Radiators on manifold with room stats

[shaun2345]

Hi

I am looking at running a 8 port manifold system from my Combi boiler to each rad then using electric valves and thermostat in each room to control the valves,

Any advice anyone who has done this ?

What pipe to use as under floor heating Pipe I was going to use is 16mm not 15mm

I know I will use more pipe than a normal loop system but I have better control over the zones etc .

Any pros or cons from anyone ?

Shane

 

[MeldrewsMate]

Perfectly feasable, points to note are:-
1. As noted, more pipe will be needed, this pipe will also heat the route to the final location.
2. You'll need 16mm radiator connections; perhaps better to run 15mm pipe and use 15mm cone adapters at the manifold end?
3. Lots of wiring from stat to manifold, or need for flex to electric valve at each rad.
4. Control action will be ON-OFF, even mechanical TRVs have better modulation!
5. Your system as described will not meet the building regs' requirement for TRV to each rad.
6. Proprietary wireless rad controls will do the job better, are more easily expanded/changed, but need batteries.

MM

 

[ianmcd]

Be much cheaper and easier just to fit smart TRVs

 

[shaun2345]

Perfectly feasable, points to note are:-
1. As noted, more pipe will be needed, this pipe will also heat the route to the final location.
2. You'll need 16mm radiator connections; perhaps better to run 15mm pipe and use 15mm cone adapters at the manifold end?
3. Lots of wiring from stat to manifold, or need for flex to electric valve at each rad.
4. Control action will be ON-OFF, even mechanical TRVs have better modulation!
5. Your system as described will not meet the building regs' requirement for TRV to each rad.
6. Proprietary wireless rad controls will do the job better, are more easily expanded/changed, but need batteries.

MM

Thank you

Yes it will be more pipe but the pipes at the mo are crazy so I need to replace this way will also allow me to start getting some rads live while I’m still working on the rest of the house .. the pipes will for most of the runs go in bunches of 6 so I will crap in some insulation ..

Ok so run routes in like jg speedfit 15 mm and the use a 15mm to 16 mm adaptor them a small piece of 16mm from adaptor to manifold ?

I would either use witless thermostats a or thinking now I might just stick with conventional trv valves they have worked for years so prob stick with them

Do you think 10mm or 15 mm pipes will be better from manifold ?

Any advice on good 8 port manifold ? I will use the bathroom rad with just lock shield valves fully open as a pass through ..

Regards shane

 

[shaun2345]

Be much cheaper and easier just to fit smart TRVs

Thank you yes I’m thinking that now but still want to go with the manifold system it’s easier to isolate if required and allows me to build system as I go as I’m doing one room at a time I can setup rad in room one then run pipes to room 2 and three and only connect these when required ..

Shane

 

[Madrab]

I will use the bathroom rad with just lock shield valves fully open as a pass through

Pass through...for what? If it's a bypass then that's not really acceptable practice anymore, if the boiler needs a bypass then it should have one fitted to the system properly.

As suggested, it's a bit overkill, why go to that extreme and complication? What temps are you planning to run the system at? I presume you won't be using a separate pump and mixing valve then? Will you be able to centralise the manifold otherwise you could end up with quite uneven pipe run lengths.

You do get 15mm eurocone manifold adapters so 15mm pipe could easily be used.

 

[shaun2345]

Pass through...for what? If it's a bypass then that's not really acceptable practice anymore, if the boiler needs a bypass then it should have one fitted to the system properly.

As suggested, it's a bit overkill, why go to that extreme and complication? What temps are you planning to run the system at? I presume you won't be using a separate pump and mixing valve then? Will you be able to centralise the manifold otherwise you could end up with quite uneven pipe run lengths.

You do get 15mm eurocone manifold adapters so 15mm pipe could easily be used.

Hi

Ok I thought you needed an rad that was not on a trv anymore but that’s fine as the bathroom is quite small yes a trv would be better ..

Yes it will be quite central in the house so Pipe runs should no be too bad for distance .

Not planning on extra pump was going to rely on the one in the boiler to circulate

This is something I thought about in the other house and never moved forward and as I have the floors up right now and seen the mess of the pipes in this house I thought now is time to tidy them with a manifold and it allows ease of control over rooms as I do them instead of having to drain and refill each time I complete a room so I can add rads and remove rads on our refit plus if I need I can just isolate a circuit in future ..

I know the cost is more than a ring type system but with the right gear it works well in my head

Shane

 

[Madrab]

The other cost will be the stats for each room, if that's what you're planning and either hard wired (with 240v/12v) back to actuators on the manifold or wireless to a control unit @ the manifold.

 

[DP]

Manifold idea would work but a bit Heath Robinson.

Better to do conventional with TRVs that will take smart heads. Main flow and return can be extended as your schedule progresses
Best bit about likes of Evohome kit is that it will move with you if you move home. Expensive but utterly flexible. Have one and have installed many.

 

[MeldrewsMate]

...so I will crap in some insulation ..

I'm not sure that will assist its insulation properties, but it's your house

Manifold idea would work but a bit Heath Robinson.

Better to do conventional with TRVs that will take smart heads.
Evohome kit...and have installed many.

Agree that the roomstat operating a radiator in ON-OFF mode would lead to wide room temperature swings once the radiator heating inertia and rad to air heat transfer inertia came into play - at least a manual TRV gives some degree of proportional action.
@shaun2345 consider using modulationg TRVs at each radiator, and ON-OFF actuators at the manifold. This way you could later program (switch electrically) each room heating on or off independantly, but have decent room temperature control when ON.