Anyone any knowledge of HeatMiser UH8?

Phibsboro

Hi,

I am an end user who is trying to understand what my plumber is doing so I can talk the same language to him as I attempt to ensure a newly installed system is adaptable to home automation.

The system is a 3 zone underfloor heating downstairs and a 4 rad zone upstairs with a Baxi combi bolier (so no hot water control issues).

The plumber is going to install a heatmiser control system, specifically a UH8, with wired stats to the 3 zones downstairs. For the boiler he is talking about a timer control or a hive for overall control.

I am trying to ensure I will (or can in the future) have control over the heating system via an app - I am not too fussy on what system I use as I intend to bring it all into an open source home automation called Home Assistant.

Could someone offer an explanation of what the UH8 is capable of, in terms of ordinary, non-smart, control? He was initially saying that the 3 UFH thermos couldn't call for heat, all they did was turn off the UHF value for that zone (and therefore the boiler timer was crucial), though he backed off that slightly after reviewing the box of the UH8. Some basic quesitons:

1. From my reading of the UH8 manual, it does have a volt free switch for the boiler. Is that correct?

2. Assuming it can switch the boiler, is it able to call for heat based on at least one of the 3 zones being open?

3. How might the upstairs rad zone work? He is talking about putting manual TRVs upstairs so I get the impression he is talking about running the heating to them based purely on the boiler clock. The UH8 manual talks about having one rad zone but I'm not clear what exactly that is offering in terms of control. If the UH8 can in fact switch the boiler, does a boiler clock even make sense?

In terms of home automation, I am looking at a simple replacement of the heatmiser stats with smart stats like the Tado ones - I've created a question in the IoT forum about that.

Any info to help me understand what the UH8 is capable of would be really appreciated.

Thanks.

wasim21k

Hi,
very recently i had opportunity to help friend of mine to replace heatmiser controller with opensource controller while using heatmiser (UH1) board to control zone valve, this place had 8 manifold with different number of zone on each manifold.

These boards including UH8 are just very basic relay boards and does not have any intelligence on boards (any micro controller etc). Room thermostat call for heat by triggering relay for zone and then board have relay connection for UFH pump and UFH Valve. UH8 manual does say boiler (in out is volte free) which mean it has ability to trigger boiler.

Depending on your controller/room thermostat single or multiple zone can call for heating at any time. i m not sure why your installer is trying to put manual TRV for upstairs, do you not have same zone electric valve for upstairs manifold? do you have upstairs rooms as one zone without any electric valve?

sorry can not speak for tado or any other commercial solution as i never used one.
quick google for UH8 brought me this installation manual

Phibsboro

wasim21k wrote: »

Hi,
very recently i had opportunity to help friend of mine to replace heatmiser controller with opensource controller while using heatmiser (UH1) board to control zone valve, this place had 8 manifold with different number of zone on each manifold.

These boards including UH8 are just very basic relay boards and does not have any intelligence on boards (any micro controller etc). Room thermostat call for heat by triggering relay for zone and then board have relay connection for UFH pump and UFH Valve. UH8 manual does say boiler (in out is volte free) which mean it has ability to trigger boiler.

Depending on your controller/room thermostat single or multiple zone can call for heating at any time. i m not sure why your installer is trying to put manual TRV for upstairs, do you not have same zone electric valve for upstairs manifold? do you have upstairs rooms as one zone without any electric valve?

sorry can not speak for tado or any other commercial solution as i never used one.
quick google for UH8 brought me this installation manual

It looks like upstairs is single zone with no rad zone valve, I get the impression plumber is thinking of putting an overall timer on the boiler to deal with upstairs, which means that it will be heating all day as far as I can see (I work from home, so the downstairs will be on for most of the day). If there is a rad valve then I'd rather he put a wired stat in the main bedroom and ran that into the optional rad zone 8 which could then call for heat and switch the rad valve. That wired stat could then be placed by a tado, meaning I wouldn't need to go near the boiler at all in terms of tado.

If he can't get a wired stat upstairs (which is possible as we are plastering at this stage) then I might put a tado extenstion kit into that zone 8 input and run a wireless tado stat into that extension. Though I think that will totally confuse him!

wasim21k

First thing first, if i had choice to install zone valve then I would definitely Do it, in long run it will save you on your heating bill.

controlling 8th zone should be easy enough but best to run cable from main manifold to 8th zone (upstairs) if possible, this way you wouldn’t be limited to controller choices, Ask your installer to draw all on paper beforehand once you see all on paper it will make more sense and easy to understand.