cast iron radiators

[strand]

Hi, I'm hoping for some advice about what problems I might encounter connecting some old (reclaimed but yet untreated) victorian cast iron radiators up to my nearly-new combi-boiler based central heating system.

In particular:

1) I've heard it's advisable to get the radiators acid flushed and pressure tested before I connect them. Is this true, and can anyone suggest a company not too far from the cambridgeshire area?

2) Do they have too high a water capacity, take too long to heat up or make the system too difficult to balance successfully?

3) Can you use inexpensive modern valves (i.e. my existing thermostatic valves) with these old radiators? Is there a supplier of suitable adapters anyone can recommend? Is re-threading the radiators neccessary / a problem?

Any other warnings would be much appreciated!

Cheers.

 

[mngray]

Just bought one myself. The tap holes seem to be the usual 1/2" type, but I cannot unscrew one of the old ones - it seems locked in. Does anyone have any idea how to get it out? Can I apply heat, or is that a waste of time? My rad spanner just bends when I apply too much pressure. The air bleed valve seems to have been reseated, and I can get an M6 screw to thread in (although it seems very slightly loose. What type of valve is this and where can I get one?

Thanks