help with ecoTEC valliant 831 and heating

[MW9]

I put boiler to no heat, and connect hose to the drain pipe on the lowest point and open air vents and let the water go down.

For the filet I isolate the 2 taps on the filter open the bottom screw yet the water drain and then I open the bottom valve (the one on the pic) and let the return water come through it and then I close it. I don’t open whole filter as apparently the o ring can go wrong on those and they can leak once open.

Should I do anything else?

This is the problematic radiator in the end I have open both caps and put hose and this is what come out in therms of the colour, don’t mind the fluffs (they are not from radiator) as the vaccun was used around the house.

 

[MW9]

This is how I drain, I have 3 of those drains on the bottom floor.

 

[Johntheo5]

Where are you flushing from?.

Unrelated query, what make/model of TRVs are installed?.

 

[MW9]

Where are you flushing from?.

Unrelated query, what make/model of TRVs are installed?.

From all of those 3 drains on the ground floor and attached is the trv but does not say what it is I think trv4 ? Or newer model they were put in 2019

 

[Johntheo5]

They do look like Drayton TRV4s, if you can use a (supplied?) key to do the balancing, they use a index 1 to 6 or something like that and are probably far easier to achive balancing with than trying to balance with the LS valve where even a 1/8th of a turn can make a big difference to the flowrate.
I presume the TRVs come set to the maximun index, otherwise maybe better to remove the heads before flushing.

 

[MW9]

not sure how they came as they were installed by Plummer so probably default setting, didn’t know you can balance on trv.

Will remove all heads for next flush, I just refilled the system and let the air out will run it for an hour before next drain

I can say when I used all 3 drain points more water came out and I spent more time on refilling and letting the air out so I’m hoping I took all the water this time

How long I can run without inhibitor? As I don’t want to waste another batch I just bought?

And if I put x800 is it ok to run it over weekend I’ve seen in the instruction it’s for 24h but seen people in reviews running it for few days just asking as I’m going away for a weekend so I can only drain it on Sunday

 

[Johntheo5]

I've no experience with chemicals but from what I've read its very important to flush and flush and flush after using say x800 as some have had hydrogen gas? forming after dosing with inhibitor, presumably because of inadequate flushing. If you do flush properly then I cant see any problem in running with no inhibitor for days on end to ensure that your cleaning/flowrates are now correct. I didn't use any inhibitor for 10 years (OV system), I throw the odd drop in now and then, some of my rads are over 40 years old with spotless water on the rare occasions I do a partial drain down for TRV renewal or whatever. I do have very soft water, maybe this makes a difference even though I never have to top up the F&E tank.

Here is the info on the Drayton TRV4

https://www.draytoncontrols.co.uk/products/radiator-valves/Drayton%20TRV4/trv4-classic

 

[MW9]

I think the x800 is design to run without as it already have protection in it, I was just wondering when I finish flushing to run a system without inhibitor for a 2 days to make sure all is good just in case i need to drain it again it will be waste of inhibitor again. its like putting £40 down the drain all the time

 

[MW9]

so after draining I'm kind of in square one, all lock shield open and all TRV heads removed and the boiler goes above the set flow temp quickly and cut off, the pump seed seems do nothing at this stage, maybe it need to run a bit longer to settle after draining, but I think I will drain again, see what water comes out and either drain again and put x800 for a weekend, and see on Monday the filter in the flow pipe if its not clogged.

if this won't help I think I will call valliant for the fix break post warranty.

I went into the test program on the boiler for the diverter valve and changed it to heating no hot water in the tap, changed it to hot water and hot water in the tap.

 

[Johntheo5]

You don't really know if it's the system or the boiler Hex is blocked or the pump isn't working or what, it might save you alot of money if you carry out what I suggested above or even simpler and probably better, buy a 0 to 3 or 4 bar pressure gauge and a lever valve and run mains water at say 0.5 bar connected to the flow pipe after disconnecting at the boiler and run the return into a container you should be able to identify pretty reasonably well where the blockage (if any) is then.

If the DHW is OK then probably not a boiler problem.

 

[MW9]

You don't really know if it's the system or the boiler Hex is blocked or the pump isn't working or what, it might save you alot of money if you carry out what I suggested above or even simpler and probably better, buy a 0 to 3 or 4 bar pressure gauge and a lever valve and run mains water at say 0.5 bar connected to the flow pipe after disconnecting at the boiler and run the return into a container you should be able to identify pretty reasonably well where the blockage (if any) is then.

If the DHW is OK then probably not a boiler problem.

ok i will flush it one more time, put x800 as I got it anyway and will wait for Monday as this is job for the engineer, if he cant sort it I will call valliant

thanks for your help if they find anything and sort it out I will report back.

 

[MW9]

so I have small update

- I have flushed the system 3 times I tried to tun boiler in between to move water around but boiler had too much air and it would take me ages so I have just refill and drain until clear water came out.

- then I have open few radiators in the entire system and put x800, instead putting in one place I thought I will add it in few radiators so it spread evenly and work on the radiators which are cold in case they are partly blocked

- I then run the system and the boiler was going up to the temp quickly again and cutting off, it was noisy as well so I google and found there is a vent on the pump you can open and run purge function and it will get rid of some air apparently this need to be done when you drain the system

- started with:
partial load 5kw and increased to up 10kw slowly when opening more rads
flow 5
pump speed 100%
2 stage function - stage 2
the temps now at this stage were more stable

- I have removed TRV's and had all the lock shield open expect one towel rain in bathroom which have **** valves and if I open them too much they leak I need to change them at next service.

- half of the radiators were getting hot and warm, I run the system for nearly 2 hours and it looked like before that I won't get all rads hot with lock shields full open, I had 7-8 rads out of 15 hot/warm , so I started closing the lock shield from the first order, and further I went I was opening a bit more, and the water was passing further so I have making notes which rads were getting warmer in next order, I had 14 rads warm/hot out of 15 and then I looked behind table and door that I forgot to remove the TRV this one , I was holding the rad on the bottom on the flow to see the difference once I remove it and as soon as I took it off the rad was getting warm at the bottom, so it does not look like the stuck PIN as the valve was on max and as soon as it was removed the rad was getting hot I didn't need to move the pin up and down with pliers. Now the valves were put in first thing we moved in before winter and we have issues since we moved in so I wonder if the link you posted about setting them up will have something to do with it as well will have to look at it and read up and see if there is any video. Before the rads had just a valve with a know + / - .

- now I was monitoring the temp and it look stable, so I changed the partial load to Auto, shut down the heating, waited for the pump to stop and went around the rads again to let any air just in case and left the heating to kick in today morning to see if I will have issues again.

and today morning rads are nice and hot, and some very warm.

I'm away for today and coming back on Saturday so I will leave the x800 till Saturday and when I'm back I will run heating for couple hours.
make note on the turns of the lock shield, open them all up fully and drain the system few times again. change the lock shield to whatever settings I made, run it for a 2 days, once everything is working I will drain a bit of water and add inhibitor


the pipe under the boiler seems warmer, the D40 shows 75 and d41 was showing 68 in the morning. so 7 difference sometimes less like 5 but the radiators seems to be working and return under boiler feels warmer.

not sure if I should experiment with the pump speed or leave it on 100% for now for the cleaning to move around.

the guy who is coming on Monday actually installed those TRV for us so I will ask him about the settings on them as well. maybe they have some limit even though they are on nr 6 or max

 

[Johntheo5]

I would suggest leaving the pump on 100% as it will/should circulate more,
The TRV on setting 6 should definitely give you the max flow available, as long as the pin is fully extending, there is a flow chart, will have a look at it later.
With the pump setting at 100% then even with the by pass at minimum, fully clockwise, it will still by pass at 3.5M so shouldnt cause a problem IMO as long as the pump remains at 100%.,

What is the boiler cycle rate now, ie burner on time vs off time?

Ask your man to to check if there is a filter on the boiler flow.

 

[MW9]

the burn time seems stable now constant 74-75, sometimes it will go to 77 but haven't seen it cut off yet every time I go and check it is burning / running, it came on while I was sleeping so on Saturday I will monitor how it is rising from the cold

that problematic radiator was 10th in the sequence now out of 15, so maybe it was partly blocked and now the x800 helped? as I had the radiators 11, 12, 13, 14 hot/warm and the 10th was stone cold

 

[Johntheo5]

Definitely on the right track I'd say.