Vaillant ecoTech plus setup

[AndrewOllason]

Hi,

I am new to forum so apologies if this question has been covered. I have searched the net and this forum and just seem to get more and more confused!

I have what I think must be a very common system. 18kW boiler feeding Y plan mid position valve, radiators with TRV's and vented cylinder. There are a few non TRV radiators and no bypass valve. Controls are non Vaillant and consist of a two channel time clock and mechanical room thermometer. Cylinder has standard type clamp on stat.

I would like to operate the system as follows.

CH - 5/2 timed control with flow temperature set by me depending on weather (happy to use existing control on boiler)
DHW - 5/2 timed control with flow temperature set at 82 degrees celsius.

Question is - if I upgrade to VR65/timeswitch 140/VRT30 will I get this level of control?

What happens in the mid position when Ch and DHW are calling? Do I need to revert to a non mid either DHW or CH situation to have two different flow temperatures for the two circuits.

Seems simple in theory but I am having problems getting a straight answer!

Thanks for reading

 

[bell824]

straight answer is no no no and no to all ov the above.

you would need a vr65, vrc 392 or new 470 weather compensator (me thinks thats the new one) and a vr 10 fixed to the side of the cylinder (ad hoc hash bash job, better with unvented cylinder for this control setup), this would then allow you to use a 3 port or 2, 2 ports, the vr65 would concentrate the selected flow temp (aforementioned set point of cylinder (not flow temperature)) from the hot water control knob hen once the cylinder is sattisfied (hence unvented is better) allow the heating to work.

long winded but that is basicaly your answer.

 

[Hufty]

Just to add to what bell824 has put: a VR10 comes in the box with the VR65. If you use the VR10 then DHW takes priority over CH whatever valves you use. If however you use a normal cylinder stat with a midpos valve then there is a setting in the boiler to have it running as a mid pos, but you lose the supposed efficiencies provided by the VR10.

You might be better off simply putting TRVs on all radiators, sticking with your timeclock (or getting a new one) , and maybe getting a TPI room stat such as a DT90E.

The VRT30/140 combination doesn't really make sense when there are better options available even from Vaillant, and you have to shell out for a VR65 to make it all happen. I would look again at the 392 or a 430f (not a fan of the 470 myself)

 

[gas4you]

If you use the VR10 then DHW takes priority over CH whatever valves you use.

You have a choice in the boiler settings whether you want it to be HW priority or not.

 

[Onetap]

straight answer is no no no and no to all ov the above.

Hang on there. I have the VR65 & VRC430 and it does most of that, with a few minor differences that I'll detail when I get time; or else i've misunderstood something here.

..................... and a vr 10 fixed to the side of the cylinder (ad hoc hash bash job, better with unvented cylinder for this control setup).

Again, hold up, I have exactly that, VR 10 stuck to side of a standard vented cylinder. It works fine, haven't even looked at it since I installed it. If care is taken in removing a fag-packet sized bit of insulation and fitting the sensor, it is unobtrusive to the point of being almost invisible (except for the cable poking out). Vaillant don't give detailed instructions because they want to flog their Unistor unvented cylinders (with VR10 fitted) to the gullible. It has exactly nothing to do with vented/unvented cylinders.

 

[Hufty]

If you use the VR10 then DHW takes priority over CH whatever valves you use.

You have a choice in the boiler settings whether you want it to be HW priority or not.

Yeah mate as per my previous post on this topic, that setting doesn't work if you use the VR10 only if you use a cylinder stat. You'll have to try it rather than just read about it.

I do however agree with onetap, the VR10 works fine with any cylinder - aluminium tape if it's one with a jacket rather than spray on insulation. IMO Vaillant don't like it because they can't control exactly where on the cylinder the sensor ends up so when it says 60degC it might not be 60degC, but customers quickly find what works for their setup.

 

[gas4you]

I don't read about it. I do it

 

[Agile]

Hi,

DHW - 5/2 timed control with flow temperature set at 82 degrees celsius.

Thanks for reading

Why would you want the boiler set at 82 C just to heat your cylinder?

When a lower setting will also heat it but much more efficiently even if it takes a few minutes longer!

Tony