vaillant Thermocompact refilling the system

[kevinon]

Hi out there

Can anyone tell me how to refill the vaillant Thermocompact system in my home? The instructions say to follow the the instructions left by the installer, but of course they didn't leave any (I did'nt think to ask them to when we moved in!) The pressure gauge is at zero. I did bleed a radiator in the bathroom this morning so i'm wondering if that has caused the problem. The system is just over two years old.

Thanks, appreciate any help given.

Kevinon

 

[gas4you]

There should be a filling loop/link somewhere under the boiler probably.

Usually a flexible silver braided pipe with an isolating valve at one/both ends.

Pressurise it to just over 1 Bar cold.

 

[petit_pablo]

Its underneath the boiler either at the back left or front right. I cant remember which it is on this model

 

[kevinon]

There should be a filling loop/link somewhere under the boiler probably.

Usually a flexible silver braided pipe with an isolating valve at one/both ends.

Pressurise it to just over 1 Bar cold.

Hi Dave/Petit_Pablo

The only braided pipe found next to the boiler has no valves either end and I can't see any where it would fit underneath the boiler. However, there is a valve that turns anti-clockwise that appears to open/shut when turned, what does it do? Yep not a plumber as you can see!

Cheers

Kevinon

 

[blondey]

Hi

I'm not a plumber but I have the same boiler make and the same problem! I bled all the radiators this morning and the pressure went to zero and I had no heating although I had hot water. I have refilled the boiler by turning the silver key on the bottom. The filling loop thing should be easy to see- it's silver and has a key type end to it. I have the turbo plus model but it should be essentially the same - it was the only obvious thing to turn when I looked at the bottom of the boiler!

Hope that helps you. I refilled mine to 1 bar and it's now working!

 

[kevinon]

Thanks 'Blondy' but Just spent another 1/2 hour trying locate this 'silver key' thingy, but no joy I definitely do not have one. However, there is a knob with 3 bar written on it, but it does not turn, just clicks ant-clockwise, does anyone know if this the alternative to the silver key folks tell me about and if so how do I turn it? Do I need to turn off the whole boiler if only the water heater is working?

Thanks

kevinon

 

[gas4you]

This 3 bar knob is the pressure relief valve, do not turn this as you may get some muck stuck in it and it will not seal again, making you have a new one.

 

[twgas]

your filling loop may have a screw driver slot instead of a lever.

 

[kevinon]

Hi, thanks to everyone for there help, its was very much appreciated. Unfortunately I am going to have to get a plumber as I have twiddled and turned every screw/nut/bolt with no success and living in Fife my wife and I are freezing our 'extremities' off. Cheers Kevinon.

 

[blondey]

Hi

Right, I'll try and talk you through what's on the bottom of my boiler as I think it may help but the silver key I have comes off so i think you need a "key" to turn the valve- it's a bit like a small radiator key and if you don't have one then try using a screwdriver - it should work and save you a plumber's bill!
If you look at the bottom of the boiler (there may be a plastic grill which you need to take off- it undoes with little plastic knobs) on the right of the boiler at the front there are two valves which protrude. The valve for the cold water mains is the second one in at the front. Use a screwdriver to turn this and you should hear water being let in and the pressure will rise.
Underneath my boiler is a sticker which labels the connections.

Hope this helps!

 

[kevinon]

Hi blondey

Found out that the two pipes everyone told me about are actually several feet from my boiler (I blame the builder!). Started to fill up the tank, but it appears the 3 bar pressure valve (I mention earlier) which feeds the overspill pipe is stuck open as all the water is poring outside onto my path and no pressure is therefore building in the tank. Now not sure if I need a new pressure valve or what? I can't believe bleeding a radiator could be so time consuming and problematic! On the positive side I must say its nice to know that there are people out there who try and help others. Thanks.

Kevinon

 

[twgas]

try turning the "3bar valve" a couple of times to see if it will re-seat, at least enough to fill boiler and get you some heat and water

 

[TBag]

Hi,

I have just joined as you have been discussiong my exact problem. I have a Vaillant Thermocompact which has reduced to 0 Bar pressure. Whenever it starts up there is a banging sound for a few minutes, but this dies away and it does actually work for both heating and hot water, but the noise is clearly not right and I think associated with the zero pressure. I too only have the unhelpful advice from the manual about consulting the non existent installers instructions about how to fill the sysytem. I have looked at the nearest current equivalent manual for the ecoTec Pro which talks about opening the valve on one of the 4 pipes underneath the bolier to let in water. Unfortunately, my boiler only has 3 pipes leading to it. The middle one is the gas pipe and the outer 2 are water, but all 3 already have their vales in the open position. At the far right is the 3 bar pressure relief valve discussed above. I think my system refil must be somewhere else too, but where do I look. I have a utility cupboard that houses the enormous hot water tank with a smaller pressure vessel above it and a mass of piepwork and lever valves that interconnect all this (including a water softener and a large pressure pump to provide high pressure water to all our taps) - it's more complex than the Tornado I fly for a living! So before I do somethging terminal and twiddle the wrong valve, and before I resort to a plumber, can any of you suggest how I might refill the system to get pressure back in to my boiler. I could always take a photo to post if it helps.

Thanks in advance

T-Bag

 

[kevinon]

Hi sorry just picked up email. Firstly, the two pipes i needed to connect to fill the boiler were several feet away from it! There is a braided pipe that fits between them (two pipes have on/off valves). To stop pressure drop I found that there is a 3bar pressure valve thats connected to the over flow pipe and the boiler (bottom right under boiler) that drains off to the outside. This was continually leaking off the pressure from the boiler. Being someone that used to fix Tornados in a former life, I broke it open and tightened the screw inside. Its now working!!!

 

[TBag]

Ah a real 'ginger beer'! Thanks very much - I did actually find the braided hose and valve 2 rooms away! Filled it up no problem and now all is well. Thanks again.

(Hope it was an F3!)