How to drain a Conti NL compact?

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by Ducasd1 »

Can anyone help draining this boiler?
I see the drain valve but it goes with pipe into a junction of main supply


Ps. What will happen if I turn it all the way? It goes out?


#2: Post by Giampiero »

IMO, if the valve at the bottom of the boiler is connected "only" with the OPV of the water manifold....something is wrong there.
Check better to see if the silicone pipe is eventually connected with a T junction and then connected with the drain pan.

Ducasd1 (original poster)

#3: Post by Ducasd1 (original poster) »

Well.. originally I got the machine like that.
The silicone goes out from drain valve to the junction down (see yellow arrows).

The green arrow shows open spot for pipe3/8
The purple arrow shows a tap exactly in the middle.

Is there a way to open the drain valve,
Change the direction of flow in the T junction
& maybe connect another pipe to take all water out?!

Ducasd1 (original poster)

#4: Post by Ducasd1 (original poster) »

My mistake I looked now again from down.
Silicone pipe goes from drain valve to the drain and not down to this main junction.

So if I will open it water should go down
I'm assuming.

Ducasd1 (original poster)

#5: Post by Ducasd1 (original poster) »

I opened the drain valve to max
Even took it out
No water came out...

Does it mean the boiler tank is empty?!

Does a machine like that flushes itself ?!

I'm asking all the questions because I need to replace the heating element and want to be sure it's safe to open this part in boiler.


Team HB

#6: Post by JRising »

Ducasd1 wrote: No water came out...
Does it mean the boiler tank is empty?!
No. Unfortunately it means that the bottom of the boiler is so heavily laden with mineral deposits that nothing flows through to escape by way of the drain valve. The drain valve might be hard to remove without breaking, if the mineral deposits are too solid. You might be better off siphoning the boiler dry through either the safety valve's or the vacuum breaker's ports.

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#7: Post by stuartmac »

i have a fleet of conti stuff, yes that's the drain and you did it right, normally you just crack that open a few turns.

Most likely clogged as stated so looks like your doing a full teardown. pull the safety valve or vacuum breaker out and just flip it upside down outside in your lawn to drain out.

looking at the scale i would say the HX injectors are probably quite bad as well.