Refilling closed CH system

irlrobins

Not going to lie, I've haven't a notion when it comes to plumbing/heating so forgive me if this is a stupid question.

My gas CH is a closed system with a Zeus Maior boiler (Manual)

I need to bleed one of my rads which will lead to drop in system pressure. I know i need to increase the pressure by filling the system with more water to bring pressure up to 1 - 1.2 bar.

My query is do I need to connect a hose to a valve on the boiler to do this? Or is the boliler plumbed to the mains so can I just open and close a stopcock to fill with water? How can I tell which approach do I need to take?

Thanks!
R

heinbloed

Better get a real serviceman/plumber in.
Bleeding 1 radiator won't do the trick, do them all, the entire system has to be bled.
After that the expansion barrel has to be checked for adequate pressure (1-1.2 bar in case you run your boiler at this pressure). The anual maintenance has to be done and protocolled.

The central heating part of the boiler should never be permanently connected to the main water pipe.
Only temporary when filling/topping up the pressure.

So if you boiler was installed correctly there won't be a possibility to

just open and close a stopcock to fill with water

.

The filling loop must be connected before filling and disconnected after filling.

irlrobins

Yeah I thought that might be the case. Better start looking up the goldenpages I guess!

Thanks.

crosstownk

The chances are you have a filling loop installed with a valve which is normally closed. The location of this valve varies depending on your central heating layout and the installers preference.

Have a look in the usual places, hot press, attic, near the boiler, etc. You won't have too many valves that are closed so it should be easy enough to find. It may be a regular pipe valve or it could be a tap on a braided hose that only turns through 90 degrees.

Once you locate the valve it's simple as long as you can read a gauge and turn a valve on and off - very DIY and certainly no need to call a plumber.

irlrobins

Well if it's going to be anywhere it will be in my apt's utility room. I've attached some pics of the pipework going to and from the boiler (combi with internal tank, no tank elsewhere) in case that helps.

Buford T Justice

You're filling valve is open, and it shouldn't be under normal circumstances.

Bleed the rads, and the pressure will top up automatically. Once you've done this, and the system is topped up, turn off the valve under the boiler. The red valve.

irlrobins

Red valve shuts the water to the apt from the mains. i.e if I close that, no water.

Jedstaff

The black round knob in pic3 looks like the filler valve to me.

crosstownk

Read section 2.5 on page 19 of the manual you linked to - that may help you.

While I'm not 100% sure, it would appear that your boiler stores domestic hot water and is mains fed. The red lever will shut down water supply but there is a second valve (sec 2.5 p19) that allows system pressure to be topped up. Your domestic hot water is fed from the mains into a 60 litre tank in the boiler unit. It's heated and stored there as required.

irlrobins

Opening the black knob (filler cock) seems to have done the trick. Upped the system pressure, bled rads then upped pressure again. Just firing up the heating now to see if the whole rad now heats up.

Cheers guys.

R

crosstownk

Sounds like you're sorted!

Sparkpea

yes the black knob seems to be the key allowing the system to fill, from what I've seen some worchester boilers have this and from what I read, the key shouldn't be left in the boiler for safety reasons, but dont loose it!

irlrobins

Not sure if mine is removable or not. Either way, it's not doing any harm where it is so it's staying right there!