Control heating when not at home

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We have an oil fired boiler for our house which provides radiator heating and hot water. The system cannot heat the hot water independently of the radiators. There is no thermostats controlling room temperatures. All the radiators have thermostatic radiator valves. The heating on/off is controlled with a mechanical timer where pins are pushed in or pulled out to set on/off times for the heating to operate.

I'm starting to look into modernizing the existing system. I would like to have a wireless thermostat which could control the room temperature and the ability to turn the heating on remotely when away from the house.
 
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Hive. Not sure but with the system you have, you might only need the single channel version. I’m sure someone else will confirm this.
 
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I am slightly surprised that the heating does not have rads only and h/w...Are you heating the tank with electricity when the heating is off and I will assume that you control that via a a simple switch for the immersion.

Personally I would invest in a 3 port valve for the heating and get the ch/hw divorced given that electricity prices will be rising faster than heating oil in the coming months.

Hive non combi are all dual channel CH and HW.. without a 3 way port the h/w control will be useless. There are other wireless controllers out there.
 
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We have an oil fired boiler for our house which provides radiator heating and hot water. The system cannot heat the hot water independently of the radiators. There is no thermostats controlling room temperatures. All the radiators have thermostatic radiator valves. The heating on/off is controlled with a mechanical timer where pins are pushed in or pulled out to set on/off times for the heating to operate.

I'm starting to look into modernizing the existing system. I would like to have a wireless thermostat which could control the room temperature and the ability to turn the heating on remotely when away from the house.
Do you have a motorised 3-port (or 2 1-port) valves? My guess is you haven't, in which case you need rather more than a wireless thermostat to modernise the system.
 
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The house is a terraced house built in the early 60's. The oil boiler is a Honeywell Boiler with a thermostat on the top of it allowing the temperature to be set between 65 and 90. There is one pump in line from the boiler to circulate the water through the system. This heats both the radiators and the copper hot water tank upstairs.
 
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The house is a terraced house built in the early 60's. The oil boiler is a Honeywell Boiler with a thermostat on the top of it allowing the temperature to be set between 65 and 90. There is one pump in line from the boiler to circulate the water through the system. This heats both the radiators and the copper hot water tank upstairs.
Can we take it from that, that you don't have a motorised 3-port (or 2 1-port) valves?
 
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I'm not really sure what that is but I'm probably correct in thinking that no we do not have one
 
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you have a gravity hot water system with pumped central heating, if you want to use the CH without the HW no programmer will do that,you require pipe work alterations and the addition of system controls if you are happy with the current set up and just want to control remotely just get a hive dual channel or similar that supports gravity HW systems
 
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I do have internet linked TRV heads and wall thermostat, however with an oil fired boiler they are not as good as with last house which had a modulating gas boiler.

The TRV and wall thermostat are not linked. Which is a pity, but Nest withdrew support for Energenie TRV heads.

It runs on a C Plan so can have DHW without central heating, but not central heating without domestic hot water.

I fitted Nest Gen 3 in the main as only two wires between main house and garage converted into a flat, and Nest allowed it to be powered and control but CH and DHW with two wired at extra low voltage.

However the problem is the hall cools too slowly, yes cooling not heating is the problem, if the hall over heats by slightest amount, then before it turns on the CH living room is too cool.

I fail to understand what a wall thermostat is for? The TRV's are all programmable and the rooms will reach correct temperature without a wall thermostat, so really what I need is for a relay to be switched on if any TRV requires heat, there is no need for anything to measure room temperature all it needs to do is switch on/off when the TRV's require it to.

So we have 4 TRV's in major rooms all connected to internet, all which tell my PC, tablet or phone when the boiler needs to run, and they can all connect to the wall thermostat and tell the boiler when to run, but it needs a human to read the data and transfer it from one program to another it make it work, how daft.

It seems Evohome, Wiser, tado and even Hive can transfer data between TRV and hub/wall thermostat, but not Nest.

But the main control is the TRV, the hub/wall thermostat is a dumb termial really.

From what I read the Drayton Wiser TRV has the best algarithums so seems likely that is the best system. However it is how to control the boiler, Nest is volt free, so easy to configure, but Wiser is not, neither is Hive, but Hive has a software work around.

Twin channel Hive one contact to pump and one to boiler, it switches on both for CH and just boiler for DHW on it's own.

The problem is Hive stops taking a demand for heat over 22 degs C, so needs to be in a room kept cool, like the hall, also like Nest seem to drop support at the drop of a hat, they have just said dropping support for their door bell.
 
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Not so Hives range is 5-25C
I know it was going to be altered, did not know it had been done, but 5-25C seems wrong, why would they allow you to set hive not to accept a "demand for heat" at 5 degrees? We are talking about the "demand for heat" not what the dial can be set to, so it was if the wall thermostat was 22 degs or warmer, it would not take a "demand for heat" from the TRV head, wonder when it was changed?
 
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I fail to understand what a wall thermostat is for?
In a normal system it stops the boiler cycling and turns it off when the room stat temp is reached. You must know that?
 
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I know it was going to be altered, did not know it had been done, but 5-25C seems wrong, why would they allow you to set hive not to accept a "demand for heat" at 5 degrees? We are talking about the "demand for heat" not what the dial can be set to, so it was if the wall thermostat was 22 degs or warmer, it would not take a "demand for heat" from the TRV head, wonder when it was changed?
5C is the frost protection setting
 
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In a normal system it stops the boiler cycling and turns it off when the room stat temp is reached. You must know that?
I of course must agree with the anti-cycle function, but the problem is to work, the two thermostats need to be very carefully matched, if the TRV turns off too soon the wall thermostat will not work, and too late the latent heat collection is messed up. I know in my own hall the temperature 1.5 meter from front door and 300 mm high (TRV) is between 2 to 4 degrees lower to the temperature 5 meters from front door and 1.5 meters high, it is not being different which is the problem, but the variation between the two changing.

My computer shows TRV temperature,
1658257800180.png
so all it needs is an IFTTT command, it this (current equals or exceeds target) then that (switch off boiler) would be better maybe other way around, if any target exceeds any current then run boiler.

There should be no need for a thermostat on the wall, just a hub to collect information and act upon it.
5ºC is the frost protection setting
The question was when did they change the limit for the "Heat on Demand" function. This links with what I was saying to @denso13 the thermostat function of the Hive wall thermostat is really to stop the room over heating if the TRV fails, under normal circumstances the wall thermostat does not set room temperature, it is set lower than required so if the batteries fail in the TRV it will still keep other rooms supplied with hot water, but it is the "Heat on Demand" function which does the real work, so if any TRV demands heat the boiler will run, even if wall thermostat is over the set temperature, so the TRV heads actually set room temperature, the wall thermostat function is only a fail safe.

There was talk about allowing the user to set the upper limit, but as far as I knew, it was set to 22ºC after which the heat on demand function stopped working. You could set the thermostat higher, but this would result in the heat on demand function being in essence disabled.

As long as the wall thermostat is put in a room not normally going to exceed the 22ºC this is not a problem, i.e. the hall, but it is possible a living room could exceed the 22ºC.

Setting a TRV is maybe easy with a differential thermometer, we are told around 15ºC difference between feed on return, but with just the computer recorded temperature it takes some time using trial and error to get the room up to temperature quickly but not over shoot, all down to the lock shield valve setting. If the flow is too high the radiator gets too hot before the TRV can close, and it over shoots, and if to low room does not reach temperature, but once set the radiator never really reaches full temperature and neither does it fully cool down when using a modulating boiler, the boiler and TRV's work together removing nearly all the hysteresis associated with an on/off thermostat, as they gradually open or close.

Does not work quite so well with an on/off boiler, but still works.

What seems uncertain is what if any gain is there with a correctly set up set of TRV heads, and an OpenTherm link to boiler?
 
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There should be no need for a thermostat on the wall, just a hub to collect information and act upon it.
There should be no need for over the top fancy TRV heads.

I have a room thermostat, trv's on radiators and a properly sized system. It works perfectly well and doesn't need monitored by a computer.
 

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