Draing the CH system and adding inhibitor

[stevie12345]

Hi just a quick couple of questions.

I'm looking to add inhibitor to my CH system as it was partially drained a couple of weeks ago and i was told that i should add some.

Do i need to add the same brand of inhibitor as before, as this is a house that we moved into 4 years ago and i have no idea what was added before?

Also is this the right way of doing it:

1) Hook up ball valve in F&E tank to stop it dropping
2) Put a hose on downstairs radiator
3) Drain out enough water to allow no water in the F&E tank
4) Clean out F&E tank
5) Pour inhibitor into F&E tank
6) Drain more water from the downstairs radiator to allow the inhibitor into the system
7) Fill the F&E tank up
) Bleed the radiators

Does that sound ok?

Thanks

 

[echoes]

That sounds right.

Careful not to let any muck into the system if you clean the F&E tank. If it's very dirty & brown, there may be a sludge-causing problem, or it may just be many many years of gradual build up. If the CH is fine and all rads get hot all over, then it's an indication of a well-working system.

If the water you drain of is very black or brown, then a dose of sludge remover may be in order. Hopefully neither.

When refilling the tank, check that the feed pipe near the bottom of the tank is covered by just a couple of inches of water when cold.

If you don't know what inhibitor is in there, you won't knowingly be able to add the same type. Sentinel X100 and Fernox F1 are decent brands.

 

[D_Hailsham]

Also is this the right way of doing it:

1. Hook up ball valve in F&E tank to stop it dropping
2. Put a hose on downstairs radiator
3. Drain out enough water to allow no water in the F&E tank
4. Clean out F&E tank
5. Pour inhibitor into F&E tank
6. Drain more water from the downstairs radiator to allow the inhibitor into the system
7. Fill the F&E tank up
8. Bleed the radiators

There is a danger that any muck in the F&E tank will enter the system and cause a blockage; also, air could enter the system.

This way is better:

1. Put a hose on downstairs radiator
2. Hook up ball valve in F&E tank to stop it dropping
3. Empty the F&E tank by bailing it out using a jug etc and a bucket.
4. Remove the remaining water and any muck with old rags etc until the tank is clean
5. Release ball valve
6. Fill to about one inch above the bottom outlet
7. Hook up ball valve
8. Add the inhibitor
9. Release ball valve
10. Fill to normal level
11. Tie up ball valve
12. Drain out, via hose, enough water until level is one inch above the bottom outlet
13. Release ball valve
14. Bleed the radiators (downstairs first).

While you are doing this it might be worth checking that the water level is correct in the F&E tank.

It does not need to be more than a few inches above the bottom outlet. However make sure that the valve opens before the water level goes below the bottom outlet. This prevents air entering the system accidentally.

Check the level before adding the inhibitor! The changes to the steps are as follows:

1-4. As Above
5a. Release valve and fill tank
5b. Drain water via hose until the ball valve opens or the level is just above the lower opening (you don't want air entering the system)
5c. Make a note of the water level and adjust valve arm up or down

(Repeat 5a-c until the valve opens when the water level is about one inch above the bottom outlet)

6-14. As above
etc.

 

[gas112]

Do you have a towel rad , empty that and then take plug out of the top and pour straight in