So we have a regular combi boiler type gas boiler doing central heating and hot water. At the moment the only control we have (other than thermostat valves on the radiators) is the timer control.
What options do I have for installing a proper thermostat control into the system? Is this a job best left to the professionals?
Cheers ...
Depending on the model/age of the boiler the easiest way would be to fit a contoller with a wireless thermostat, other wise you'll have to run the cable all over the place to where you want to put it. It's about the same price (done professionally) as a wired on as it's much faster to fit. IIRC ours was literally a plug and play thing....
I'd go for a room thermostat (preferably a wireless one you can move round) - puttign the thermostat int he hall has always seemed like a complete waste of time.
Having said that - if you have rad thermostats and they're keeping the rooms at the temperatures you want is there any advantage to having an override at 'house' level?
A decent wireless thermostat (like a honeywell CM927) is easy to fit and will cost about £100.
The relay replaces your hardwired timer, the wireless thermostat is then "paired" with the relay and then can be stuck anywhere in the house. Ive installed two of them, one for upstairs rads and one for downstairs UFH (two different on call systems).
You probably need to be comfortable identifying the right connection from the relay to the boiler, checking against the wiring specs for the boiler and the relay box. If that's a bit much for you then a sparks or a plumber should be able to do it.
Wireless is a more expensive box to buy, but compare it to all the chasing and replastering a wired one might need and it comes out cheaper usually.
Having said that - if you have rad thermostats and they're keeping the rooms at the temperatures you want is there any advantage to having an override at 'house' level
Its not a bad idea to have a thermostatic switch as well as timer to call the heat regardless of the TRV settings. Means your boiler isnt being called to deliver small amount of heat when none is in fact needed anyway.
Had a Honeywell wireless one fitted a couple of months back. Paid £60 labour. I wouldn't tackle hooking it up to the boiler myself.
BTW, this is the relay wiring youd have to do (subject to the model you are connecting to)
[img] 
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It looks more complicated than it actually is. N is just a connection from supply to boiler, Two of those live wires are just bridges (one crossing from LHS to RHS) the other are the switched live A to B, and the earth is just connected and insulated.
If you have to ask, then maybe it is a job for the professionals, but it will depend on the timer/boiler setup. They are usually just 4 wires to the timer, one pair providing power to drive the timer, the other being switched according to the timer, powering the boiler startup.
If it's just a stat needed, then you'll still need to wire it to the place on the wall where you want it, living room? A quicker, neater solution, but slightly more outlay is to use a wireless stat to control the whole lot. You can also get the timer/programmer in this unit. You wire in the sender unit next to the boiler cabinet and put the main control where you want it in the house. If you go with the programmer option you bypass the timer in the combi.
About £45 for the wireless stat, add £10-40 for the programmer option.
[url= http://www.toolstation.com/shop/Heating/Controllers/Digital+RF+Thermostat+Programmable/d230/sd2732/p49080 ]http://www.toolstation.com/shop/Heating/Controllers/Digital+RF+Thermostat+Programmable/d230/sd2732/p49080[/url]
Also, once you're into the combi cabinet you're into legal/safety issue with Gas regs. Get a man in, but he shouldn't take more than an hour on the job.
This is the one we got BTW
http://www.buyaparcel.com/pageview.php?page=show_product&ecommerce_stockcode=CMT927
Recommended by the installer as he said it was the easiest to program. We bought it ourselves so he wasn't bulling us up to pay him more cash.
HtS - same as me. Been very pleased with them. I like the "Partaaayyyyy" feature too 😉
Not had a go of Partaaayyyyy mode yet. Does it make the lights flash in different colours?
Nah. It autodials PartySkanksRus and Dominos Pizza and tunes the radio into Heart FM.
Everything a partay needs.
Also, once you're into the combi cabinet you're into legal/safety issue with Gas regs. Get a man in, but he shouldn't take more than an hour on the job.
Not true,im afraid, there is no requirement to have anything to do with gas safe if all you are doing is wiring up the boiler. I have wired up literally hundreds and am not and have never been a member of CORGI or Gas Safe.
Turin, mainly correct, however if it a balanced flue boiler and to wire it up you have to remove the balanced case, then in theory you should be gas safe.
bear - if you're replacing the timer switch with a wireless thermostatic relay, you dont need to go any where near the flue case do you?
Usually no, but just be aware that is all. Generalisations can be misleading and sometimes dangerous.
last one i fitted was for a diy cockup,it cost the guy £500 by the time id replaced his blown up pcb and brand new timeclock and he had no heating or hot water for 5 days............i guess the moral of the story is to call in the profesionals at the start!
.i guess the moral of the story is to call in the profesionals at the start!
no it's not.
The moral of the story is if you have no idea, call a pro.
Its not black magic to everybody....
Stoner you are correct - the art to good diy is knowing your limits, both from a safety perspective and from a "god that looks s**t" perspective!
A tip from me:
DO NOT do up the final connections on a wired thermostat without checking that a) the power really is off and b) the timer isn't about to cick in just as you have fingers / screwdrivers on wires.
It was a very loud bang and my arm was all tingly/numb for the rest of the day....
DO NOT do up the final connections on a wired thermostat without checking that a) the power really is off
prior to change in regs was quite happy to do own wiring and stick to the regs and i guess reason regs changed was because too many "DIY property developers" didn't care a toss - one thing is never assume anything is wired into circuit its supposed to be - i always switch all circuits off - maybe put one back on if need but check for live terminals
meanwhile a numpty Q - similar need to replace a wall based stupidly positioned timer with something that will control two circuits (am splitting upstairs/downstairs with a motorised valve)
Harry_the_Spider suggested this above
[url] http://www.buyaparcel.com/pageview.php?page=show_product&ecommerce_stockcode=CMT927 [/url]
looks ideal - any comments
the honeywell relay can be used to control the boiler call for heat, a pump or a valve, or any of the three. Its just a switch driven by time and temp really.
I [i]think[/i] you can pair more than one wireless sender with a relay receiver but Im not 100%
Will one heating circuit be always open and the valve just open to the second circuit on call? Which circuit controls the call for heat, or will both?
A decent wireless thermostat (like a honeywell CM927) is easy to fit and will cost about £100.
I've just fitted one of these too and it's marvellous. The best feature for me is the ability to set different temperatures at different times.
** wanders off to investigate the party feature!
*heavy bass and strobe light emanates from geoff's house*
its nice having the control it gives you. We work from home and have wholly underfloor heating throughout the downstairs so it's very handy to be able to subtly control the amount of energy we sink in to the floor over the day without it getting to warm, or letting it get cold and then having a timelag before the room is upto comfort temperature again in the evening.
- i'm think the one Harry the Spider suggested will do thisStoner -
I think you can pair more than one wireless sender with a relay receiver but Im not 100%
Will one heating circuit be always open and the valve just open to the second circuit on call? Which circuit controls the call for heat, or will both?
thanks thats the question i need to ask the guy whose given me all the bits (putting underfloor heating on ground floor) said just get a wireless controller and relay for underfloor part but ideally i want to lose the existing timer while i'm doing it and got to fit a valve to isolate upstairs
party mode - looks like should read swinger mode !
antigee - I have one of those honeywells on the UFH and one upstairs on the rads.
However, I have a buffer tank (very, very large water tank that has its own thermostats monitoring tank temp that call for heat from the biomass boiler as opposed to thermostats in the house that call for heat based on air temperature) from which hot water is called by the relays (which drive pumps only) which themselves are controlled by the two thermostats independantly.
Its a little bit trickier for you I think because you have to factor in calling the boiler to fire as well as pumps to run.
I’d just like to point out that I didn’t suggest it. The guy who was paid to fit it suggested it because a) He could fit it easily (only costing me £60, not double or treble that) and b) It is an easy unit to operate. However I am prepared to take the credit if you decide to buy one and are as pleased with it as we are. 😉
At the previous house we had an Alpha one which was a bit of an ugly lump and not the most intuitive to program. Our Honeywell is linked to a Vailant boiler. The Vailant controller is apparently bloody awful to operate.
Thanks for your tips all!
I think it is going to be a bit beyond my level of skill/bravery so I spoke to my friendly plumber yesterday and he recommended I go ahead and buy one and he'll fit it.
His suggestion was that I don't get a [u]programmable[/u] wireless thermostat, instead get a wireless thermostat - what does the hive mind think? I reckon I'd like to still tell it to come on at a specific time but is that negating the point of a thermostat and going back to what I had before?!
His suggestion was that I don't get a programmable wireless thermostat, instead get a wireless thermostat
Just out of interest did he say why?
His suggestion was that I don't get a programmable wireless thermostat, instead get a wireless thermostat - what does the hive mind think? I reckon I'd like to still tell it to come on at a specific time but is that negating the point of a thermostat and going back to what I had before?!
I don't understand his logic. Mine is wired in such a way that you can use the existing stat and controller, or the wireless one (which also acts as controller for downstairs). For the sake of an extra few quid, go with the programmable one, you can always just stick it at one temperature.
No he didn't give a reason why, and it was only once I'd thought a bit more about it that it seemed a bit odd ...
go programmable. For the relatively small additional cost, the flexibility to control both the time and temp at different times of day/week will probably pay you back in energy savings in not too long a time.