DanfossRandall TP5000SI RF + RX1 Programmer

This programmer and control unit was purchased to replace an existing similar Danfoss unit that, after more than 13 years of continuous fault-free operation was now showing signs of age. The tens of hours digit on the LCD was dim, and fading. Bear in mind that this represented more than 113,000 hours. The replacement was an easy exercise that took about 15 minutes. This new version, whilst essentially the same, does come with some internal firmware and hardware enhancements, notable amongst which was the fact that as soon as the batteries were inserted into the programmer it displayed the correct date and time. A little investigation showed that its Real-Time Clock was backed up by an internal lithium battery, and so it will maintain correct time even without the main batteries. In addition there are several new operating modes that make the programmer a more efficient unit and thus potentially saving money. This is neither the place nor the time for a full description of these, I suggest you read the comprehensive User Manual, suffice to say that it should be quite easy to precisely tailor the operation to suit your needs. One feature that does deserve a positive mention is the fact that the programmer and control unit have already been 'paired' at the factory. With the previous programmer, power outages or battery replacement sometimes necessitated resynchronising the programmer and the control unit, and this could be a somewhat fiddly and time-consuming exercise. Not so with this new version. Simply execute a Master Rest, set the programmer into continuous transmit, and then press and hold the PROG and CH1 buttons on the control unit, and in my case within a second the green LED blinked and the units were synchronised. In summary, an excellent wireless programmer and control unit, easily installed, straightforward to synchronise and program, with a clear easily read display, and, if the reliability of its predecessor is a guide, one that should give many years of trouble free operation.

Product seems just fine, and very much fit for purpose. Temperature sensing on thermostat is accurate. Programmer and receiver pre-paired, and connected immediately. Nice, clean design of both units. Has some nice features, like automatic date and time setting. The programmer literally worked on default settings straight out of the box. Probably suitable for most situations, although it lacks some of the fancy (and, probably, little-used) modes and options of more expensive units. Instructions could be a lot clearer.An important caution! If you are buying this product to fit yourself - as I did - rather than employ an electrician to fit the receiver and connect to the boiler, you need to know what you are doing and to be able to read and understand a circuit diagram. If you know how to wire a lightswitch without instruction, you are on the way. You also need to be VERY clear what the wiring connections from the boiler are. It may be reasonably obvious from the unit you are replacing (if any), as it was for me but - and I can see from comments on online forums - people not always are at all. Applies especially if the power to the receiver is a spur from the boiler, rather than a separate supply to a FCU - you may have a five-core flex to contend with! And one line in the instructions could be easily misinterpreted, and have you sending mains power where I am not sure mains power would be a good idea.Upshot is, only buy this product to fit yourself if you are confident you know what you are doing, are familiar with the wiring regulations, and are sure you know what the wiring from the boiler is. Probably to replace an existing programmer. Otherwise, get a professional to fit it. The installation instructions, including for initial setting up of the programmer where you want to change any factory defaults, are clearly aimed at professional installers - indeed, they state installation should only be by a qualified electrician or competent heating installer.Four stars not five because the above is not made clear at all before you buy.