Are my TRVs cr*p?

We have an "Affordable Warmth" scheme here in NI whereby councils will pay to improve the heating/insulation in your house if you're on a low income.

So when I bought the house 6 years ago, they paid a contractor to put 12" insulation in the attic, replace some blown double glazing panels etc.

Part of the deal was that they'd also replace all 15 TRVs.

They don't work terribly well - turning them up or down doesn't make as much difference as you'd expect, if at all.

More worryingly, recently two of them have started leaking.

So... (deep intake of breath at the thought of the expense) if I'm going to have to get a plumber to replace two of them, would it be better to bite the bullet and get him to replace the lot?

This is the type they fitted - are they crap, or have I just been unlucky?
Any recommendations for better ones which won't completely bankrupt me?

Thanks all

PS don't know if it's relevant, but as far as know neither of the leaking valves have ever been adjusted - the under-specified boiler in the house isn't brilliant at keeping us warm, so they've always been up full...

Where exactly is the leak coming from ? Is it where the pipe enters the bottom of the valve ,or somewhere else entirely ?
I don't know how good ,or poor, that brand of TRV is ,but if you mostly have them fully open and you are not kept warm ,it's more likely a boiler issue ,not the TRV.

terryplumb said:

Where exactly is the leak coming from ? Is it where the pipe enters the bottom of the valve ,or somewhere else entirely ?
I don't know how good ,or poor, that brand of TRV is ,but if you mostly have them fully open and you are not kept warm ,it's more likely a boiler issue ,not the TRV.

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I haven't looked at the one in the hall yet, but a guy from a local firm who services boilers was round a month or so ago, and he pulled the top off the one in the bathroom - pretty sure he said it was leaking from the actual valve (internally). He only does boilers, so wasn't willing to look at it as a job unfortunately.

Oh the rads get hot OK - just takes a long time to warm the house. Two different guys servicing the boiler said it was simply too small for this large bungalow, but it gets there in the end.

Roger465 said:

This is the type they fitted - are they crap, or have I just been unlucky?

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Those are Pegler valves, decent brand.

Roger465 said:

They don't work terribly well - turning them up or down doesn't make as much difference as you'd expect, if at all.

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Are you familiar with how TRV's actually work? They limit the room temperature, rather than set the room temperature. Your room stat, combined with the boiler output/flow temperature might also be set too low.

Harry Bloomfield said:

Are you familiar with how TRV's actually work? They limit the room temperature, rather than set the room temperature. Your room stat, combined with the boiler output/flow temperature might also be set too low.

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Yeah, I know. It's hard to explain what I mean, but I've fiddled with (eg) the two in the conservatory quite a bit to try and get the temp right for the plants, but even on the "frost" setting, the rads seem to be red hot most of the time, though the electronic temperature/humidity gauge in the room (and my skin!) tell me that it's quite warm in there

Anyway, that's not the big problem... if I can manage to get a plumber out to replace these two valves, will he have to drain the whole system (16 rads)?

And I wonder about another thing (probably silly) - you might remember a few weeks ago, on your good advice, I fixed a 6-year problem whereby I was having to constantly bleed the empty kitchen rad, by the simple expedient of turning the pump down to its lower level.

As I'd had to bleed it dozens of times over the years, I assumed the system was now full of pure water without inhibitor, so got a bottle of Fernox into the rad before bleeding it for the last time. I know with cars, sometimes if you flush the cooling system and it hasn't been done for many years, you can get leaks... is it at all possible that some silt or something was actually sealing these valves, and the Fernox has cleaned it out??

terryplumb said:

Where exactly is the leak coming from ? Is it where the pipe enters the bottom of the valve ,or somewhere else entirely ?

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Well... the bathroom one is definitely leaking from inside the valve, but I'm now pretty sure the hall one is leaking form the joint between the TRV and the rad bit of a coincidence for them to fail in different ways at the same time, but there we are... doesn't make a lot of difference to me, as I can't fix either

Tvr control the flow which in turn controls the amount or water running through radiator. More water through the hotter the radiator.
That's why there is no temperature on them and just a number related to flow.
They don't work that well. Can be trail and error as each room is a different setting to get 20c. Most are either full on or off from what I've seen but worth trying to set correctly.
Also some are easy carriage swap without draining system.

Wayners said:

Tvr control the flow which in turn controls the amount or water running through radiator. More water through the hotter the radiator.

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Not quite how they work, the valve at the other end of the radiator works like that.

TRV's use a wax cartridge, which expand when they heat up, shrink when they cool. That action is used to open and close a valve, which in turn controls the room temperature, or rather it limits the room temperature. The basic mechanical TRV, cannot turn the heating on, or turn it up, only limit it.

Wayners said:

That's why there is no temperature on them and just a number related to flow.

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The numbers are because they are not precise, they are a rough indication. Setting is a matter of trial and error.

I have replaced the heads, not whole TRV, just heads, I have used three types, are reasonably cheap, but since Brexit the price has gone up a bit, so £15 each for eQ-3 bluetooth, but can be manually adjusted, uses ºC not silly *123456 as do all three I have used, is programmable, will only work with one phone so either myself or wife has control not both of us, it has window open detect so can shut down automatic for set time while back door is open and emptying car of shopping, like the others powered with 2 x AA batteries, only shows target temperature, single button will toggle between comfort and eco setting.

The Energenie works with PC or Phone, does not allow manual adjustment, needs a hub, has two sensors one for air temp and one for water so compensates for heat from radiator think cost was around £75 a pair, the display shows both current and target so very easy to set lock shield valves, the battery cover is easy damaged and the collar holding the screw tread to hold into the TRV is easy broken and one needs to use a spacing piece to match to some bases, the geofencing using IFTTT and like others is programmable, but the anti-hysteresis software is OTT so would set to 22ºC at 7 am then 20ºC at 8 am to get around the software.

The Kasa (TP-Link) best of the three used but most expensive at £35 it needs a hub, and like the eQ-3 auto sets its self up for how far it needs to move, also like the eQ-e has a kit of parts to fit a selection of TRV bases, can be manually set, and the software has a report to show how heating is working and does show target and current to help set up lock shield valves, it needs a hub, with like the Energenie can also work other things, most non mains smart devices need a hub as to connect direct to a router uses too much power, however this one simply plugs into mains, the Energenie one needs to be hard wired to router.

I would suggest you also look at the Terrier i30 head also electronic and cheap, but never tried one.

With a TRV head which shows current and target one can reduce to lock shield valve setting until the current never exceeds target, and the Energenie in my mothers house once set were spot on, this house the boiler is not a modulating type it is oil, so there is a sine wave where the boiler is turning on/off as well as the TRV head.

When we sold my mothers house, having already set the lock shield valves, when refitting the mechanical TRV heads they also worked A1, but to set using *123456 is near impossible as you are trying to work out both the TRV and lock shield setting at the same time.

Using a mechanical TRV and head and blowing through it to test, in this room starts closing at around 3.5 and fully closed at 2, so where it needs to be depends on size of radiator and size of room. The bees knees is when the wall thermostat and TRV are linked as with Tado, Ecohome, Hive, and Wiser, I am still doing it on the cheap.

Harry Bloomfield said:

.
Not quite how they work, the valve at the other end of the radiator works like that.

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Both ends of the radiator do exactly the same thing. In combination, they provide a resistance to water flow, up to a maximum set by the fixed end.