Home heating - smart tech and old 'conventional' system options

Caporegime
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Sorry for the long winded title.

Have an old conventional heating system.
Tank in the loft etc with separate hot water and central heating.

Also, biggest issue. The thermostat is terrible. If you set it to 22..it won't come on until its about 18c and won't turn off until 25.

So basically the house goes too hot to too cold.


2 question, hopefully separate!

1) Is it possible/how easy is it to add a smart thermostat to the existing installation?

2) is it worth changing to a combi? I know outlay is minimum 2.5k!

Few details :
-Mains water pressure is low
-Currently have hot water on for only an hour a day
-Central heating is on about 8 hours.
-very very low hot water demand, electric shower, dishwasher, cold fed washing machine
-boiler as old as house most likely (20 years)
- house is a 3 bed detached. All rooms get used during the day.
-2 adults


By far the most important thing would be getting a better thermostat!
 
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Associate
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Tado will do it fine. For hot water you will need the extension kit though. I have had Tado on 2 systems (tanked and combi) and it works just fine. People at work have it too and have it control their hot water (I never had it on the tanked system and just did the CH with it)
 
Caporegime
OP
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Tado will do it fine. For hot water you will need the extension kit though. I have had Tado on 2 systems (tanked and combi) and it works just fine. People at work have it too and have it control their hot water (I never had it on the tanked system and just did the CH with it)

Yes I did see that. I was actually surprised how cheap it was. Only disappointment is the main unit looks a bit 'meh' compared to hive, nest etc.

One question. Do the trvs tell the main unit to completely turn off the heating if all trvs are reading their cut off temp?
Ie if all rooms are set to 20c and they are all 21 does the boiler turn off? Ie its not just on with all the valves closed?
 
Permabanned
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Certainly the thermostat can just be replaced with a modern accurate one.

Nothing wrong with an old boiler! In my humble opinion combi boilers are a pain in the butt. Especially retrofitting them, they can lead to all sorts of hidden costs. No, in most cases what you need to do is upgrade your control system. Control has moved on a lot in the last 20 years. Just by upgrading the electronics, thermostats and so on you can make a huge difference.
 
Soldato
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Don't get a combi. You have a tank because the pressure is too low.

I had a 30+ year old boiler I attached a Hive to. Was brilliant.
 
Caporegime
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Don't get a combi. You have a tank because the pressure is too low.

I had a 30+ year old boiler I attached a Hive to. Was brilliant.

Yes. This is what I've been researching. I wondered why there was a tank and looks like its most likely due to the pressure.
 
Soldato
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Yes. This is what I've been researching. I wondered why there was a tank and looks like its most likely due to the pressure.
Yap. And whilst it feels "old school", it is perfectly normal and conventional.

Your shower should be a million times better than most peoples combi-only system, too. If it isn't get yourself a proper shower pump on it!
 
Caporegime
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Certainly the thermostat can just be replaced with a modern accurate one.

Nothing wrong with an old boiler! In my humble opinion combi boilers are a pain in the butt. Especially retrofitting them, they can lead to all sorts of hidden costs. No, in most cases what you need to do is upgrade your control system. Control has moved on a lot in the last 20 years. Just by upgrading the electronics, thermostats and so on you can make a huge difference.

Was hoping I could replace the stat, get the hot water control bit and do it myself. Certainly doesn't look difficult from vids.
 
Soldato
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For what it's worth, Hive come up on Amazon all the time with installation included. I think I paid £120 all in. I had the same system as you did. BritishGas did the fitting. As long as you have the "third wire" I think the chap mentioned, it is a 20 minute job.

I then added the Hive TRVs and have only the nursery set to trigger the heating to come on.
 
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Was hoping I could replace the stat, get the hot water control bit and do it myself. Certainly doesn't look difficult from vids.

No it really isn't. Most control systems come with "idiot proof" instructions. You have to remember that there will always be a first time installation for a plumber so they need good instructions too.
 
Associate
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Was hoping I could replace the stat, get the hot water control bit and do it myself. Certainly doesn't look difficult from vids.

I did my Tado myself on 2 separate houses. 1st time I had an electrician and plumper there (dad and neighbour) who told me it was wrong. It was fine. You put in what you have in their site and it gives you step by step to get it going and do the wiring.

If you don’t have Tado TRVs then the boiler will keep running until the main unit at temp but each room will control itself based on TRV. Tado TRVs can tell the boiler to fire themselves if needed.
 
Soldato
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My setup is very similar to you though the boiler is only about 5 years old. I had a dodgy thermostat too, replaced it with hive myself and it's been honestly fantastic. Never missed a beat and so handy you can control it from the phone. Was lucky that the wiring was basically a like for like with the control system was there so it was easy enough to do myself. Would recommend this forum if you need any extra expertise, some very knowledgeable and helpful blokes on there
Plumbing and Central Heating | DIYnot Forums
 
Capodecina
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Does a Hive system HAVE to be connected to the Internet to function properly or can it work through a stand-alone Modem/Router that is NOT connected to the Internet but which does include DHCP?
 
Soldato
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Does a Hive system HAVE to be connected to the Internet to function properly or can it work through a stand-alone Modem/Router that is NOT connected to the Internet but which does include DHCP?
Has to be internet connected for any meaningful function. You can hit the override button the control box (not the receiver) for on/off hotwater or heating though.

Has been a real nightmare as I've had very poor internet 9-5 the last 9 months or so due to over subbed network on Virgin.
 
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