Apologies for the long question but I need advice please on a couple of things please.
Currently, I have an oil fired central heating system where the boiler and stored hw is controlled by a Honeywell ST799 programmer in the airing cupboard and a mechanical rotary honeywell thermostat on the landing, close to the stairwell. Stored hw linked to a cylinder stat.
It has never been easy to regulate the central heating temperature because of its location but the stat is now on its way out so I want to upgrade.
The best thing seems to be the Honeywell Sundial pack 2 but as the programmer would ordinarily replace the ST799 in the airing cupboard, I’m concerned that I could not fit the new wireless programmer far enough away from pipework and buried wiring to make sure the wireless signal is not compromised.
The alternative is to have a standard 2 channel programmer linked to a wireless stat where the receiver replaced the existing stat outside the airing cupboard.
So.. first question: would a wireless honeywell Sundial programmer be ok in the airing cupboard in terms of interference?
Also, can anyone tell me the difference between the Honeywell Homexpert range of programmers THR860 and wireless stat THR872 compared to the standard ST9400C 7 Day 2 Channel Programmer / Wireless enabled programmer (ST9420C) / Wireless room thermostat (DT92E)? Is it just looks and price or is one range better than the other?
If the Sundial programmer is not an option in the airing cupboard, the Homexpert range may be a better idea in terms of looks.
Thanks in advance.