Central heating woes

[twodoctors]

So we had a new combi boiler installed. Worcester Life 8000 35kw (so a half decent one then). The installer did a flush of the system and 2 of our radiators are leaking. One of the lockshield valve is a bit leaky also. I was going to get my usual plumber to sort it out but after a few no show he's been "sacked". I was contemplating doing it myself, bought all the stuff, watched the YouTube tutorials, but now having second thoughts!

I have been quoted around £350 to £400 to replace 2 radiators and valves. Sounds a lot of money to me to be honest. Is that roughly how much I should expect to pay?

I was trying to balance my radiators also, and I think I've got it. However 1 of my radiator, with a Drayton TRV4 valve, now refuse to come on. There is no air lock (tried bleeding it), the pins on the valves are free and easy to depress. The only thing I can think of is incorrect balancing of the other radiators (or even knackered valves). Do I turn all the other radiators off and see if this comes back to life (and therfore balancing issue) or is there something else I should check?

Thanks.

 

[CBW]

Price wise - seems a lot imo, as presumably you already have the stuff? I’m not self employed, so I’m not in touch with how much jobs should cost.

 

[Harry Bloomfield]

I was trying to balance my radiators also, and I think I've got it. However 1 of my radiator, with a Drayton TRV4 valve, now refuse to come on.

Try turning off all of the other radiators, via the valve you didn't set for balance/ or TRV - so maximum flow goes to that problem radiator.

It could be poor balancing, an air-lock, or a blockage. Report back with the result.

 

[oilhead]

For a days work , draining down, fitting and refilling, the quote is not unreasonable particularly as £70+ will be vat. You will also expect him to ensure the system works upon completion of the job.

 

[gas112]

is that price purely labour or does it include the rads also what size rads

 

[twodoctors]

is that price purely labour or does it include the rads also what size rads

Purely labour. Rads are 600 x 600 and a 900 x 600 ish.

 

[gas112]

Purely labour. Rads are 600 x 600 and a 900 x 600 ish.

same size as existing ones with no alteration even minimal alteration ? then that price is certainly on the high side

 

[twodoctors]

That's what I thought also. I was thinking maybe £100 per radiator would be fair... At £350 I'm considering doing it myself.

 

[Harry Bloomfield]

That's what I thought also. I was thinking maybe £100 per radiator would be fair... At £350 I'm considering doing it myself.

It is not a difficult job, just very basic DIY, just make sure you use inhibitor afterwards, to protect the system.

 

[twodoctors]

I think I will have to do it myself...

So do I drain the system from here?

And then change the radiators right? I have a combi boiler. Where do I pour the inhibitor in? This is my boiler.

Thanks all.

 

[Harry Bloomfield]

Yes, that is a drain point. Just fit a hose tightly, leading to a drain and open the valve, with a spanner. Turn the heating off first, and then when the flow slows/stops, open bleed valve(s) to let air in.

Have plenty of old towels to hand and once that rad is drained - tighten the bleed valve, undo the unions, lift the rad off the brackets and flip it top to bottom, to avoid further draining as you carry it out.

 

[gas112]

in reality you do not need to drain it isolate the boiler with the valves underneath (new boiler so valves wont leak)
drop the pressure by letting water out of one of the bleed screws or cracking the union on the valve you will get a pint or so of water come out before it air locks up then you can change then valves no problem

 

[twodoctors]

Just to be clear, that drain point is not the radiator I'm swapping. It's on the downstairs radiator, and presumably I can drain the system from there.

I know how to top up tht system (with a switch under the boiler). Where you I put the inhibitor in? Somewhere on the magna filter?

But as gas112 mentioned. A lot of videos says I don't necessarily need to drain the system to change the valves unless i misunderstood them.

(that's why I was going to let someone else do it, but at £350 I think I'll have to have a go myself!)

 

[terryplumb]

Where are the two radiators that you intend to replace ,are they upstairs ?
Is it a third radiator that doesn't heat up ? If so which floor is that on ?
Unless your new radiators are exactly the same as the ones you intend to replace ,your pipework may not line up and may need slightly altering.

 

[Harry Bloomfield]

Just to be clear, that drain point is not the radiator I'm swapping. It's on the downstairs radiator, and presumably I can drain the system from there.

You only need to drain the water down to a point below any part you will be undoing/taking out.

Where you I put the inhibitor in? Somewhere on the magna filter?

You can put it into the system anywhere at all, it will circulate around. Once you have the rads in, if you are satisfied you have no leaks, pour the inhibitor in via the bleed plug at the top.

But as gas112 mentioned. A lot of videos says I don't necessarily need to drain the system to change the valves unless i misunderstood them.

It can be done, but there is a risk. Safer, easier for a novice to just accept the need to drain.