Fitting Drayton Wiser kit and bypass valve

[Derek M]

I want to fit this Drayton Wiser kit (with three additional TRVs) in my parent's 3-bed semi. Combi boiler is in the kitchen, along with a small radiator, and adjoining the kitchen is the through living room and dining room, with a full-size radiator in each. Upstairs there's full-size radiators in the two main bedrooms, and smaller ones in the boxroom and bathroom.

https://www.draytoncontrols.co.uk/products/Smart-Heating/Wiser/wiser-multi-zone-kit-1-0

I prefer the Drayton Wiser over the Tado kit, because it's cheaper, the display on the thermostat is more informative and easier to read, the Tado locks several features behind a £3/month subscription and the TRVs are supposedly noisier than the Drayton ones.

Keeping the Smart Thermostat in the Living Room/Dining Room should be sufficient to control the two radiators there, so they won't need TRVs and I'll just need to fit TRVs on the four radiators upstairs and the one in the kitchen.

I understand that I need a bypass valve on one of the radiators. Is there any particular type of bypass valve I need to get, or can I just use the cheapest one I can find, and does it matter which radiator I fit it on?

Should I fit the bypass valve first, before fitting the Wiser hub in the hall in place of the existing digital thermostat and then fitting the TRVs?

 

[Mottie]

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[CBW]

You have a combi boiler, which may have a bypass valve in it. What make/model combi?

 

[ianmcd]

You say you will have two radiators without TRVs they are the by-pass, no need to fit another

 

[CBW]

You say you will have two radiators without TRVs they are the by-pass, no need to fit another

Again, I didn’t read it properly

 

[Derek M]

You say you will have two radiators without TRVs they are the by-pass, no need to fit another

Oh right, seems obvious now you've said it! Thanks.

 

[oldbutnotdead]

Be a little wary here- unless the living/dining room is on a zone valve you'll be heating that room every time any of the wireless TRVs calls for heat, which is probably not what you had in mind.
Without any zone valves, the only way to get full controllability of each room is to have wireless TRVs on every rad (and then, depending on your boiler, you may need that bypass).
If you do need a bypass, it is generally best to fit it a few pipe metres away from the boiler (greater volume of water so quicker cooling of the boiler)

 

[Derek M]

Be a little wary here- unless the living/dining room is on a zone valve you'll be heating that room every time any of the wireless TRVs calls for heat, which is probably not what you had in mind.
Without any zone valves, the only way to get full controllability of each room is to have wireless TRVs on every rad (and then, depending on your boiler, you may need that bypass).
If you do need a bypass, it is generally best to fit it a few pipe metres away from the boiler (greater volume of water so quicker cooling of the boiler)

Thanks. That makes sense but I'm back to being confused again now. If I need to fit TRVs on the living room/dining room radiators, doesn't that make the thermostat utterly redundant, as each radiator will effectively have its own thermostat which can turn the boiler on/off?

I could use the five TRVs that I've ordered for the three bedrooms and the living/dining room radiators, and leave the small bathroom and kitchen radiators without, so I won't need a bypass valve and the bathroom and kitchen radiators will be on whenever one of the other radiators is on, which makes sense because if the other rooms are being used and heated, people are probably going to be visiting the kitchen or bathroom. I don't see how the thermostat serves any purpose in this setup though.

 

[ianmcd]

Thanks. That makes sense but I'm back to being confused again now. If I need to fit TRVs on the living room/dining room radiators, doesn't that make the thermostat utterly redundant, as each radiator will effectively have its own thermostat which can turn the boiler on/off?

I could use the five TRVs that I've ordered for the three bedrooms and the living/dining room radiators, and leave the small bathroom and kitchen radiators without, so I won't need a bypass valve and the bathroom and kitchen radiators will be on whenever one of the other radiators is on, which makes sense because if the other rooms are being used and heated, people are probably going to be visiting the kitchen or bathroom. I don't see how the thermostat serves any purpose in this setup though.

You are correct just do as you proposed

 

[Derek M]

OK, thanks. It's a shame they don't sell a kit without the thermostat for people who don't need it.

 

[oldbutnotdead]

The room stat can still be used with the WiFi valves- in the app you can link it to the rads in question (in your case the big front room) so you can control that room temperature without the app (when room stat achieves setpoint it tells the linked WiFi valves to close ). But I agree, if you go the whole house route the room stats are a bit redundant

 

[Derek M]

The room stat can still be used with the WiFi valves- in the app you can link it to the rads in question (in your case the big front room) so you can control that room temperature without the app (when room stat achieves setpoint it tells the linked WiFi valves to close ). But I agree, if you go the whole house route the room stats are a bit redundant

Hmm, maybe not completely redundant then. I mean, most people will probably be happy just to use the app to control the temperatures for each room and my elderly parents are comfortable using apps, so the thermostat isn't really necessary, but I guess with the living room/dining room they may want to lower the radiator temperature when they have groups of friends round, thus raising the room temperature with their body heat, and having the thermostat will make it a bit easier to control the radiators. With the bedrooms, they probably won't need to adjust the temperature once they've got it dialled in.

 

[oldbutnotdead]

Main thing I use mine for is if I'm having a late one and want an extra blast of heat in that room, tbh Alexa is a much better mechanism

 

[Derek M]

Main thing I use mine for is if I'm having a late one and want an extra blast of heat in that room, tbh Alexa is a much better mechanism

My parents have an Echo Dot in the living room which they use a fair bit, so I'll show them how to use that to get extra warm in due course.

It turns out the current thermostat in the hall is a RF unit, with no wiring to the boiler or mains, so the Wiser hub will have to go in the kitchen next to the boiler but that shouldn't be a problem. It's a Worcester Greenstar 34cdi classic and I assume the cover will have to come off so we'll need a registered gas engineer to wire it up rather than an electrician?

 

[ericmark]

I was told one radiator in room with the wall thermostat does not have a TRV however it was when I fitted the TRV in the hall the heating system in my mothers house started to work as expected.

But my own house it did not work, the hall cools too slow.