[flyingearly]

I've just about had it up to my eyeballs with Hive, but posting here to give it one last try...

We have a Hive heating system and smart TRV on all the radiators connected to the app. We have a towel rail, but this doesn't have a TRV on it.

Obviously, being a British summer, the temperature has just crept into double digits and as a consequence we don't have our heating on at the moment.

What we want to do is have a small blast of heating mid-morning purely to get the towel-rail warm enough to dry the towels that hang on it from the morning wash (assuming we can't hang them outside, because it's raining).

I had thought that the obvious way to do this was to switch all the radiators to 'OFF' (which sets them at 7 degrees in the app) but set the main heating to 25 degrees for 30 minutes (e.g. above ambient summer temperature); my assumption was that as a consequence the towel rail - being the only element without the TRV - would heat and the rest wouldn't.

What actually happens is that all the radiators seem to heat up, which is very wasteful and not needed.

Any ideas? I was wondering whether the TRVs need to be set to 'manual' at 7 degrees, rather than 'off' (e.g. does 'off' actually mean 'turn off the smart element of the TRV' rather than 'don't heat')?

[Flyin'Dutch']

That's an expensive way to get some dry towels!

[PeteSpencer]

Our system not hive but similar has underfloor (water piped)heating with a programmable Heatmiser wall thermostat in each room which feeds back to a central valve manifold .

Upstairs bedrooms have radiators with TRVs and bathroom ensuites have ‘ladder’ style towel rail radiators.(As well as Heatmiser programmable thermostats in every upstairs room.)

Each towel rail/radiator however has a small programmable electric heater element which when the house heating is off in the summer can be set with a small number of options: on, on for a couple of hours twice a day or a single two hour blast .

The heating elements can also be retro-fitted I understand.

We can also sort of fool the system in a similar way to you by turning off the bedroom radiator TRVs but turning the bedroom room Heatmisers up high (28+deg).

This mysteriously sometimes works but sometimes doesn’t .Our plumber says it’s not a good idea though as it ‘puts a strain on the system’, so we use the ‘lectric…..

I should add that for some mysterious reason all bathroom/ensuite towel rails (we have two bedrooms downstairs and two upstairs) are in the same water heating circuit as the upstairs bedroom radiators.
The heating circuit plans of our underfloor heating look like a nightmare schematic map of the London Underground.

[stevelup]

Can't you zone the system, and then turn on the rad in only one room (which will, by definition) heat the towel radiator. I don't know if Hive is zoneable.

If it is, I'd say you need a smart TRV on at least one towel radiator. You can then turn on just that one zone.

We've got Honeywell EvoHome here, and both the towel radiators have TRVs on. In summer, they come on at 35C for just five minutes at 7AM and again at 7PM - that's more than enough.

The reason for 35C was to make sure they heated no matter what... and 5 mins is more than enough.

[flyingearly]

Mmm, interesting - that is what I was trying to do; all the TRVs are set to off, but the main system gets set to 25 degrees for 5 minutes; but the individual TRVs are still heating. With Hive, there is a main thermostat in the lounge separate to the TRVs so that is what I was setting to the higher temperature.

My understanding was that this thermostat effectively sets the temperature for the overall system, but the individual TRVs limit each zone to 7 degrees (or off), but clearly my understanding is wrong!

[rikur_]

Given the inefficiency of boilers at low load, and of heating water in the pipes leading to the towel rail, I'd be surprised if a simple electric heater in the towel rail isn't cheaper to run.

The way you are attempting it sounds like it should work based on my understanding of Hive.
One thing to be aware of, is that after new batteries are installed, or a reset, the TRVs have a learning period where they slowly open and close to learn over ~ 2 hours of the system operating. Is it possible that your TRVs are still in the learning phase?

[CloudHound]

I too am sick of Hive.

Still having problems.

[riverrock]

There are a fair number of complaints on their website about the TRVs - generally on them allowing the temperature in a room to become too hot. There is apparently a firmware update available that they are currently testing on a small number of complainers.
Note that it can take up to 40min for a Hive TRV to move to closed.

I haven't gone for smart TRVs so I've no personal experience. The thermostat / app / lights work fine for me.

[stevelup]

That's why I went Honeywell... a company that's been making heating controls since the beginning of time -vs- a dot com startup!

[riverrock]

@stevelup - Hive was created by Centrica, better known as British Gas. It really isn't a dot com startup! Even if they seem to have that attitude at times (which can be refreshing in a large corporate institution).

[Flyin'Dutch']

@riverrock I admire your positivity when it comes to British Gas, in my experience, and that of countless others, they are pretty sh*t*

[JonathanB]

If smart TRVs weren't so bloomin' expensive I'd have liked to have gone that way. At the moment we have a Nest and apart from remotely being able to adjust, we're not overly using the smart functions as it just gets confused with my shifts!

I have 12 rads and 2 towel rails. The rads in the hallway and on the landing don't have TRVs as they are supposed to be the ones the themostat (in the hallway) directly controls I guess - mostly they're turned right down or off to get the rest of the house to actualy heat!

[rikur_]

Having made the switch from radiators, boiler, TRVs, actuator valves, zones, etc to air-source ceiling cassettes I'd never switch back. Each room individually controlled; only run it when you need it; heats or cools; and (in theory at least) maintenance free. Mitsubishi kit that's made for commercial use, and has 24 hour support (but does make the cost of a few TRVs look cheap )

[riverrock]

The traditional manual TRVs work fine, for me, so long as the thermostat is in the coldest (used) room in the house, so the rooms with TRVs get heat when required. For me, just as quick to turn a knob on a radiator as use an app!

[Flyin'Dutch']

Smart TRVs and associated systems are not there yet I think. I have some from Innogy and it is sort of OK but not grand.

More money could be saved and comfort raised by having a better insulated house and ground source heating and more solar panels and a bigger battery but even here, where energy is quite expensive (0.30€/kWh) there is not enough to be gained back by investing yet more) Suppose getting a heat pump equipped tumble drier would be good instead of the current one which is old squeaking and still has the hot air hose!) but somehow I can't chuck working stuff away to replace it 'just to save energy'

I know - bonkers.