Vaillant latest 470f WC controller with latest ecotec 831 boiler

[chris watkins]

The rads are sized for heat loss at -3 usually so as the the outside temp rises the demand is less, hence the flow temp can drop and the output can reduce.

The difference with lower flow temps are the heat exchange rate is a lot slower so you can't flick the heating on at 5pm and expect to be toasty by 5.30pm if your looking to raise the room temp by 3 or 4 degrees.

Maybe try and set the off temperatures to say 19 degrees through the day and if required the boiler can top up over the day. The problem might be where you have doors opening and closing all the time and heat loss that way.

The only thing to add to Sam's post, which was more eloquently put than mine anyway, is that the old rads where probably sized on a MWTemp of 76.5deg C so to be able to get the most out of the boiler in condensing mode if new we would use max of 60 deg (& even a bit lower if there is no domestic hot water heating involved).
As you say stradtobudy I thing you are asking a lot from the new boiler it is as the say summer, Ha, Ha !! Turn the heating off & when it gets a little colder turn it back on, set it up, leave it on & don't fiddle with it (& the WC system), at least for a while.

 

[stratobuddy]

Just to explain how I got into this situation, a friend had the ecotec 831 boiler and 392f controller installed at the recommendation of her plumber.

I liked the system so I specified the same system to my plumber.

None of us knew that Vaillant had changed the boiler design (but kept the same name), and that the 392f controller would no longer work with it, AND they didn't have a compatible controller available yet.

 

[vaillant831]

I have the exact same boiler as you Stratobuddy, the same controller on order (to be delivered on the 29th) and existing rads. By the sound of things will be needing some tips. I'm assuming you can't just turn the weather sensor off (or not pair the device with the main unit)?

 

[stratobuddy]

I offered to write an article about WC heating system controllers for this forum, based on my own experience with it and lots of research into heating curves etc.

I sent a draft to Dan a few weeks ago for approval but have not heard from him since.

If you pm me with an email I could send you a copy of what I've written so far.

 

[vaillant831]

Thanks stratobuddy but I can't PM until I hit 15 posts

 

[phpaul]

sounds to me like the system would work well with underfloor wet heating

 

[phpaul]

to be honest i like to use salus controls. the new s series stuff is cool even has a service mode

 

[stratobuddy]

To Vaillant831 - - - let me know how you get on with it.

Are you installing the 470f components yourself and setting up the "installer level" parameters of the controller?

 

[radswilldo]

Just to explain how I got into this situation, a friend had the ecotec 831 boiler and 392f controller installed at the recommendation of her plumber.

I liked the system so I specified the same system to my plumber.

None of us knew that Vaillant had changed the boiler design (but kept the same name), and that the 392f controller would no longer work with it, AND they didn't have a compatible controller available yet.

I installed the new 831 at my home in June; as I write this reply I am happily gazing at my 392f, which is sat pretty on a wall. Who has said that the 392 is not compatable? If you look at Page 13 in the manual it plainly states that the 392f is one of the accessories available. What you cant do with the 392f, as opposed to the 470f/350, is plug the reciever unit into the new boiler's facia.

 

[keentoknow]

Hi, we too have this timer and mostly it is ok but when the weather gets really cold it struggles to reach the desired temperature for hours and sometimes never does. I think I read somewhere that the boiler itself needs to be set to maximum but our plumber is insisting it should be at 72%any help you can give me would be great, the thing is a mystery to me

 

[chris watkins]

I don't know the 470F in particular but with WC systems in general (& especially in older less well insulated dwellings) this can be a small problem there are two choices - one is leave the heating system on for longer so the structor is allowed to heat up or even stay up to temperature.
The second is to increase the ramp setting manually (on mine this means simply increasing the boiler thermostat setting) I only do this while it is very cold & return it back when it rises, this will have the effect of increasing the water flow temperature against the outside air & will improve the warm up times. (you can leave it at this higher setting if it is not heating correctly) I feel this is a small price to pay for the savings delivered.

 

[keentoknow]

Thank you for your reply Chris, yes we are going to try to increase the thermostat on the boiler,we will just have to wade through the instruction book to find out how. I am determined to understand the timer but my husband wants rid of it.

 

[dancinplumba]

Thank you for your reply Chris, yes we are going to try to increase the thermostat on the boiler,we will just have to wade through the instruction book to find out how. I am determined to understand the timer but my husband wants rid of it.

hi, with the 470, your boiler stat should be at maximum, its the 470 which decides what boiler flow temp is.

 

[dancinplumba]

and temp dial is on front of boiler 🙂

 

[keentoknow]

and temp dial is on front of boiler 🙂

Yes I read this on this thread that the boiler needs to be on maximum but when I asked the heating engineer he said he likes to set it just below maximum so its not working at full blast, Can you explain to me in simple terms why this should solve our problem? We are both really useless as technical things

 

[dancinplumba]

he is right if its a simple on/off stat, but its not. if room very cold, stat tells boiler to output high temp water to heat room quicker, but it carnt if boiler not set on maximum. when temp in room gets near to set temp, stat tells boiler to reduce heat output. 🙂
Does the radiator in the room where you have your stat have a thermostatic valve on ?

 

[keentoknow]

he is right if its a simple on/off stat, but its not. if room very cold, stat tells boiler to output high temp water to heat room quicker, but it carnt if boiler not set on maximum. when temp in room gets near to set temp, stat tells boiler to reduce heat output. 🙂
Does the radiator in the room where you have your stat have a thermostatic valve on ?

Yes we have a thermostat on the hall rad which is where the controller is , we can't find out how to turn up the boiler in the instructions , its a vaillant ecotec pro is turning it up dufficult? Is it something the engineer has to do?

 

[dancinplumba]

and temp dial is on front of boiler 🙂

as above !!, you need to remove stat on rad as it is not helping. also get an engineer that knows what they are doing ? your 470 needs the heat curve etc set up

 

[keentoknow]

as above !!, you need to remove stat on rad as it is not helping. also get an engineer that knows what they are doing ? your 470 needs the heat curve etc set up

We don't have a dial on the boiler there are plus and minus buttons. We have the heat curve set to 4(max) .it is all fine till the weather gets really cold.I have emailed Vaillant but they did not reply.i can't get through on the phone either.

 

[dancinplumba]

heat curve should be 2 in this country, my bad thought was plus not pro. you have to go to page 13, 5.2.2 then 5.2.1 and do what it says in your instruction manual, if you dont feel confident get an heating person thats knows what they are doing 🙂 Put a post up in forum plumber or gas installer wanted.
ps: there is a thanks button in bottom left, feel free to press it 🙂