dont think we are all like that.

anyway to the point ..... it still does the same thing gets up to 70 flame goes small water goes colder and doesnt get warmer till you shut off the tap and start again

any more ideas ????