Hi I'm new here, hope this isn't too rambling and someone can help...
I had a Vaillant Ecotec plus 630 installed into my mid terraced, OK insulated house with 11 radiators around 18 months ago. It's generally performed fine, making big savings on the non-condensing boiler that it replaced but I've got a few questions.
Is there a way to tell when the thing is condensing?
Wondered if there was an installer parameter code that might indicate whether it is or not...
Balancing the rads
I noticed that some rads weren't getting as hot as others so decided to balance the system using an infrared thermometer. Looking through the boiler manual, I found that code d40 displays flow temperature and d41, return temperature. Excellent, I thought - this should make things easier. I then balanced all the rads no probs but the readings the boiler display gave didn't make sense - a return temp of 59c with flow temp at 65c = 6c drop! I decided to measure the flow and return pipe temperatures just before the boiler and they showed more what I expected: 63c flow and 45c return, a drop in line with what I'd achieved over the rads and also a return temp that (I hope) will allow the boiler to condense.
So is the reading of d41 faulty or am I misunderstanding what it's actually displaying?
Thermostat behaviour
The single zone CH is operated by a Honeywell DT90E Thermostat and Honeywell ST9400C controller. According to the Thermostat manual, you can set the number of 'calls' per hour the thermostat makes to the boiler to achieve the desired temperature. At the moment it's set to 6 per hour ( default). When the desired temperature is reached, the demand goes off and the boiler goes into lockout (anything between 2 and 4 mins) with the pump on overrun (set to 5 mins). Once the lockout time has passed, and if there is demand, the boiler kicks in again but seems to burn very low around 48c for a few minutes before finally firing up to full blast and 65c target flow temperature, for a couple of minutes max. Then another 10 min 'call' is up so the whole process starts again.
I've read in a few places that the fewer calls to the boiler the better, so would setting it to 3 per hour make sense?
Should I look at adjusting the boiler pump overrun or lockout times at all? I wondered if making these longer would allow the system to just pump the already heated water around, operate in what I think is condensing mode for longer and maybe miss the full firing cycle towards the end of the 10 minute call window?
I've read that Vaillant make room thermostats (VRT50) that are continuous and modulate the burner. Would one of these cut out all the boiler lock out/firing up activity? I think they only run via the Vaillant ebus system so would have to buy a new timer and VR66 to make all that work which seems quite an outlay...
Heating Partial Load setting
Parameter d0 is currently set to 30kW. I have 11 rads plus a hot water tank, so does this setting really need to be so high? What would be a good figure to change it to, or does the 'auto' setting do a pretty good job of getting it right?
Thanks in advance to anyone who can take the time to help answer theses. I've spent a good few weeks trawling the web but not been able to find answers and the installer pretty much setup it up and left without really explaining (or balancing) the system very well.
I had a Vaillant Ecotec plus 630 installed into my mid terraced, OK insulated house with 11 radiators around 18 months ago. It's generally performed fine, making big savings on the non-condensing boiler that it replaced but I've got a few questions.
Is there a way to tell when the thing is condensing?
Wondered if there was an installer parameter code that might indicate whether it is or not...
Balancing the rads
I noticed that some rads weren't getting as hot as others so decided to balance the system using an infrared thermometer. Looking through the boiler manual, I found that code d40 displays flow temperature and d41, return temperature. Excellent, I thought - this should make things easier. I then balanced all the rads no probs but the readings the boiler display gave didn't make sense - a return temp of 59c with flow temp at 65c = 6c drop! I decided to measure the flow and return pipe temperatures just before the boiler and they showed more what I expected: 63c flow and 45c return, a drop in line with what I'd achieved over the rads and also a return temp that (I hope) will allow the boiler to condense.
So is the reading of d41 faulty or am I misunderstanding what it's actually displaying?
Thermostat behaviour
The single zone CH is operated by a Honeywell DT90E Thermostat and Honeywell ST9400C controller. According to the Thermostat manual, you can set the number of 'calls' per hour the thermostat makes to the boiler to achieve the desired temperature. At the moment it's set to 6 per hour ( default). When the desired temperature is reached, the demand goes off and the boiler goes into lockout (anything between 2 and 4 mins) with the pump on overrun (set to 5 mins). Once the lockout time has passed, and if there is demand, the boiler kicks in again but seems to burn very low around 48c for a few minutes before finally firing up to full blast and 65c target flow temperature, for a couple of minutes max. Then another 10 min 'call' is up so the whole process starts again.
I've read in a few places that the fewer calls to the boiler the better, so would setting it to 3 per hour make sense?
Should I look at adjusting the boiler pump overrun or lockout times at all? I wondered if making these longer would allow the system to just pump the already heated water around, operate in what I think is condensing mode for longer and maybe miss the full firing cycle towards the end of the 10 minute call window?
I've read that Vaillant make room thermostats (VRT50) that are continuous and modulate the burner. Would one of these cut out all the boiler lock out/firing up activity? I think they only run via the Vaillant ebus system so would have to buy a new timer and VR66 to make all that work which seems quite an outlay...
Heating Partial Load setting
Parameter d0 is currently set to 30kW. I have 11 rads plus a hot water tank, so does this setting really need to be so high? What would be a good figure to change it to, or does the 'auto' setting do a pretty good job of getting it right?
Thanks in advance to anyone who can take the time to help answer theses. I've spent a good few weeks trawling the web but not been able to find answers and the installer pretty much setup it up and left without really explaining (or balancing) the system very well.