What's wrong with my Vaillant Ecotec Plus boiler?
- Thread starter MaryJane7
- Start date
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Thanks for the recent postings - I'll now try and answer any queries raised!
The boiler is a Vaillant Ecotec418
I followed Agile's instructions on how to find out the boilers maximum heat output (d0 setting) and found out that the value is already set at 18
Yes, Dave, it was the main HE that the Vaillant engineer replaced
As this is my first ever forum, I hadn't realised the importance of the 'location' box so I just put my birth county. Sorry. In actual fact I now live in Cambridgeshire, and the Vaillant engineer came from Peterborough. Hope that's cleared that one up!
The boiler is a Vaillant Ecotec418
I followed Agile's instructions on how to find out the boilers maximum heat output (d0 setting) and found out that the value is already set at 18
Yes, Dave, it was the main HE that the Vaillant engineer replaced
As this is my first ever forum, I hadn't realised the importance of the 'location' box so I just put my birth county. Sorry. In actual fact I now live in Cambridgeshire, and the Vaillant engineer came from Peterborough. Hope that's cleared that one up!
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D
Deleted member 105431
I would also try downrating it to 14/15 kw and ensure the flow and returns aren't crossed.
I know this will be of no help to the OP, but these boilers seem to be a problematic model, was the older ecoMAX pro any better, would you ever fit one?
I've had this give the S98 code when they are the wrong way round
Found out when I power flushed the boiler with it running hot. This ocurred every time I reversed flushed the HE
Ok, I'm just about to (a) turn the pump speed up from 2 to 3 (thanks Dave) (b) downrate to 15 kw (thanks dangermouse46).
Will report back tomorrow!
Will report back tomorrow!
Your previous boiler was 12 kW and that may have been over rated.
Based on that I would suggest you set the power to 12 kW which will result in marginally increased efficienct and further reduce the chance of spurious errors.
You could always increase it later or if there is a severe cold spell now that you know how easy it is.
Tony.
Based on that I would suggest you set the power to 12 kW which will result in marginally increased efficienct and further reduce the chance of spurious errors.
You could always increase it later or if there is a severe cold spell now that you know how easy it is.
Tony.
Thanks to the helpful suggestions on yesterday's postings, I've been experimenting as you've suggested and have made quite a bit of progress today!
First thing this morning (with the pump up to level 3 and d0 down to 15) I turned on the central heating system without the hot water system and it worked! No S.53 message, just normal operation. Really chuffed!
I'd put the central heating on for an hour. It took about 20 minutes to get up to maximum water temperature of 68C. An hour after it had switched itself off, I tried for another hour of heating. Dash. S.35 message.
I then took Tony's advice and tried turning down d0 still further, to 12 this time. Once again I was able to turn on the central heating system without the hot water system and everything worked. Wonderful.
Now I tried monitoring what would happen when the room temperature reached the level set by the room thermostat. The central heating went off as expected (S.30) which was all well and good, but then when the room temperature dropped and it should have started again then S.35 came up. This was displayed for 10 minutes and then the boiler got going again and stayed Ok.
I've tried turning d0 down even further to 10, but strangely the S.35 message comes up straight away then.
Wonder if anyone has any more thoughts? It looks like the problem is definetely lessening!
Perhaps I should say bit about my radiator settings? This might be totally irrelevant but you never know.
Well, I live in a small three bedroomed terrace. Two bedrooms have their TRV's on 'frost', which means they came on this morning but then turned themselves off after about 30 minutes. The box room TRV is 1.5 and the bathroom is 6. Downstairs the living room radiator is fully open, hall on 3, kitchen on 3 and conservatory on 'frost'.
Just to give you an idea of the area I'm trying to heat, and when, I've been round with the measuring tape today and have worked out that the total radiator area for the whole house is 5.26 sq m. First thing in the morning all these radiators initially heat up. When the radiators with low TRV's shut off, the total radiator area remaining is 3.14sq m.
I'm sorry this is such a long posting but I was so encouraged by today's progress that I thought it was worth giving you all the information that I had to see if anyone has any more ideas. Thanks for reading this for me.
First thing this morning (with the pump up to level 3 and d0 down to 15) I turned on the central heating system without the hot water system and it worked! No S.53 message, just normal operation. Really chuffed!
I'd put the central heating on for an hour. It took about 20 minutes to get up to maximum water temperature of 68C. An hour after it had switched itself off, I tried for another hour of heating. Dash. S.35 message.
I then took Tony's advice and tried turning down d0 still further, to 12 this time. Once again I was able to turn on the central heating system without the hot water system and everything worked. Wonderful.
Now I tried monitoring what would happen when the room temperature reached the level set by the room thermostat. The central heating went off as expected (S.30) which was all well and good, but then when the room temperature dropped and it should have started again then S.35 came up. This was displayed for 10 minutes and then the boiler got going again and stayed Ok.
I've tried turning d0 down even further to 10, but strangely the S.35 message comes up straight away then.
Wonder if anyone has any more thoughts? It looks like the problem is definetely lessening!
Perhaps I should say bit about my radiator settings? This might be totally irrelevant but you never know.
Well, I live in a small three bedroomed terrace. Two bedrooms have their TRV's on 'frost', which means they came on this morning but then turned themselves off after about 30 minutes. The box room TRV is 1.5 and the bathroom is 6. Downstairs the living room radiator is fully open, hall on 3, kitchen on 3 and conservatory on 'frost'.
Just to give you an idea of the area I'm trying to heat, and when, I've been round with the measuring tape today and have worked out that the total radiator area for the whole house is 5.26 sq m. First thing in the morning all these radiators initially heat up. When the radiators with low TRV's shut off, the total radiator area remaining is 3.14sq m.
I'm sorry this is such a long posting but I was so encouraged by today's progress that I thought it was worth giving you all the information that I had to see if anyone has any more ideas. Thanks for reading this for me.
That was a typo and you meant S53.
Unfortunately you are confusing the issue because when the boiler restarts many of the TRVs have closed thus reducing the flow rate through the heating system.
Any comparisoms have to be made at the same temperature conditions, e.g. starting from cold for example!
It may well be that your tests were comparing a d0=12 at a cold start with a d0=10 at a warm start!
In any case your preliminary tests seem to show that a d0=10-12 may be the optimum setting power but I would suggest further carefully controlled tests will be necessary.
The lower you can set d0 the more efficient the boiler is likely to be.
The pump over run could be set a little longer say d1 = 8 min rather than the factory setting of 5 min.
This has been edited to correct typos and add some more suggestions.
Tony
Thanks for your replies Dave and Tony.
Oops, sorry about my typo error. Yes I did mean S.53.
I also take your point about the fact that I'm not comparing like with like, that is, you're quite correct when you say that I tried d0=12 at a cold start and d0=10 at a warm start. But I'm learning! (bye the way, that d1 on your responses rather than d0 was a typo I hope?!).
This morning the central heating started beautifully at d0=12, with a steady increase in temperature which reached 68C in 20 minutes. However, there was that 10 minute S.53 delay when the boiler later tried to restart from warm.
I'm now going to turn everything off, let it get cold and try reducing d0 down to 8 and will report back.
Thanks again.
Mary Jane.
Oops, sorry about my typo error. Yes I did mean S.53.
I also take your point about the fact that I'm not comparing like with like, that is, you're quite correct when you say that I tried d0=12 at a cold start and d0=10 at a warm start. But I'm learning! (bye the way, that d1 on your responses rather than d0 was a typo I hope?!).
This morning the central heating started beautifully at d0=12, with a steady increase in temperature which reached 68C in 20 minutes. However, there was that 10 minute S.53 delay when the boiler later tried to restart from warm.
I'm now going to turn everything off, let it get cold and try reducing d0 down to 8 and will report back.
Thanks again.
Mary Jane.
I have not followed the whole discussion but has the pump speed under d19 been set to "3" i.e. max on CH ?
If so then there may be an advantage in adjusting the bypass screw to the left of the pump!
I would suggest you unscrew it ONE turn at a time ANTICLOCKWISE and carefully monitor the incidence of S53 indications on consistent WARM restarts.
Note on paper each time you turn it and the direction so that you can keep track of the position and return it to the starting position if required.
It is a multiturn screw and the effect of a single turn is small.
Tony Glazier
If so then there may be an advantage in adjusting the bypass screw to the left of the pump!
I would suggest you unscrew it ONE turn at a time ANTICLOCKWISE and carefully monitor the incidence of S53 indications on consistent WARM restarts.
Note on paper each time you turn it and the direction so that you can keep track of the position and return it to the starting position if required.
It is a multiturn screw and the effect of a single turn is small.
Tony Glazier
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