Draining thru Micro bore pipe

[AndyBill]

my CH system has 22mm which does a loop upstairs with micro bor coming off to upstairs rads , also micro bore drops down to all downstairs rads,

im planning on adding a rad downstairs but wondering wether draining down system might block the microbore pipe with sludge.

or would it be better to turn off all the rads and just drain the pipework?

any advice would be good to an old duffer like me

 

[wonderb0y]

Drain down deffinatly. Then add your rad, if you've got a combi fill using the filling loop to top up the system, making sure to add a decent inhibitor.

If your on gravity then I'd back fill the system off mains pressure, basically connect a hose to a cold water tap and fill it up, always handy to have someone watch your expansion tank when doing this though otherwise you could get wet, as soon as water appears in the tank shut it off and switch on the supply to the float vale to get it to level. Bleed rads and you may need to balance your rads which is in the FAQ

 

[AndyBill]

thanks ,
its a combi system,

so you dont think it will be a problem draining the system thru micro bore?

 

[wonderb0y]

No draining shouldn't be a problem, just find the drain tap, connect a hose to it and empty it, make sure your heating is switched off first though

then just re-fill using the filling loop back to about 1.5 bar but add an inhibitor first as mentioned before.

 

[AndyBill]

how do you get the inhibitor in?

 

[Redhotferrari]

You need to buy a 'tube' of inhibitor, bit like a silcone sealant tube, remove a leed screw off one radiator and use the hose connector and pump the inhibitor the radiator, replace bleed screw and refill system.