Author Topic: Nest/Hive/other IP enabled thermostat  (Read 4049 times)

Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #50 on: November 20, 2017, 12:03:43 pm »
The TRVs should be used appropriately, leaving them on full tilt defeats the object of having them if thermal comfort is not happening. Given that you have a recent boiler you may wish to talk to your heating engineer  about installing an external compensator, which will moderate the heating relative to prevailing external conditions and should also save on heating bills, whilst extending the life of the boiler. The installation of compensators when having boilers replaced will probably become compulsory in the not too distant future.
'Absence of evidence is not evidence of absence'.

Martin John Rees.

Aunt Maud

  • Le Flâneur.
Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #51 on: November 20, 2017, 05:07:06 pm »
If your insulation is not up to much, then an external doodad connected to the boiler is useless.

You could replace the TRV's with a manual affair for a fraction of the cost of calling a heating operative

'Absence of evidence is not evidence of absence'.

Martin John Rees.

Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #53 on: November 20, 2017, 10:16:23 pm »
The building is moderately well insulted but the usage is intermittent as we are not staffed everyday and the house is empty overnight.  The office is a semidetached house with upgraded loft insultaion  and double glazing. 


Aunt Maud

  • Le Flâneur.
Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #54 on: November 21, 2017, 08:51:41 am »
Whilst playing at being a plumber, I came across a Danfoss article which said that the TRV and the lock shield valve should be placed on the same side of the radiator, with the TRV on the top outlet.

I'll try and find it again.

Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #55 on: November 21, 2017, 09:31:47 am »

our problem is that the thermostatic valves on the radiators are stiff to turn and tend to be left open so that we end up with an office that is roasting hot.  We have 4 radiators in total down stairs.

I could replace the valves heads but the valve for the largest radiator is stuck behind a desk and is clearly very inefficient.

I have looked at having a NEST fitted but not sure whether it would be worthwhile.  I presume that if the NEST thermostat controls everything then I do not need thermostatic valves.  Is that correct?  The floor area is low enough that one thermostat could very well control everything I think.

I think you might have your own answer:
1. If you have a room thermostat already on the ground floor and you think this would adequately control the offices, then leave the TRVs wide open and let the thermostat control the space heat.  You shouldn't have TRVs and room 'stats fighting each other to control the space heating.

2. If you don't have a room 'stat (and the boiler is using return temperature to control output), then replace the TRVs and set them according to the temperature requirements of each room.  I'd be inclined to do a proper job and replace the body of the valve as well as the TRV "top".  It's probably the body of the valve that's stiff not just the top.  This will then give you reliable control if you use decent TRVs (I've used Drayton TRV4s in several houses with no problems, but cheapy ones have had a few problems over the years).  Yes, this might mean moving a desk and a bit of temporary pain and expense but it's better long term than roasting the place and modulating the heat by opening windows in the dead of winter.  If you're a gadget fiend then some sort of electronic TRV might allow individual room times/temperature etc but they are pricey and introduce additional maintenance issues (battery replacement at least every 5 years).  In a commercial setting, you might look for TRVs that can be locked to a fixed temperature to prevent staff tinkerage.

Use the boiler timer controls to switch off or set-back the heating to a lower temperature overnight/weekends when the office is unoccupied.

I don't have any direct experience of Nest, Hive etc, but they sound like overkill for a small office.  If you have timer control on the boiler and local control for space temperature then smart thermostats are a bit of an expense unless you're really going to use your phone/tablet to tinker with the heating remotely.

Kim

  • An appetite for the epic, but no real stamina
Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #56 on: November 21, 2017, 12:50:51 pm »
The main things a smart thermostat gains you over traditional controls are occupancy detection and remote control.  How beneficial those are going to be will depend on how well the use of the space can be predicted by a simple timer...
I do find anything involving ball bearings oddly satisfying

Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #57 on: November 21, 2017, 09:06:48 pm »
Thank you

Food for thought.  The desire for fun may outweigh the cost of installation of a NEST so that i can see how it works.  I am fortunate to own the building and have control of such things.

Aunt Maud

  • Le Flâneur.
Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #58 on: November 21, 2017, 10:05:02 pm »
Do these things just measure the temperature in one room only ?

Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #59 on: November 22, 2017, 07:50:07 am »
The original NEST apparently did. Now you can get one NEST per zone valve but then the costs really mount up.
The office is essentially open plan downstairs so it would work there with just the one.

The boiler does not have multi day programming so I probably would benefit from something that added multi day although we do go in some weekends so the ability to warm the office remotely as I walk round would be good.

Aunt Maud

  • Le Flâneur.
Re: Is NEST worthwhile and does it replace thermostatic radiator valves
« Reply #60 on: November 22, 2017, 09:00:27 am »
It all seems to be a compromise with domestic heating controls. My ideal system would be a thermostat on the wall in each room, with each radiator working independently on a valve controlled manifold circuit.

That would require wires, sensors, valves galore and a shed load of work.

Re: Nest/Hive/other IP enabled thermostat
« Reply #61 on: November 22, 2017, 10:15:27 am »
Thread resurrection.

It's Black Friday time again, so I can get Hive or Nest for about £160 installed. Our thermostat has a broken LCD, so I can't set the temperature to a number any more (standard Honeywell issue but out of warranty) so it's an ideal opportunity for a new useful toy. While I love the idea of the Evohome with every room configurable, it's too expensive and complicated and I'm not up for plumbing.

What are the current recommendations,and how are people getting on with their device chosen last year?