HELP! My Boiler's stopped after bleeding a rad!

[Jameszee]

Hi everyone,
My first post here and I really have no knowledge of heating systems, so I hope I don't miss any info out that you need! But any suggestions will be appreciated as I’m freezing my knackers off and smell like a horse!

I've a British Gas combi boiler (CDi Series); the previous occupant had the full new system installed in 99, but has left me no manuals for the system!

As described, there was a rad in my system that was nearly completely full of air; so I bled this rad yesterday.
It hissed away nicely and I felt the hot water rising within the rad quite swiftly. When the water level had almost reached the top of the rad, the boiler came on and started circulating and heating the system. After about a min the boiler just stopped and the pilot light went out!?

I tried starting up the boiler again, by holding the ignition button (fully automated ignition, not manual), which did nothing! There was a gentle whirring noise coming from the boiler throughout this time (which was not an unusual sound for it to make under normal circumstances). At this point I noticed that the pressure gauge needle had fallen to zero!

After this I switched off the entire system, and then switched it back on again. I managed to get the boiler fired again where it heated up some tap water; but the system shut it self down and pilot light went out after about 10-20 secs!

I carried on trying to get the pilot light up and running again, but the gentle whirring noise that was happening before had now changed into a loud screeching noise! I've left the system turned off since!

I'm taking a guess that I've let some air into the boiler, and some sort of pump that normally works wet, is now dry hence the screeching and loss of pressure!?

I've contacted British Gas who've said that I can sign up for their service cover, but the monthly cost will be almost double (Which I won't mind paying if necessary!) because of the existing problem + they can't sign me up until tomorrow because they haven't offered this option over the Xmas period (bless em!). Also there is a department that I can contact that can post me a manual for my boiler. (Which I’m not prepared to wait for in the cold!).

Can anyone suggest what my next step should be? Have I made a simple error that can be rectified? Or shall I give BG a call tomorrow to get an expert round to fix the horrendous mess I’ve made of my boiler??

Thanking you for any advice in advance!

James.

 

[oilman]

There are loads of posts which deal with your problem, search this forum for filling loop and expansion vessel, and you will find just about all anyone needs to know.

Good luck.

 

[breezer]

Its nothing to worry about, do a search on these forums, for refilling system, low pressure and empty radiator

you will find the answer

 

[Jameszee]

Thank you very much Oilman & Breezer for your swift replies! With 797 & 2514 posts respectively under your belts, I'd say you'd know what you're talking about!

I'll reply to this post if I have any further probs after searching the site!

Cheers

 

[Jameszee]

I've made alot of progress since my first post!

Problem I have now is that I do not have the filling key!

Does anyone know what i can do??

Thanks

 

[Jameszee]

Okay, I have some pics of the boiler which i tried to attach to the previous post!
But guess what I don't know how to post them!

Basically, I just need this key to fill the system a little!
I'm taking a guess that a Boiler Spares place may stock these??

Any help appreciated!

Cheers.

 

[breezer]

try looking in welcome to the forums, the instructions are there

 

[MANDATE]

I presume by bleeding the radiator you have reduced the pressure to below the set limit of the pressure switch.
You need a flexible filling loop for many combis so the pressure can be increased. In your case it sounds as though the filling loop is a permanent fixture and you just need the valve key to open it.
To describe the key you will need to know if the spindle head is 'square' or 'hexagon' or 'round with machined flats' and of course the size
When you do open the valve for increasing the pressure, only open it a little and observe the pressure rising on the gauge.
If you overdo it and the pressure goes too high there is a pressure relief valve but I believe when it opens and closes when the pressure has reduced it does not always seal correctly giving you another problem, so it is better if you don't reach the opening pressure.
You can usually improvise if you can't get a key, I'm thinking of adjustable spanner, pliers etc but it depends on the shape and the size.

 

[COG]

Contact Worcesters spares department they did send them out free, if not you shoul be able to buy one but make sure you say its for the older model key as they changed the design 9 months ago.
When you re-pressurise your boiler vent the pump from the chrome screw on the face of the pump prior to starting the boiler and make sure the dust cap (if fitted) on the top of the auto air vent is not tight,the auto air vent is pokeing out of the top left of your boiler.ps you do know the filling instructions are on the back of the front panel.

 

[oilman]

Mandate wrote:

If you overdo it and the pressure goes too high there is a pressure relief valve but I believe when it opens and closes when the pressure has reduced it does not always seal correctly giving you another problem, so it is better if you don't reach the opening pressure.

The gas pressure in the expansion vessel should be checked anually, and this should be done with the system pressure at zero. The simplest way to reduce the pressure is to open the pressure relief valve. This also checks the valve is not stuck. These tests are covered in BS7074 part 1. If the valve doesn't seat properly, it is either the valve is faulty, or there is dirt on the seat, in which case the system does not meet the BS 7593 (I think) spec for dirt in the system.


I agree the valve might be a problem, but valves have been known to stick up to 10 bar.