Hi, I've got 11 radiators over 3 floors. Those at the top struggle to get warm enough given the boiler is located on the ground floor, and will continue to pump water to the ground floor radiators even when they're hot enough. The simple solution would to install Wiser thermostat valves (we have a Wiser system in place) so floors/zones can 'switch off' when the desired temperature is met, and hot water more evenly distributed to hose much needed radiators on the top floor. Question is, how many Wiser thermostat valves would I actually need? There are 5 radiators on the ground floor, but it's very open plan (i.e. one big 'zone'). We have 4 on the middle floor, but located in bedrooms respectively. The top floor bedrooms have 1 a piece. Need a little guidance before I shell out for 11 thermostat valves at £45 a piece (!)....huge thanks.
Wiser Thermostats...how many?!
- Thread starter Duds138
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MGW
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The linked TRV's are used in rooms where due to wind, sun, or timings they are cold when the wall thermostat has turned off the boiler, so maybe two or three are required, to keep boiler running when for example the sequence set has turned off lower floors, but upper floors still used.
So the coldest bedroom with have a linked TRV, the other bedrooms can have a simple programmable TRV set to same times as the linked one.
However in theory if set up correctly you should never get what you describe. So it seems your system needs setting up.
We are told to use a differential thermometer and set the radiators so each one has around 15ºC between feed and return, but I don't have to hand a differential thermometer, so I tried turning off each radiator in turn on the lock shield valve, starting closest to boiler, and then turning on until feed pipe got just warm. Over time the radiator would clearly heat up more, but likely it would still need some tweaks.
My TRV heads showed target and current.
So if target was under current then closed the lock shield a tad, and if target for a hour or two over current opened it a tad, and slowly I got it so every room spot on. One leaving the house the electronic heads were replaced with standard heads, and still rooms spot on.
So if the TRV head shows the target and current it can be moved from radiator to radiator to fine tune them. However these eQ-3 heads
cost me £15 each, for bluetooth version, the non bluetooth was cheaper, got them 3 years ago, the Terrier i30 also a stand alone programmable TRV head, so likely two or three linked heads, and rest simply unlinked programmable heads.
However the Drayton Wiser head does have another trick up its sleeve, the algorithms are claimed to work out how fast a room heats, so it can leave reheating a room to last minute, so if using geofencing those rooms which heat up first ready for your return will need the Wiser heads.
So the coldest bedroom with have a linked TRV, the other bedrooms can have a simple programmable TRV set to same times as the linked one.
However in theory if set up correctly you should never get what you describe. So it seems your system needs setting up.
We are told to use a differential thermometer and set the radiators so each one has around 15ºC between feed and return, but I don't have to hand a differential thermometer, so I tried turning off each radiator in turn on the lock shield valve, starting closest to boiler, and then turning on until feed pipe got just warm. Over time the radiator would clearly heat up more, but likely it would still need some tweaks.
My TRV heads showed target and current.
So if target was under current then closed the lock shield a tad, and if target for a hour or two over current opened it a tad, and slowly I got it so every room spot on. One leaving the house the electronic heads were replaced with standard heads, and still rooms spot on.So if the TRV head shows the target and current it can be moved from radiator to radiator to fine tune them. However these eQ-3 heads
cost me £15 each, for bluetooth version, the non bluetooth was cheaper, got them 3 years ago, the Terrier i30 also a stand alone programmable TRV head, so likely two or three linked heads, and rest simply unlinked programmable heads.However the Drayton Wiser head does have another trick up its sleeve, the algorithms are claimed to work out how fast a room heats, so it can leave reheating a room to last minute, so if using geofencing those rooms which heat up first ready for your return will need the Wiser heads.
Hans_25
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Don’t really understand the question. I have Wiser here with iTRVs on every rad except hall and bathroom. Room stat in lounge which has 2 rads and overrides the 2 individual iTRVs.
You could use fewer iTRVs so those rads form the “control” for a floor I guess, keeping the boiler on until they’re up to temperature. Do you have any zones plumbed in?
You could use fewer iTRVs so those rads form the “control” for a floor I guess, keeping the boiler on until they’re up to temperature. Do you have any zones plumbed in?
So we have 11 standard rads, but most without thermostats. We only just had a Wiser room thermostat fitted in the hall downstairs, but the boiler still works in a “binary” manner ie its all on, or all off. So set the temperature for 18 degrees on the room thermo and the whole house heats up, until the thermo switches off at 18 (and the boiler stops). We had another floor built (an ambitious loft conversion) where two more rooms with rads were built. The issue now is those rooms never heat up enough cause the boiler has so far to pump the hot water, and it’s too busy continually pumping hot water into the lower floor rads…until the thermo tells it to switch the whole system off.
Hence we need smart TRVs, so the boiler keeps running, but the lower rooms/‘zones’ switch off when those smart TRVs reach temp. Question I had was do I need one on every rad, or is there a smarter way ie one per room which will switch off, given the hot water a greater chance of getting to the top floor….(?!)
Hans_25
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You could install one or two iTRVs in that top floor, this will keep the boiler turned on until everything including those rooms are up to temperature. Downside is that unless you have Manual TRVs on other rads, the whole house will continue to heat.
in the same way you could buy a wiser room stat (I think this will work the same way) and put that in the loft room.
ideally you’d put iTRVs on every rad for full control. If you don’t have at least manual TRVs on all rads already I’d say this is your best route. Could buy an extra room stat to play with, can always add that later. Or move the hall room stat to upstairs.
in the same way you could buy a wiser room stat (I think this will work the same way) and put that in the loft room.
ideally you’d put iTRVs on every rad for full control. If you don’t have at least manual TRVs on all rads already I’d say this is your best route. Could buy an extra room stat to play with, can always add that later. Or move the hall room stat to upstairs.
This is so helpful, thanks. I think I have an idea how to do this. Might as well leave the main stat on the ground floor, but install 3x iTRVs (its open plan) and manuals on the hall radiator. Then 3x iTRVs on the middle floor in just the bedrooms, and then 2x iTRVs in the two loft rooms. Logically, once the ground floor comes to temp then 3 rads off will be enough to boost the pressure to the middle floor, and when at temp those rads go off there should be more than ample pressure to get the loft rooms (where the kids sleep) up to temp.
Not sure on whether I need a room stat on the top/loft floor, given it will only work if there was enough pressure to get the hot water up the house...meaning the lower floor stat would need to be off/low temp...or have I got that totally wrong? Welcome the advice. But for now, I think 8 iTRVs should do it.
Hans_25
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Room stats need to be assigned to a room, and if that room also has a rad with iTRVs then it will override them. Not sure why you would put a room stat on the 2nd floor when both rooms have an iTRV?
I have an additional room stat in my lounge, but it has 2 rads both with iTRVs so overrides both and turns both rads on/off together.
The boiler will come on if any room stat or iTRV calls for heat, so every rad needs some kind of TRV really, except for perhaps the hall rad or a cold room.
I have an additional room stat in my lounge, but it has 2 rads both with iTRVs so overrides both and turns both rads on/off together.
The boiler will come on if any room stat or iTRV calls for heat, so every rad needs some kind of TRV really, except for perhaps the hall rad or a cold room.