Replacing entire filling loop on Vaillant EcoTec Pro 28

[Plantman2000]

Hi all, I think has been discussed before but I don't think I've seen a clear answer. We have the Vaillant boiler as above and the filling loop has started to leak from around the olive joint on the cold water side.

I would like to replace the whole loop, flexi, taps and the valves etc.

I can turn the cold water main off with no problems but my question is, would removing the central heating return side end up draining all the upstairs radiators by removing this valve please?

I can turn off the valve between the TF1 and up to the boiler and I presume the Vaillant has a valve/solenoid to prevent water draining from the boiler down (mains water would be off at stopcock) but would the rads water pressure push water out on that side?

I guess i could just replace the leaking cold water check valve side and leave the rad valve side in place but would like to replace all if poss.

I attach some pictures.

Many thanks!

 

[Deleted member 120897]

If you turn off the the valve above for the fernox omega, then you’ll get a little bit out, but if you keep the loop on that side, disconnect the water side, then you have a makeshift drain hose, place hose into a suitable container and open the heating side, continue with replacement after water has stopped. You shouldn’t get that much.

 

[Plantman2000]

Thanks, we have 4 rads upstairs, would they end up draining through this? How quick would the flow be?

I guess since I am keeping the olives and original nuts in place when I replace the loop I could just be quick to screw the new valve on to the rad return side.

Do you recommend and PTFE as well at the olive side considering they are originals?

Cheers,
Chris

 

[Deleted member 120897]

Hi Chris,

No it shouldn’t drain upstairs rads. If you use the flexi as I’ve said, you can control the flow, although it shouldn’t be all that much. Yes, re-use of olives will be a case of unscrew and screw new ones on. Ptfe is a preference, but since you want to get it right, it’ll do no harm, just don’t put any on the threads - it’ll look naff and do nothing 😂

Also Chris.

 

[ShaunCorbs]

Tbh

Loosen the heating side valve enough so you can undo the rest by hand be careful you don’t undo it all the way yet

remove the flexi cold water side and insert into a bucket open the valve

Have the other valve on hand

Wait until you see the pressure drop close the valve undo the nut fully

Then open the valve into the bucket again and quickly pull the old one off and put the new one on

Tighten up and your done the heating side

 

[Plantman2000]

Hi Chris,

No it shouldn’t drain upstairs rads. If you use the flexi as I’ve said, you can control the flow, although it shouldn’t be all that much. Yes, re-use of olives will be a case of unscrew and screw new ones on. Ptfe is a preference, but since you want to get it right, it’ll do no harm, just don’t put any on the threads - it’ll look naff and do nothing 😂

Also Chris.

Thanks very much Undertrained 🙂
Appreciate your help.

 

[Plantman2000]

Tbh

Loosen the heating side valve enough so you can undo the rest by hand be careful you don’t undo it all the way yet

remove the flexi cold water side and insert into a bucket open the valve

Have the other valve on hand

Wait until you see the pressure drop close the valve undo the nut fully

Then open the valve into the bucket again and quickly pull the old one off and put the new one on

Tighten up and your done the heating side

Cheers ShaunCorbs. Sounds like we know the recommended procedure then. Many thanks.
Chris

 

[cjg]

looking at that the return pipe in 15mm after filter on way down?

 

[Plantman2000]

looking at that the return pipe in 15mm after filter on way down?

The return pipe with the TF1 is certainly 22mm. Probably looks odd in the picture due to the pipe insulation.