Radiators Cold in Back Half of Bungalow

[Matwek]

Hi, I'm looking for some advice on my heating.

We live in a 3 bedroom bungalow with the main two bedrooms at the back of the house.
All the radiators in the rooms at the front of the house seem to work fine but as you travel back into the house they get colder and colder, until you reach the back room where they're barely on at all.

Having done my own bit of research it seemed like the problem could be solved by taking a look at the Lock Shield and attempting to rebalance the system.
But after taking a closer look at my radiators I couldn't find anything resembling a Lock Shield.
I've attached an image of both ends of the radiator...

Side Note: I did take a look under to temp control to see if that had got stuck but that was working fine.

Any advice would be greatly appreciated.

 

[SimonG]

2nd photo is lockshield. Look for croppies balancing thread.

 

[Matwek]

Brilliant, thanks.
I did think it might have been but it looked different to every other one I came across online.

 

[townfanjon]

If this has just happened i.e . It was ok last year, its got nothing to do with balancing, I would look more at the pump or a blockage

 

[Matwek]

We moved in a couple of months ago and its been an issue since day one. Only just got round to sorting the issue.

The house had been left vacant for a good few months before we purchased the property though.

 

[Rob Foster]

2nd photo is lockshield. Look for croppies balancing thread.

You could also take off the trv heads and let the heat in properly...trv are rubbish intermediate tech. Fail,often
Are expensive and only sold by installers and merchants to make more profit . A properly
Balanced heating system will be way better and more efficient

Centralheatking

 

[townfanjon]

We moved in a couple of months ago and its been an issue since day one. Only just got round to sorting the issue.

The house had been left vacant for a good few months before we purchased the property though.

So you have inherited the problem , great , not !!
Try turning off the rads that work and see if the other rads that dont , warm up .
As for the comment above about TRV’s please just ignore it .

 

[Rob Foster]

So you have inherited the problem , great , not !!
Try turning off the rads that work and see if the other rads that dont , warm up .
As for the comment above about TRV’s please just ignore it .

Ok we will agree to,differ my friend ...it’s a technical and commercial,matter and I like this engineer ..trv are rubbish !

 

[Matwek]

Thanks. I'll try that.
By turning them off do you mean with the TRVs or via the lockshield?
If I need to shut the lockshield off I assume I need to turn this part at the top?

 

[townfanjon]

Thanks. I'll try that.
By turning them off do you mean with the TRVs or via the lockshield?
If I need to shut the lockshield off I assume I need to turn this part at the top?

View attachment 36015

No just trvs don't touch lockshields , also take off the trvs ( for the moment) in the rooms that dont heat . Carefully push the pins under the trys to check they arent seized.

 

[fronty]

Something else you can try if none of that makes any difference is checking if you have a multi-speed pump, it might just be that the hot water isn't reaching those rads. Does the pipework warm up?

If it's an old system the pump might have a manual lever (marked I, II, & III), you can try it on the next fastest speed and see if that helps, feel free to post a pic here if you're not sure.

 

[Matwek]

Sorry for the slow reply to this advice, bit busy around this time of year.

@townfanjon - I tried turning off the radiators that worked and it didn't make a difference to the ones that were cold.
I also took a look under the TRVs and the pins were moving in and out fine.

@fronty - The pipe work in gets about as warm as the radiators themselves. So a little warm to the touch but not putting out enough heat to warm a room.
Pipes out are cold.
I don't know much about pumps so I've attached an image of whats going on, hopefully you can point me in the right direction.

 

[AMGasServices]

Have you tried to bleed all the radiators ?

 

[fronty]

Ok a few ideas, try each in turn, I'm not an expert so happy for one of the pros to jump in here and correct me, I'm just trying to help:

1) Open all TRVs
2) Bleed all rads
3) Open lockshields on the cold rads, if they warm up then start closing them until you get an 10-20 degree drop across the rad - this takes time, you can't rush it. If this works, then check the remaining rads for similar differential - tighten lockshield to increase differential, open lockshield to reduce it, do it 1/8th turn at a time, wait 10 mins between each adjustment. Aim to get the return temp around 55 degrees
4) If that doesn't work, trying increase the pump speed (if it's an integral pump then not sure if you can adjust it)
5) Try increasing the heating temp, in your pic the dial is on position 4, is that the heating temp or hot water temp? If heating temp then turn it up to max. I've had to run my boiler at max in several houses I've occupied now just to get some decent heat into the rads.

If none of this works then you have a blockage somewhere or the pump is buggered.

 

[Matwek]

Thanks. I'll give that a try over christmas and see how it goes.
Any advice on how to turn the lockshields? When I've looked into doing it they always had a tab at the top to grip and turn with pliers. Is it alright to just grip the side and give it a turn, they seemed pretty stiff so didn't want to yanks something and break it.

 

[fronty]

Turn the spigot (the bit you circled in your pic) either with a small spanner, or just use a pair of pliers, they should turn quite easily, if they don't then use a spanner else the pliers will chew up the spigot.

 

[Matwek]

thanks

 

[Ric2013]

You could also take off the trv heads and let the heat in properly...trv are rubbish intermediate tech. Fail,often
Are expensive and only sold by installers and merchants to make more profit . A properly
Balanced heating system will be way better and more efficient

Centralheatking

I see no need for a TRV/ balancing dichotomy. You can have both.

I agree that TRVs are a fairly poor way of doing things too and would love to have zone valves and room stats in each room but it's out of most people's budget.

A properly balanced system with TRVs added to it is better than a properly balanced system without TRVs though; while TRVs do fail, I have a customer with 13 Giacomini TRVs from what look like the early 90s and last year I only had to replace 3 or 4 of them as the others still work well.

Since the OP is not a heating installer and unlikely to have the skills to be able to rig up a whole new system, I don't see that removing the TRV heads is a solution really. Having said all that, it is possible that the TRVs are stuck and that that is a cause of the problem.