** I have seen odd posts in other places that say having lots of FHT senders (room programmers) causes problems due to radio packet collisions.
This I understand - the protocol is simplex, retried 3 times per message IIRC, so has no way to know if collisions drowned out some messages.
So - in practise - has anyone used an FHT system with upto 10 zones in a single 2 storey house?
Cheers!
Tim
More details;
I like the simplicity of the FHT system.
I also like the fact that the room programmer/stat is separate to the radiator motor unit - one big failing of TRVs is that they have a big hot lump of metal right next to them!
I also like the fact the the FHT has a boiler control relay that works out of the box (OK, pairing, but not much effort).
I like the fact that I can fall back to a simple boiler timer and adding TRV heads if it all goes horribly wrong (though this is true of several systems)
I did also like the look of the HomeMatic with the CCU2 programmer, but it's not as simple and the room programmer is in the rad motor unit which is a PITA to get at in some cases, plus the point above regarding sensing temperatures.
Mine would be set up:
7-8 FHT80b room controllers
paired with:
10 FHT 8V rad motors
1 FHT 8W (boiler call-for-heat)
PLUS
2 FHT80b room controllers
paired with:
2 FHT 8V rad motors
1 FHT 8W
The latter is for 2 rooms with underfloor heating - needs a separate pump and mixer valve - will use a relay to cause this to also call-for-heat from the boiler.
This I understand - the protocol is simplex, retried 3 times per message IIRC, so has no way to know if collisions drowned out some messages.
So - in practise - has anyone used an FHT system with upto 10 zones in a single 2 storey house?
Cheers!
Tim
More details;
I like the simplicity of the FHT system.
I also like the fact that the room programmer/stat is separate to the radiator motor unit - one big failing of TRVs is that they have a big hot lump of metal right next to them!
I also like the fact the the FHT has a boiler control relay that works out of the box (OK, pairing, but not much effort).
I like the fact that I can fall back to a simple boiler timer and adding TRV heads if it all goes horribly wrong (though this is true of several systems)
I did also like the look of the HomeMatic with the CCU2 programmer, but it's not as simple and the room programmer is in the rad motor unit which is a PITA to get at in some cases, plus the point above regarding sensing temperatures.
Mine would be set up:
7-8 FHT80b room controllers
paired with:
10 FHT 8V rad motors
1 FHT 8W (boiler call-for-heat)
PLUS
2 FHT80b room controllers
paired with:
2 FHT 8V rad motors
1 FHT 8W
The latter is for 2 rooms with underfloor heating - needs a separate pump and mixer valve - will use a relay to cause this to also call-for-heat from the boiler.
Comment