2 Problems! Related or just unlucky?

[Jimbobc]

Hi all,
I'll be brief but try to include as much info as poss.
Problem 1 - Last Winter I noticed that the top half or 2/3 of all the upstairs radiators were cold - I can take the bleed valves off, go and make a casserole and when I come back still no air escaping!
So I was thinking of flushing the system with X400 or similar, then...

Problem 2 - A couple of weeks ago after a very cold shower I realised the hot water wasn't working - the motorised valve doesn't open. I replaced the motor and still nothing, I can open it manually to operate the CH.

My question is; are these two related, is my system just full of gunk that needs flushing out.
I've already paid for the new motor about £15 but I don't want to start buying flushing agents and inhibitors if the problem is something else.
Open system with header tank, boiler from the early 70's.

Help or advice on fault finding would be much appreciated.

 

[Scottley]

When you say you can open the bleed valve but no air is escaping im guessing there is not water either, the system must be empty.

Is there water in the header tank? It could be the pipe that feeds the system from the tank is blocked.

 

[Jimbobc]

Hi Scottley,

Thanks for replying. Just a little hiss of foul air escapes, then nothing. No water or air. I will look in the header tank when I get home, just wanted to know what I'm looking for. Presumably if there is water in the tank then a blockage to or in the pipe, and if no water in the header tank then a more serious problem unless the ball valve isn't working. It's a tiny loft and I'm not tiny so look thoroughly, look once will be my aim.
Can the two problems be related - I don't know if CH & HW use separate pipes?

 

[Scottley]

From what i know (which isnt a great deal) if the water level drops far enough in the system it wont work.

It could be as simple as the ball valve stuck up in that air.

 

[Puddle]

As scottley says,first check header tank is not dry/no water in it,it could be ball valve stuck up or maybe someone has turned isolation valve off to tank as a quik fix to stop over flowing

It does sound as you need to get the system full of water again

The hot water and heating pipes are separate and there could be a fault with the valve/s but first things first,get water back in system and go from there

make sure system is turned off when you vent rads as pump can suck air into system when venting rads on some older set ups

If tank full of water,probable blockage in cold feed
what boiler do you have ?

 

[Jimbobc]

You know more than me Scottley. My old combi boiler in my old house used to work with or without water - an amazing knocking sound that makes you sprint for the off switch.
Thanks also Puddle - I will go into the loft and try and get some water circulating again, I didn't know that about the pump sucking in air on loder systems (Potteton Kingfisher looks to be 30 years old at least), so I will turn that off first.
Thanks for all your help and ideas, much appreciated.

 

[Scottley]

These are all problems i have encountered fitting bathrooms the last few years. Didnt have forums for help then!

 

[Centralheatking]

Get some water in the system then see what happens.

Shoot it up with mains pressure water - connect the drain off point via a hose with a jubilee clip on it to the mains water supply in the same manner. Open the drain off and turn on water, wizz around the rads and air will rocket out, too much mains water and the tank will overflow so do it in stages.

No air locks anymore simplze !

Then flush through with mains awter and see how much magnetite sludge comes out and then refill. Wack in some chemicals later.

centralheatking

 

[ferret]

I use a simpler method 2xflexi tap conns joined together with a 22mmx15mm comp coupling on the end , connect in place of ballvalve and use 22mm comp to open vent , blast mains down o/v untill it clears the cold feed back into tank , easy and nothing else to worry about cos your in loft with it.

 

[WaterTight]

I like that. As long as there are no impending criticisms or better ideas I'm going to rig myself up one of those.

 

[diesel_ltd]

have you tested your room stat? if you have a faulty room stat it will not turn over the motorized valve and fire the heating......

when your bleeding the rads make sure the heating motorised valve is open, when doing this you dont want your pump running. have you checked to see if the vent in the rad is blocked use a pin to see if theres any dirt in the vent.

be careful when taking the vent out of the rad as you could get a bit of water if it is blocked and it can be hard to get the vent back in when the water is gushing out

 

[Blackcatgas]

Blocked cold feed? is it fitted with a myson airjec? I mean myson sludge catcher.

 

[turnpin]

all good advice here once again ..just wondered any thermostatic valves on the rads if so pins may be stuckregards turnpin

 

[Centralheatking]

Nice one ferret ! I will get one made up aswell it makes much more sense than the other way I use.

centralheatking

 

[jammydodger]

i like that idea. i jus do it live by creating a vacuum on the tank, then i relace cut out blockage section usin 2 comp couplers so i can easily take them apart next time they call.

 

[Jimbobc]

Problem 1 - No hot water - Solved.
Thanks Scottley & Puddle, you were both right. I looked in the loft and some clumsy oaf had knocked the lagging into the expansion tank when putting the Xmas decs away - I guess that was me!
The ball valve was stuck up and the expansion tank was completely dry.
Removed the lagging, released the ball valve and lovely water filled the tank and a pipe that went down to the boiler. 5 minutes later and after lots of gurgling noises hot water throughout the house!
Lots of good ideas for the radiator problem - I will tackle that later as my Wife is happy with the HW being fixed for now.
Thanks all.

 

[Scottley]

Excellent!

 

[diesel_ltd]

good to see you got a result now you need to put a tank lid and jacket on that F&E tank to stop this happening again

materials needed;

F&E tank lid
F&E jacket

should be less than a £10 in a plumbing suppliers, think of the call out fee you saved on this site and use it to buy these materials

 

[Scottley]

good to see you got a result now you need to put a tank lid and jacket on that F&E tank to stop this happening again

materials needed;

F&E tank lid
F&E jacket

should be less than a £10 in a plumbing suppliers, think of the call out fee you saved on this site and use it to buy these materials

Good point there i reckon

 

[kay-jay]

nice tip about rigging up a couple of flexi's ferret!

do you use it just for blowing airlocks out of heating system and/or blockages??

also,

could this be used on the hot water side in the f+e tank for cylinder if a blockage or airlock is suspected or am i missing something painfully obvious??

thanks

KJ