Question about opentherm

[Husk24]

hi guys

Im thinking of buying a nest thermostat. I am aware my boiler is opentherm compatible. Im particularly interested in the way the boiler runs using opentherm. After installing this thermostat I decide do not like the way opentherm works, would it be easy as switching opentherm off from the nest settings or will it be wired in a way I would have to get it re-wired/changed?

 

[Harvest Fields]

The second one mate

 

[Husk24]

Damn

 

[Husk24]

Is is more efficient cheaper to run it via opentherm?

 

[Harvest Fields]

Is is more efficient cheaper to run it via opentherm?

Depends on your house and how warm you like it. (It is more complicated than that, but very long winded)

 

[gingalig]

Is is more efficient cheaper to run it via opentherm?

It's designed to interlink as an open therm device. It baffles me as to why anyone would want to do anything different. You will have a huge scope of settings to tailor the outputs and timings to pretty much any of your requirements.

 

[Husk24]

I guess the option to use ‘true radiant settings’ on the nest would be just as good.

 

[Husk24]

@gingalig

So you would definitely recommend opentherm?

 

[Harvest Fields]

@gingalig

So you would definitely recommend opentherm?

No I would recommend ebus. But your boiler probably doesn’t support it if it has opentherm.

 

[gingalig]

@gingalig

So you would definitely recommend opentherm?

Your installer will look very confused if you try and suggest anything different, and would probably charge considerably more if they agreed to do it. If you really want more control or savings maybe consider evo home or drayton wiser. Nests are good though and very user friendly.

 

[Knappers]

If you have an opentherm compatible boiler and wiring so you can connect nest with opentherm (bus) then do it - no brainer.
Worry about the technical side later but you will have greater control over the boiler and the option not to use the advanced features, not using opentherm downgrades the nest to a very nice and fancy on and off switch.

 

[Husk24]

I have a ideal logic system 30 boiler, a month old, can someone confirm it will definitely be opentherm compatible with all the connections or what ever is required

 

[gingalig]

I have a ideal logic system 30 boiler, a month old, can someone confirm it will definitely be opentherm compatible with all the connections or what ever is required

If you use a nest installer or alternatively a GSR then they will make all the necessary wiring connections and bring any other equipment required.

 

[garygvl]

I have a ideal logic system 30 boiler, a month old, can someone confirm it will definitely be opentherm compatible with all the connections or what ever is required

sorted out your heating problem then

 

[Husk24]

I have a new boiler now, but the thermostat given has issues as per my other thread, doesn’t work all the time, I have even started thinking if it interferes with my cars sensor as they both run on the same frequency! It seems to work ok when my car is not at home (when im away) lol

 

[Husk24]

I called a nest installer today and apparently I can’t have opentherm, my current set up as follows, ideal logic boiler 30k, new boiler recently installed, i have two timers, one comtrols water and downstairs heating and other timer controls upstairs but I can’t have upstairs on independently, downstairs has to be on for upstairs to fire up (strange setup from previous owner who was a builder), so based on this info can I have opentherm?

 

[Knappers]

Sounds a bit unusual, I guess downstairs is the main control and upstairs runs a zone valve to control heating.
However if main downstairs stat/nest is satisfied or running at low temp and upstairs calls for heat then you'll be left wanting for more heat upstairs, if you fit full controls upstairs then without a zone valve for downstairs it would also run downstairs.
Drayton wiser is I think one of the most cost effective solutions for smart control of multiple zones and I think it's opentherm compatible altho its a bit simpler than nest and I know nothing about it's heating curves.
If the system is as I've described then you would also need a second d zone valve for downstairs and a decent bypass before it, so it's starting to get complicated.
As said before your probably looking at that or an evohome system.

At this point even for myself I'd be considering just using the I/0 terminals for normal control, your only really dropping load compensation and altho I think it's a great feature you'd probably never notice the difference.

 

[dan_the_plumber]

Which Nest unit have you got? Which boiler have you got? Thanks