Vaillant No Hot Water

[isaac624]

I posted this a couple of days ago and it did fix the problem for 24 hours. The post can be found here: //www.diynot.com/forums/viewtopic.php?p=1629768#1629768

I have a Vaillant urbomax Plus 824E Combination Boiler. It was showing 0 pressure but now is staying at 1 bar (in the green and good). We were getting constant hot water for 24 hours and now, it is cold. I will mentioned that this morning when I took a shower, it was nice and hot and I never noticed a drop in temperature (even on the boiler). And every time we noticed this issue, it always seems to be at night.

I checked that the boiler is suppose to always be running (on the middle dial with the burst symbol). I am not getting any error codes and check everything that I possible can think of. Water will come out when we turn the hot dial, but it will be cold.

The only thing I can see that sounds weird is that when I turn the boiler off for a minute and turn it back on, hoping that it will fix, I can hear it running and then after a minute, stop. The green light is still on, and the smaller green light is blinking. Does anyone know what I can do to fix it?

Thank you in advance for any advice you can give.

Kindest Regards

Andrew

Pictures of the boiler is shown below:

Untitled

• isaac624
• 31 May 2010
• 2

[

Untitled

• isaac624
• 31 May 2010
• 2

 

[Agile]

Does it work on CH ?

If it does then i would ask you to check the DHW flow turbine.

However, you have already said that you are not a DIY person and working on boilers does require some skills.

You may need to call a competent boiler engineer.

Tony

 

[isaac624]

Agile,

You are right, I have never worked on a boiler. But I am good at fixing things (Computers and their hardwares). If I have instructions, I can follow it and fix nearly anything. I am unable to call anyone to fix it due to funds and will have to wait till next month till I will have the funds anyway. Please, if you can give some instructions, that would be appreciated. I have guest coming one week from today and would like to fix it before they come.

Kind regards.

Andrew

 

[ianniann]

Sounds like you're finding some of the real problems now Probably you've already found something that will need fixing by a professional, but you can run some checks to give you an idea what things are wrong.

When you run the hot tap, does the boiler fire up and for how long? I think you already answered this. Do any radiators get warm when you run the hot water? Do any of the pipes coming out of the bottom of the boiler get warm? Try turning on the heating and then see if you get hot water.

I think the blinking green light on these boilers indicates hot water demand is detected? Of course it depends which green light is blinking!

 

[isaac624]

ianniann,

When I turned on the hot tap, it does sound like the boiler is turning on during the entire duration but it is not heating up the water. I tested this a second time and it did not switch on the boiler this time.

None of the radiators are heating up.

None of the pipes coming out of the bottom are warm.

I did try turning the heater off than back on, and it would warm up some, but not enough to get hot water. (the boiler showed that it went from 18 to 19). When I switch it on, it sounds like a fan is working for 40 seconds and then stop.

There are four lights I can see, three small ones (red, yellow, green) from left to right. Then there is one big green light that shows if the radiator is turned on or off. The small lights, I know the yellow turns on when the boiler is heating up the water, but even when I turn it off then back on, this light no longer turns on.

I think it is something to do with the actual device that heats the water but thought that there should be some type of error code if it was this (what else would the red light be).

Thank you ianniann for helping.

Andrew

 

[isaac624]

Ok. I just checked the boiler again, and it is now 54 degree (it was showing 18 degrees two hours ago). I do not understand since I left it on all night and it never moved from 18 degrees. Can someone let me know what is going on?

I have three settings on the dial, one that looks like a crescent moon (which I believe means it only runs during day or night), a burst, and a timer. I have it set on the burst which I thought means run when needed.

Does anyone have any explanation?

 

[ianniann]

The red LED means a boiler lockout if it is lit. The yellow one means the burner is lit. The green one means that the "warmstart" function is on, or if flashing means that hot water is being demanded. Warmstart fires intermittently to maintain hot water for immediate use. Your warmstart appears to be on. The warmstart can be switched off by turning the hot water temperature control all the way to the left and then back to its normal position, which might make troubleshooting a bit simpler. You can turn it back on by turning the knob all the way to the right and then back,

So when you run hot water, the yellow light should be on and the green light should be flashing. If the green light doesn't flash then the boiler isn't detecting the hot water running, which probably means the flow sensor is knacked.

The three settings on your controller are: crescent moon for heating off, shining sun for heating on, and clock symbol for timed heating. You appear to have the heating set permanently on. I presume it is being controlled from elsewhere, perhaps a room thermostat? The big light above that knob doesn't really mean anything except that the boiler has power.

 

[isaac624]

ianniann,

Thank you for your explanation of what each light and symbol means. that is very informational, and more than I ever knew. The strange thing is that the green light is flashing even when the hot water is not running and when the hot water is running. The strange thing about the boiler is that earlier today, it was working for a while and now it is not working again.

What I would like to know, where I can check to see if it is really working or not, is how can I turn it on and leave it on permanently? We only use the boiler right now for the hot water (doing the dishes and showers). We do have a thermostat but that is for the radiators. And should we turn it to the crescent moon when we are not using it and the shining sun when we are?

Sorry if these questions are consider stupid, this is the first time I have ever used a boiler before and would like to get as much information as i can. I just want to ensure that the wife and I have hot water when we need it and for as long as we need it.

Thank you again ianniann for helping.

 

[ianniann]

The green light may flash from time to time because of the warmstart feature. That's why I suggested turning it off for the time being. If it flashes all the time then that's a problem, although I don't know what would cause that.

If the boiler is on then the hot water is on. When you run the tap it heats the water. You don't need to do anything else. The dial on the left controls how hot the boiler will attempt to make the water. This is a maximum and if you are drawing water faster than the boiler can manage then it will be cooler than that maximum temperature.

If you don't want any central heating, turn the knob to the crescent moon. The heating will be off permanently until you move the knob to a different setting. The hot water will (should!) continue to work.

 

[isaac624]

ianniann

I am going to keep an eye on it for now. I switched the settings to the crescent and moved the temperature to only 3/4 full. As of now, it seems like it is working, but I am not for sure. Thank you for your help, and if it does stay working, I will come back on and thank you again. Right now, it seems the boiler only works when it wants to work.

Two months ago, we had no problems and we have not touched the boiler settings before we started having the problems. That is why I am confused on why it is doing it now.

 

[Bunnyman]

If serial number u found previously near the model number starts 002 it's a faulty air pressure switch known problem it's at top right hand side at back u don't need to remove case if it's black about 3 inch square change it Agile whats a flow turbine !! Lol

Untitled

• Bunnyman
• 26 Mar 2010
• 499

 

[ColJack]

those pics show the boiler pressure at 0.. are these a pre-fix picture?
if they are then we need up to date picture since the settings may be different..
if not then the lack of pressure might have something to do with it..

and OP, if you furnish me with your e-mail then I can send you a PDF of the manual..
just put your e-mail as a comment on my profile or yours..

 

[Agile]

Dont Vaillant call their DHW demand device a "flow turbine"? Thats when its not in German as einwasserwantenthinginswitcher

Its generally similar to the one used on their Heatline boiler! Ha Ha

Tony

 

[isaac624]

These pictures were post fixing. I will put up new pictures later today when I get back home. I have not seen any problems since switching to the crescent moon and lowering the hot water flow. I do not know if that really fixed it but it seems to be working.

ColJack, I put my e-mail address as a comment on your profile.

Bunnyman, I will check the serial number when i come back. Thanks for letting me know about that, I would have never known.

 

[Bunnyman]

Agile you make me chucklle its an aquasensor not a flow turbine that sounds like summat from selafield!!

Untitled

• Bunnyman
• 26 Mar 2010
• 499