Flow Temperature or Thermostat or TRV or Lockshield Valve?

bery_451

Reed_Richards said:

bery_451 said:  

Ok to confirm in a room where the rad TRV and thermostat wireless control is in the same room, the TRV has higher priority over the thermostat when it comes to air temperature for that room meaning the boiler will constantly use gas not turn off because the thermostat will sense a lower room temp than the set temp on the thermostat?

Yes that is correct.  The boiler will constantly use gas until such time as the return water temperature gets so high that it triggers the boiler to cut out as a safety feature.

bery_451 said:

Can the same be said vice-versa, where the TRV setting is at max 5/6 position but the set temp on thermostat is lower than the TRV 5/6 position meaning it will stop the boiler using gas because room temp will get higher than set thermostat temp?

Yes, that is correct for ordinary TRVs.  If you have programmable TRVs linked to your heating system it could be different.  But you don't have those, do you?

bery_451 said:

So in summary it is better to put your TRV's in max 5/6 position to stop the risk of your boiler overheating and using tons of gas doing so?

Yes, if the TRVs you are referring to are the one/ones in the same room as the room thermostat.  You can set the TRVs in other rooms to whatever setting you like.
  

I don't have the programmable smart TRV's, just the normal standard ones from screwfix.

Are the TRV's in general reliable and how long do they usually last before they need replacing? Are TRV's reliable as in the temp sensor in them doesn't malfunction over time and they give constant accurate readings? Do normal TRV's require calibration every so often to keep its temp sensor accuracy? What if you see like a dirty yellowed out TRV, can the dirt/grease/dust affect the temp sensor in them? Is it possible for normal TRV's to be installed fitted incorrectly? Finally how does a person fully test/diagnose a TRV to check its working as it should as in the corresponding numbers on the TRV senses the right air temperature?

bery_451

Ectophile said:

bery_451 said:

FreeBear said:

bery_451 said: Hi you mean 10kW of Gas being used at the start? Only smart TRV's can turn off radiators individually or any TRV has a built in room air temperature sensor meaning if the room temp is higher than the set TRV temp then the rad will turn off automatically regardless of what is set on the thermostat or where the thermostat is?


What you mean by balanced, Rad is level? How you set the pump speed for each rad?

The graph is from a heat meter that measures the flow rate of the water along with outing & return temperatures. From that, it automagically calculates how much energy is being used to heat the house. So when I say 10kW of heat, this is the amount of energy being produced by the boiler. Not being able to monitor actual gas consumption beyond what the (smart) meter tells me, I can't say what the instantaneous use is - Could fit a lab grade sensor to the gas pipe, but it would probably breach countless regulations and give a Gas Safe engineer a fit if/when I need a safety certificate issued.

A standard (non-smart) TRV reacts to room temperature and will slowly close off the radiator valve. Doesn't need smarts or batteries to do so. To change the temperature at which a radiator turns off just means picking a number (for my TRVs, No.3 is equal to about 19°C).

Balancing the radiators means setting the lockshield valves to get a consistent temperature drop across each radiator (typically, 12-20°C depending on flow temperature). This helps to ensure that each radiator in the house heats up at the same rate and can improve efficiency of the whole system. As part of the process of balancing the radiators, you may need to turn the pump speed down so that the correct temperature drop across each radiator can be achieved without shutting the lockshield right down.

Plenty of guides on the internet on balancing radiators. This one goes quite deep in to the technical aspects and can be rather confusing -> https://www.heatgeek.com/balancing-heating-systems-the-ultimate-guide/

Alright I see the lockshield valve on each of the rads. To confirm the job of the lockshield valve is to control how much hot water is leaving the Radiator? Does the hot water leave the rad when air temp matches TRV setting? If I tighten the lockshield to the max then no hot water can leave the Rad meaning the Rad will retain the hot water for longer no need for boiler to use more fresh gas to supply the rad with new hot water however if I loosen the lockshield valve to the max then hot water can leave the rad more easily meaning the rad will get metal cold quicker after the TRV air temp is met?

I see no indications or settings numbers on the lockshield valve so how do you know what lockshield tight/loose setting position your at to do the balancing?

The lockshield valve is simply a tap that doesn't have a handle on it.  Set it fully open and lots of water can flow through.  Turn it almost off and only a trickle can flow.  It has no idea what the TRV is doing.

If the radiator is full of water (and if it isn't, it needs bleeding), then the flow of water going in must equal the flow of water going out again.    So both the TRV and the lockshield valve can control how much water gets through.  In practice, the TRV turns the radiator on or off, and the lockshield valve sets how fast the water flows.

Balancing is done to ensure that all the radiators heat up evenly with each other.  A very quick and rough check is to wait for the heating to come on, give it just a few minutes, then go around the house grabbing hold of each radiator.  If one is still cold while another is really hot, then it's not balanced.

In particular, if you set the lockshield valve fully open on the radiator nearest the boiler, it will steal all the hot water flow, and the other radiators will take ages to warm up.  As I found with my kitchen radiator.

So I turned the lockshield valve on the kitchen radiator until it was fully off, then turned it on again a little.  Over the next few days, it did the grabbing the radiators trick, adjusting the lockshield valve on the kitchen radiator until it seemed about right, compared with the others.

To confirm the lockshield valve controls how much hot water is leaving the rad meaning closing the lockshield valve will stop the hot water leaving the rad and opening the lockshield valve does the opposite?

To confirm the TRV controls how much hot water goes in the rad?

So you saying the 2 valves needs to balance & synch with each other and match in air temp when you say must equal? If that is the case then what you adjust lockshield valve to, fully open, half open, quarter open or nearly closed & how you know which one to select?

Okay when you say close to boiler do you mean the radiators closest to boiler in distance or the radiators with the shortest copper pipes closest to the boiler because you could have a radiator upstairs on top of the boiler downstairs in the kitchen with the rad upstairs having the shortest copper pipes length to the boiler in compared to the rad in the kitchen for example even though the rad in the kitchen seems closer to the boiler you know what I mean.

I have a feeling millions of households in the UK are losing £££'s of gas per year each because the average energy user doesn't know how to run their gas central heating system efficiently and everything we discussed in this thread sounds complicated for the average energy usage to do and they require a expensive plumber to sort out all that balancing & stuff.

I'm on British Gas and Octopus energy sites and there is no mentioning or guides on what we discussed. Is it in their best interests in regards to profit not to educate their gas energy users in regards to the 4 topics and these topics are Flow Temperature, Thermostat Control, TRV and Lockshield Valves and the balancing between all 4 of these to run the heating as efficiently as possible? Especially with the sanctions on the UK from Russia not giving us cheap gas like they use to these 4 topics should be important for the population to keep warm at a affordable costs and yeah also to save the planet from climate change cause energy is being saved. 

Reed_Richards

bery_451 said:

I don't have the programmable smart TRV's, just the normal standard ones from screwfix.

Are the TRV's in general reliable and how long do they usually last before they need replacing? Are TRV's reliable as in the temp sensor in them doesn't malfunction over time and they give constant accurate readings? Do normal TRV's require calibration every so often to keep its temp sensor accuracy? What if you see like a dirty yellowed out TRV, can the dirt/grease/dust affect the temp sensor in them? Is it possible for normal TRV's to be installed fitted incorrectly? Finally how does a person fully test/diagnose a TRV to check its working as it should as in the corresponding numbers on the TRV senses the right air temperature?

I really would not worry so much about TRVs.  There are generally pretty reliable and in the event that one of them malfunctions it should be pretty obvious because the room will get too hot or too cold.  I think the most common fault is that the pin inside the valve gets stuck in the closed position.  But Google "TRV stuck pin" and you'll find plenty of advice on what to do.

bery_451 said:

To confirm the lockshield valve controls how much hot water is leaving the rad meaning closing the lockshield valve will stop the hot water leaving the rad and opening the lockshield valve does the opposite?

To confirm the TRV controls how much hot water goes in the rad?

Unless the same amount of water leaves the rad as goes in then you are in serious trouble.  More in than out and the rad will explode.  More out than in and the rad will implode.  But whereas that might happen with a rad made of thin rubber, it's not going to happen with any normal rad made of steel or aluminium.  Although both the lockshield valve and the TRV can throttle the flow, the flow in will always be the same as the flow out.

bery_451

Reed_Richards said:

bery_451 said:

I don't have the programmable smart TRV's, just the normal standard ones from screwfix.

Are the TRV's in general reliable and how long do they usually last before they need replacing? Are TRV's reliable as in the temp sensor in them doesn't malfunction over time and they give constant accurate readings? Do normal TRV's require calibration every so often to keep its temp sensor accuracy? What if you see like a dirty yellowed out TRV, can the dirt/grease/dust affect the temp sensor in them? Is it possible for normal TRV's to be installed fitted incorrectly? Finally how does a person fully test/diagnose a TRV to check its working as it should as in the corresponding numbers on the TRV senses the right air temperature?

I really would not worry so much about TRVs.  There are generally pretty reliable and in the event that one of them malfunctions it should be pretty obvious because the room will get too hot or too cold.  I think the most common fault is that the pin inside the valve gets stuck in the closed position.  But Google "TRV stuck pin" and you'll find plenty of advice on what to do.

bery_451 said:

To confirm the lockshield valve controls how much hot water is leaving the rad meaning closing the lockshield valve will stop the hot water leaving the rad and opening the lockshield valve does the opposite?

To confirm the TRV controls how much hot water goes in the rad?

Unless the same amount of water leaves the rad as goes in then you are in serious trouble.  More in than out and the rad will explode.  More out than in and the rad will implode.  But whereas that might happen with a rad made of thin rubber, it's not going to happen with any normal rad made of steel or aluminium.  Although both the lockshield valve and the TRV can throttle the flow, the flow in will always be the same as the flow out.

You can buy Radiators made out of thin rubber like a balloon these days ?

So regardless of what the TRV and lockshield valve is set to the flow in will always be the same as the flow out you meant?

FreeBear

bery_451 said: I have a feeling millions of households in the UK are losing £££'s of gas per year each because the average energy user doesn't know how to run their gas central heating system efficiently and everything we discussed in this thread sounds complicated for the average energy usage to do and they require a expensive plumber to sort out all that balancing & stuff.

It is indeed quite likely that many households are wasting energy because they have a poorly set up heating system. However, balancing radiators is not complicated, and only needs a couple of cheap thermometers to clip on the pipes, and time. Whilst this isn't the cheapest (shop around for a better price), it is quick & easy to use -> https://www.amazon.co.uk/Digital-Thermometer-Temperature-Channel-Thermocouple/dp/B0CBBRHK8Q/

Just make sure all the TRVs are set to max before attempting to adjust the lockshields (and turn the pump speed right down).

bery_451

FreeBear said:

bery_451 said: I have a feeling millions of households in the UK are losing £££'s of gas per year each because the average energy user doesn't know how to run their gas central heating system efficiently and everything we discussed in this thread sounds complicated for the average energy usage to do and they require a expensive plumber to sort out all that balancing & stuff.

It is indeed quite likely that many households are wasting energy because they have a poorly set up heating system. However, balancing radiators is not complicated, and only needs a couple of cheap thermometers to clip on the pipes, and time. Whilst this isn't the cheapest (shop around for a better price), it is quick & easy to use -> https://www.amazon.co.uk/Digital-Thermometer-Temperature-Channel-Thermocouple/dp/B0CBBRHK8Q/

Just make sure all the TRVs are set to max before attempting to adjust the lockshields (and turn the pump speed right down).

Turning the pump speed right down is closing the lockshield?

FreeBear

bery_451 said:

FreeBear said:

bery_451 said: I have a feeling millions of households in the UK are losing £££'s of gas per year each because the average energy user doesn't know how to run their gas central heating system efficiently and everything we discussed in this thread sounds complicated for the average energy usage to do and they require a expensive plumber to sort out all that balancing & stuff.

It is indeed quite likely that many households are wasting energy because they have a poorly set up heating system. However, balancing radiators is not complicated, and only needs a couple of cheap thermometers to clip on the pipes, and time. Whilst this isn't the cheapest (shop around for a better price), it is quick & easy to use -> https://www.amazon.co.uk/Digital-Thermometer-Temperature-Channel-Thermocouple/dp/B0CBBRHK8Q/

Just make sure all the TRVs are set to max before attempting to adjust the lockshields (and turn the pump speed right down).

Turning the pump speed right down is closing the lockshield?

No.

Turning the pump speed down allows the water more time to give up heat whilst it is in the radiator. Having water circulating at a lower speed means that the lockshield isn't so sensitive to adjustments when attempting to balance the system.

When my boiler was installed (about 18 months ago), the "engineer" left everything on default settings. When I attempted to balance the radiators, just a tiny tweak of the lockshield was the difference between no flow, or insufficient temperature drop. Only after turning the pump right down was I able to adjust the lockshields properly.

Reed_Richards

bery_451 said:

You can buy Radiators made out of thin rubber like a balloon these days ?

I rather doubt it but maybe try Etsy?  I suggest you get several because of their tendency to explode if you get the balancing wrong.

bery_451 said:

So regardless of what the TRV and lockshield valve is set to, the flow in will always be the same as the flow out you meant?

That's exactly what I meant.

Ectophile

To confirm the lockshield valve controls how much hot water is leaving the rad meaning closing the lockshield valve will stop the hot water leaving the rad and opening the lockshield valve does the opposite?

But the law of conservation of matter means that the amount of water going out must equal the amount of water going in.  So either valve can limit the amount of water that's going through the radiator.

To confirm the TRV controls how much hot water goes in the rad?

Yes.  But it bases that on the room temperature, and how you've set the knob on the valve.

So you saying the 2 valves needs to balance & synch with each other and match in air temp when you say must equal? If that is the case then what you adjust lockshield valve to, fully open, half open, quarter open or nearly closed & how you know which one to select?

The TRV and the lockshield valve have completely different purposes, and there's no real link between them.

You need to balance the lockshield valves from radiator to radiator, so that each one gets its fair share of the water from the boiler.

Okay when you say close to boiler do you mean the radiators closest to boiler in distance or the radiators with the shortest copper pipes closest to the boiler because you could have a radiator upstairs on top of the boiler downstairs in the kitchen with the rad upstairs having the shortest copper pipes length to the boiler in compared to the rad in the kitchen for example even though the rad in the kitchen seems closer to the boiler you know what I mean.

I meant the shortest pipework.

Given the choice, the water flow will be lazy.  If the lockshield valve is fully open on the radiator with the shortest pipe run, then most of the water flow will go through that radiator (until that room is so warm that the TRV turns off).  The radiator at the far end of the pipe run will get very little water flow and will take ages to warm up.

FreeBear

Ectophile said: Given the choice, the water flow will be lazy.  If the lockshield valve is fully open on the radiator with the shortest pipe run, then most of the water flow will go through that radiator (until that room is so warm that the TRV turns off).  The radiator at the far end of the pipe run will get very little water flow and will take ages to warm up.

Or you could whack up the flow temperature and set the pump to run at max speed. Eventually, all the water would get hot (as would the radiators). But your efficiency would fall through the floor and cost a fortune to run.

Heat Geek do an informative series of posts about balancing heating system and the benefits of running a modern boiler in condensing mode. Some of the writings are rather technical and veer off at a tangent in some spots. But still worth a read with an open mind.