Radiator connections

[dd2005]

After a cold downstairs over the last few weeks I have embarked on sorting out the heating system in our house (moved in during the summer)!

I intend to install TRV's, but our downstairs radiators have drain plugs between the inlet valve and the radiators which have large screw thread fittings which are bigger than those on new TRV's.

My questions are:

1) Is the fixing into the main radiator a standard size, i.e. if I remove the drain plug fitting can I install a new drain plug and trv, or will I find the connection into the radiator is also a different/old size.

2) Can I use a reducer to allow me to use the old drain plug with a new trv?

3) Do I just remove the old radiators (1980's) and replace with all new fittings as the connections may look like a dogs dinner if I use reducers etc! There are only 3 as some radiators are getting replaced in new locations.

4) I have the same thread size issue upstairs, but without the drain plugs, can I remove the valve and threaded part into the radiator and replace this with one from a new trv or will the thread/size be different?

Any help greatfully received, will add a photo once I can get it off my phone!

Thanks

 

[plumbnuts]

1) Is the fixing into the main radiator a standard size, i.e. if I remove the drain plug fitting can I install a new drain plug and trv, or will I find the connection into the radiator is also a different/old size.

The thread size is normaly 1/2" BSPT and I assume you refer to valves with a built in drain cock. You will need a special allen key (Available from plumbers merchants) to remove the old valve and a spanner to tighten the new TRV. You will need to fit an auxilary drain cock assuming that the radiators are on drops.

2) Can I use a reducer to allow me to use the old drain plug with a new trv?

N/A

3) Do I just remove the old radiators (1980's) and replace with all new fittings as the connections may look like a dogs dinner if I use reducers etc! There are only 3 as some radiators are getting replaced in new locations.

Don't waste your money if the rads are in good condition.

4) I have the same thread size issue upstairs, but without the drain plugs, can I remove the valve and threaded part into the radiator and replace this with one from a new trv or will the thread/size be different?

These can be changed as above without the need for the drain cock.