Central Heating - replacing one modern rad with two cast iron

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Hi All

Room revamp and I am required to take out a functional modern double radiator and put two cast iron reclamation 'old skool' rads more as decoration compared to a heat source (but we will see). We have a newly installed woodburner in the room as the main heating source.

Rads have been stripped and will need painting however my question here is about taking the pipe work to the single modern rad and feeding the two cast iron rads.

I have sourced flanges, bushes, adapters and valves but can I simply put a T-piece on the current hot water flow to feed the two rads and then do the same on the return from the two rads to complete the loop?

Have never done plumbing and will be doing some soldering practise well beforehand but hey thats whay DIY is all about!!
 
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The TRV and lock shield valve adjustments can ensure the radiators work OK, but clearly the old radiator holds more water than modern so with header tank there should be enough room for extra expansion but with a sealed system you will need to check.

Heat wise the less water a radiator holds with a modulating boiler the better, as it will heat up and cool down faster, so with Myson fan assisted radiators from point when boiler fires to point when they are delivering full 3 kW of heat into the room is very short about 10 minutes, but with cast iron radiators that time will increase to ¾ hour. The same when the programmable TRV decides that room wants more heat, with Myson fan assisted min to max output takes around 30 seconds for fan to get to speed, with a cast iron radiator likely 10 minutes, also getting heat into the room is also slower, so any idea of geofencing goes out when fitting cast iron radiators.

I would love to replace living and dinning room radiators with Myson fan assisted however the control is a problem as it does not use TRV heads no so bad with oil where boiler does not modulate, but the building management system becomes expensive so stuck with panel radiators for foreseeable future. It takes around 1½ hours for my house to warm up, so heating has to be switched off/on manually or timed. If that time could be reduced to ½ hour then could use geofencing.

So I have to manually get out my phone and set heating to come on before I start on my way home.
 
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can I simply put a T-piece on the current hot water flow to feed the two rads and then do the same on the return from the two rads to complete the loop?

Fundamentally yes that's what happens but the size of the column rads and the pipe size will dictate what's needed. If they are big then a single 15mm F&R may not have the capacity to feed both sufficiently.
 
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