Logic+ Combi 30 Hive Installation Sanity Check

[PowderblueKes]

Hey folks,

I've spent some time checking my setup and just wanted a quick sanity check before I take the plunge as there's a niggle that I can't resolve.

I have a Logic+ Combi 30 boiler with an "inbuilt" RF RFT1 mechanical 24hr timer and I'm looking to install the Hive Active Heating Single Channel.

Picture attached of my current setup (1).

Plan is to use a 5 core and set up the receiver/backplate as a new addition to the wall nearby as the current setup has only the isolator in the following attached setup (2). Plugging into the neutral, live and earth as standard and then using the left two sides for Terminals 1 and 3 on the Hive.

The niggle is... The instructions (on page 32) for the Logic+ Combi state that for a room thermostat to "Remove the link between the room stat/timer terminals" which has seen in (1) hasn't been done.

Should I leave the link or remove it for the installation of the Hive? My first instinct was to remove it. Then I was going to just pull the timer out the plug from the back (3) and slide out the timer at the front.

Any guidance or time taken to reply is much appreciated.

OOI - why is Terminal 2 on the Hive never used? I see many an instruction on just using 1 and 3 but never a justification and it piqued my interest.

Thanks

 

[muggles]

You shouldn't have the front cover off your boiler unless you're a Gas Safe Registered installer. It forms the safety room seal and should only be removed and refitted by someone capable of carrying out the Regulation 26.9 checks. The boiler should not now be operated again until those checks have been completed, and forum rules dictate that we can't advise you on any works within this casing.

I will say though that it's rather a shame to be putting an unintelligent control like Hive on a boiler capable of understanding commands from a much cleverer and more efficient OpenTherm-based controller.

 

[PowderblueKes]

Okay, cool.

 

[PowderblueKes]

Also, would you mind extolling the virtues of the preferred OpenTherm system you have in mind?

 

[DP]

Also, would you mind extolling the virtues of the preferred OpenTherm system you have in mind?

Instead of on/ off control that your proposed programmer executes resulting in ambient temperature swings about the desired temperature, OT will result in flat line because the programmer and boiler electronics are in ‘sync’ is perhaps easiest description

 

[muggles]

Also, would you mind extolling the virtues of the preferred OpenTherm system you have in mind?

Either Nest or Honeywell T6 are good. The great advantage of OpenTherm is that it requests the required flow temperature from the boiler to keep the room at a constant temperature, as opposed to a dumb on/off control which will always aim for the maximum. This is usually lower than the boiler's set temperature, and lower flow temperatures mean less gas burned. This is particularly true with condensing boilers, which only actually condense (and are therefore only properly efficient) when the water returning to them from the heating circuit is below 52°C. If the flow temp is lower, the return will be lower, and the boiler will be more efficient.

 

[PowderblueKes]

Much appreciated.

So, in a few weeks time when I get hold of a plumber to open up the boiler to do this and they are unsure what to do with the existing link inside the boiler. What should they do? Leave it or remove it?

 

[DP]

Much appreciated.

So, in a few weeks time when I get hold of a plumber to open up the boiler to do this and they are unsure what to do with the existing link inside the boiler. What should they do? Leave it or remove it?

In that case call in a heating engineer instead
While this is a broad statement not a yardstick, a plumber will be comfortable fitting a boiler but does not need to know how it does what it does, whereas a heating engineer will familiarise himself as to how the boiler works and how all the bits come together. There is a good chance the link you will need will not be there as it will have been binned when that clock was fitted to front of the boiler

 

[PowderblueKes]

Thanks DP.

 

[muggles]

Much appreciated.

So, in a few weeks time when I get hold of a plumber to open up the boiler to do this and they are unsure what to do with the existing link inside the boiler. What should they do?

They should learn how to do their job before inflicting themselves on the general public