Honeywell HOME EVO experts?

[virgilns]

After lots of faffing I'm looking seriously at the Honeywell homeevo system

I've got a Vaillant 637 boiler with VRC470 weather compensator

Unvented cylinder to be run as priority

I'd like towel rads (two bathrooms day 1, poss two more to follow in 5+ years) on their own zone so can be on on their own in the warmer months and the bathroom rad to top the heat up when required...

And between 7 and 11 more zones....

I've contemplated piping each zone seperately with 2 port valves, manifiods, LLH etc etc...

Home evo seems to give me half what I want...how would I combine Home Evo with unvented on priority? Honeywell and suppliers a re stumped...

 

[Dan Robinson]

It is a bit awkward due to G3 and manufacturers warranties.

But, you could, if you wanted to be very naughty, wire the CSA92 in series with the cylinders overheat thermostat and plumb the towel rails though the hot water primaries.


How this complies with the regs is any one's guess. Rumour has it that Honeywell are developing a kit to enable this.

If you want true hot water priority then you'll have to get jiggy with some relays, which could upset the Optimisation.

If you want more than 8 zones + hot water then you'll need a second Evo panel.

Do you REALLY need more than 8 heating zones?

 

[ALEC1]

the 470 with the vr 65 gives the hot water pririty..

evo home isn't compatible with the vrc 470, or any modulating controller, better to spend the money on insulation un less you have an Open therm bridge...then it won't communicate with the vaillant as thats ebus..


keep it simple...stick with valliant's own controls...or mix it with glow worms system pro for multiple zones...

 

[virgilns]

Hmmm, so what's the answer then? Got to be one!!

Am I back to your (Dan) recommendation of using manifolds and 3 4 way programmers...not the end of the world, but need to start the plumbing soon, so need to get a crack on with the planning.

is there such thing as a heating 'architect' as opposed to a heating installer...can't afford to sub the work out, but need o make sure I get it right!

 

[Dan Robinson]

There are plenty of us that will offer a design service. But it will cost you something.

The problem with your plans I suspect, is that you think you want more than you really need.

Plumbing probably isn't going to be your issue. Electrical knowledge and understanding of heating controls will be.

There are many ways to skin a cat, but first one needs to see said pussy.

 

[ALEC1]

evo home is really aimed at much bigger systems...apartment buildings in Germany for example, where the hydraulic set up accommodates variable flows caused by valves opening and closing. Such a system would have variable speed pump, and a low loss header.

On smaller systems technology has evolved to vary the flow temperature rather than the flow rate, this is the vaillant vrc 470.. such technology has a lower capital cost, lower install cost and is highly reliable, and highly efficient delivering a comfortable heating experience.

the design philosophy with compensation controls is to match heat loss to heat load as opposed to putting too much heat into a room to close a thermostatic valve...


the two different approaches can't be married sensibly... either you fix the flow temp so that opening valves can heat up quickly which means the flow temp is higher than necessary, or you float the flow temp for the whole system...with the 470

 

[virgilns]

evo home is really aimed at much bigger systems...apartment buildings in Germany for example, where the hydraulic set up accommodates variable flows caused by valves opening and closing. Such a system would have variable speed pump, and a low loss header.

On smaller systems technology has evolved to vary the flow temperature rather than the flow rate, this is the vaillant vrc 470.. such technology has a lower capital cost, lower install cost and is highly reliable, and highly efficient delivering a comfortable heating experience.

the design philosophy with compensation controls is to match heat loss to heat load as opposed to putting too much heat into a room to close a thermostatic valve...


the two different approaches can't be married sensibly... either you fix the flow temp so that opening valves can heat up quickly which means the flow temp is higher than necessary, or you float the flow temp for the whole system...with the 470

Thanks Alec.

The problem I se is that I want independant timing for each room. I guess I can live with less 'stats, but that still gives me 'old skool' control of one temp reference point for the whole house...

 

[virgilns]

Dan_R...just sent you a message on your profile page re design of system. let me know if you fancy the callenge