It happens if bypass is open or closed
This is how the boiler has been functioning for a number of years
Optimising Vaillant Ecotec plus 637 always cycling
- Thread starter Fireitup
- Start date
This is how the boiler has been functioning for a number of years
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Can you watch d.41 next time you request CH and see if its rising. The boiler fired for ~ 19secs then stayed off for ~ 42secs before coming to life again, don't know if this is some form of micro firing because if the boiler had gone into recycle then it should have stayed off for at least 2 minutes with a target temp of 65C even if the recycle time was set to 1 minute, if its set to its default setting of 20 minutes then it should have stayed off for 4.5 minutes, can you check d.01 & d.02.
If you request CH&HW together, or HW only, does it fire up then?
Next time you get it to run continuously on CH only, can you note the flow/return temps, d.40&d.41.
Your second video, just shows a steady 48C for 9 seconds, does it stay firing at 48C with a target temp of 65C?.
Happy Christmas.
John.
If you request CH&HW together, or HW only, does it fire up then?
Next time you get it to run continuously on CH only, can you note the flow/return temps, d.40&d.41.
Your second video, just shows a steady 48C for 9 seconds, does it stay firing at 48C with a target temp of 65C?.
Happy Christmas.
John.
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D41 does not rise
D1 is 5
D2 is 20
What do you mean it fires up with CH and HW and HW on its own?
Thats correct it will stay firing at a temp in the 40s
D1 is 5
D2 is 20
What do you mean it fires up with CH and HW and HW on its own?
Thats correct it will stay firing at a temp in the 40s
Looks like no circulation, maybe pump not actually starting.
I mean by CH & HW on is does it fire up with CH&HW both requested on together and by HW on its own I mean does it fire up if HW only requested on.
Noting D40&D41 next time it's running on CH only will tell a lot.
It will only stay firing at ~ 48C if you have set d.00 too low and the heat demand is more than the now restricted boiler output.
I mean by CH & HW on is does it fire up with CH&HW both requested on together and by HW on its own I mean does it fire up if HW only requested on.
Noting D40&D41 next time it's running on CH only will tell a lot.
It will only stay firing at ~ 48C if you have set d.00 too low and the heat demand is more than the now restricted boiler output.
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The d40 is the set temp say 60 or 65
The d41 is 32 or 36
The pump is working otherwise there would be no heat?
D00 is 22kw, if I set it above 24/26 then it makes noises and as suggested on another thread, the d00 is too high hence the noises
No. d40 is the actual flow temperature, if this is what you are getting then a dT of 28/29C is far too high and close to the burner trip point and recycle, the burner then will find it very difficult to refire successfully
But once it's reached temp, the d40 screen then keeps dropping...
What's the solution?
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