Multiple drain points

[Redhotferrari]

Hi Guys,

Need to replace a radiator on the ground floor. All rads on the ground floor have drain points. Am I right in thinking that by using the drain point on the rad I am changing will mean that I do not have to drain the whole house down?

Will the flow and return to that rad clear without doing all the ground floor rads?

Running on a combi boiler, so can not bung the F&E.

Many thanks

 

[JohnD]

If you have a sealed system, it is effectively bunged. If you open the drain on that rad until water stops coming out, then close both rad valves, you can swap the rad. Don't have two points open at the same time.

Put a shallow bowl or a emulsion roller tray under the valve when you start to loosen the rad nuts. Open just one end first, and open the bleed valve to let the rad empty.

When you lift the rad off:
1) tip it into a bucket

2) turn it upside down so water and sediment will not dribble out while you are carrying it.

Observe what tips out to see how dirty the water is and if you have black or brown sediment.

 

[Redhotferrari]

Only problem there is and should have said earlier, I will be moving the radiator about 6 feet to the right on the same wall, so will need to alter pipework.

 

[JohnD]

after you have released the pressure as described above, open ONE rad valve and whiz through its pipe with your pipeslice (or take the valve off if you are going to connnect in the same place). Have your new elbow (with a stop end) or isolating valve or whatever ready to put on. Some water will fall out but not very much.

Do not cut the second pipe until you have sealed the first.

Be aware that you cannot solder a wet pipe.

 

[seco services]

why do people always say only have one pipe open on on bung system when it's not true as you can change almost anything on bungs, eg pumps, radiator pipework, 3 port valves ?

 

[namsag]

Your nearly right Johnd but if the boiler cannot be isolated with the appliance isolating valves any auto air vent must be closed off ie cap screwed down. otherwise air can enter breaking vacum

And as seco says one pipe open is not correct think about it a cutting into pipe is exactly same as removing a rad completly it is one break in circuit the reason for shutting one valve at a time is just in case something happens.

And also can change about 85% of 3 port valves no problem with 3 open pipes and 2 circuits

 

[nickso]

why do people always say only have one pipe open on on bung system when it's not true as you can change almost anything on bungs, eg pumps, radiator pipework, 3 port valves ?

agreed. at worst you only have to wait a bit longer for the vacuum to hold.

 

[Redhotferrari]

Do not really like to use compression joints or iso valves to a rad as think they look awful, especially as this rad is very much the center of the room...

Soldering will be the way for this one, thats why I was asking about draining.

 

[namsag]

soldering is not a problem on vacum but best to drain as a diyer