Hi all.
I'm trying to optimise the working on my new boiler and control system, which is specced as follows:
Vaillant EcoTEC Plus 415 open vent boiler
Vaillant VRT360 room thermostat
Vaillant VR65 control center
which are interconnected using eBus.
Using existing Y-plan hot water 230v controls:
Cylinder thermostat
3-way valve
which are connected to the VR65.
It mostly seems to work well, and is so much quieter than the outgoing Potterton Suprima! But I'm having a few niggles in trying to optimise it, so a small collection questions...
The room stat is installed in the hallway, but it is a small 'room', just 1.5m x 1.5m, with the front door, stairs, and a radiator (no TRV).
1. I'm finding the current temperature reported by the room stat is a little slow to react to changes in the room temperature.
There is an adjustment on the stat called "Control characteristics/route adjustment" which is explained as "For optimum adaptation to the room size or radiator configuration. Default setting: 0. Adjustment range: -5 ... +5 (Positive values: room thermostat switches more slowly; negative values: room thermostat switches more quickly)"
Does this relate to the speed at which the current temperature is updated, or does it more mean the range around the set point temperature that the stat will switch at?
2. I am finding that the boiler gets itself into anti-cycling mode, quite easily. I've not had time to sit and monitor its exact behaviour yet, but I think it heats up quite happily for a while, including modulating itself down, then I assume the return flow gets a bit warm, so it turns off. After the pump overrun, it comes back on, but at full load, so turns off again before it has thought about modulating down. It then sits in anti-cycle mode for a while.
Is there an optimal way to set the flow/return, overrun/anti-cycle settings in order to minimise this? I believe it is going anti-cycle before the room is up to temp (though am not 100% on this yet).
3. It was my understanding that the hot water temperature control on the boiler, should only have any effect if I have a Vaillant UniStor connected using the sensor provided with the VR65. However, adjustment of this control during water heating, causes the boiler to switch out/in. Yet in water heating mode, the boiler appears to run the circulant at 80c regardless of anything else (whilst the cylinder stat is indicating a demand
for heat). What should I set the hot water temperature control on the boiler to?
4. I've read a couple of times on this forum that the radiator flow temperature control on the boiler should be set to maximum, and that the VRT360 will sort the rest out. Not sure I understand how the VRT360 is able to do this? What is the optimum setting for the radiator flow temperature on the boiler? I have it set to 65 and find the rads are really hot to the touch (but I'm a sensitive flower!).
5. What is the "Two-point/analogue operation" mode on the VRT360? I don't know what the difference is between these two modes?
Sorry it's quite long, I am trying to describe things as accurately as possible. Thanks for hanging in until the end, and in advance of any advice.
DH2
I'm trying to optimise the working on my new boiler and control system, which is specced as follows:
Vaillant EcoTEC Plus 415 open vent boiler
Vaillant VRT360 room thermostat
Vaillant VR65 control center
which are interconnected using eBus.
Using existing Y-plan hot water 230v controls:
Cylinder thermostat
3-way valve
which are connected to the VR65.
It mostly seems to work well, and is so much quieter than the outgoing Potterton Suprima! But I'm having a few niggles in trying to optimise it, so a small collection questions...
The room stat is installed in the hallway, but it is a small 'room', just 1.5m x 1.5m, with the front door, stairs, and a radiator (no TRV).
1. I'm finding the current temperature reported by the room stat is a little slow to react to changes in the room temperature.
There is an adjustment on the stat called "Control characteristics/route adjustment" which is explained as "For optimum adaptation to the room size or radiator configuration. Default setting: 0. Adjustment range: -5 ... +5 (Positive values: room thermostat switches more slowly; negative values: room thermostat switches more quickly)"
Does this relate to the speed at which the current temperature is updated, or does it more mean the range around the set point temperature that the stat will switch at?
2. I am finding that the boiler gets itself into anti-cycling mode, quite easily. I've not had time to sit and monitor its exact behaviour yet, but I think it heats up quite happily for a while, including modulating itself down, then I assume the return flow gets a bit warm, so it turns off. After the pump overrun, it comes back on, but at full load, so turns off again before it has thought about modulating down. It then sits in anti-cycle mode for a while.
Is there an optimal way to set the flow/return, overrun/anti-cycle settings in order to minimise this? I believe it is going anti-cycle before the room is up to temp (though am not 100% on this yet).
3. It was my understanding that the hot water temperature control on the boiler, should only have any effect if I have a Vaillant UniStor connected using the sensor provided with the VR65. However, adjustment of this control during water heating, causes the boiler to switch out/in. Yet in water heating mode, the boiler appears to run the circulant at 80c regardless of anything else (whilst the cylinder stat is indicating a demand
for heat). What should I set the hot water temperature control on the boiler to?
4. I've read a couple of times on this forum that the radiator flow temperature control on the boiler should be set to maximum, and that the VRT360 will sort the rest out. Not sure I understand how the VRT360 is able to do this? What is the optimum setting for the radiator flow temperature on the boiler? I have it set to 65 and find the rads are really hot to the touch (but I'm a sensitive flower!).
5. What is the "Two-point/analogue operation" mode on the VRT360? I don't know what the difference is between these two modes?
Sorry it's quite long, I am trying to describe things as accurately as possible. Thanks for hanging in until the end, and in advance of any advice.
DH2