TRV Default Position

[FullHouse]

Yes, it is a bungalow.
The boiler pipework goes straight into the loft, so I havent worked out the position (yet - I'll complete the diagram as soon as I can get into the loft)
The top line is not supposed to represent a pipe - sorry. I havent managed to get into the loft yet, so I dont know the pipework up there.
The IN and OUT I decided by the side the TRV was on on the rad. I noticed Bed 2 and bed 3 were the opposite way round (as I said in the final paragraph of my last post)

 

[FullHouse]

I've got into the loft and updated my diagram.



To be honest, access in the loft is difficult, so I'm not certain which pipe connects to which for each of the loops. I am confident in the diagrams for downstairs. I have also colour coded the pipes - red for those which are hot, blue for those which are cold.

The questions I have:
1) Is there an issue with the two loops with 2 radiators with TRV's being on the wrong side? If the second radiator in the loop is switched off, then the first radiator would remain cold?
2) Are the cold areas likely to be blockages, and is flushing the system the likely solution?
3) The TRVs that have seized open - is my only real option to replace them?

Thanks for your help

 

[FullHouse]

Oops - I missed the Hallway Radiator loop off of the new diagram. That's between Living Room Radiator 2 and the Bedroom 1 Loop. That seems to be functioning fine.

 

[D_Hailsham]

I've got into the loft and updated my diagram.

The diagram is much too large to view easily and there are too many superfluous links all around it and pop-ups, which I have turned off. Could you reduce the image to no more than 800x600 and post it direct using the "images" facility on this site.

Is there an issue with the two loops with 2 radiators with TRV's being on the wrong side?

TRVs can go on either side of the radiator. There will be an arrow on the metal body. If it is a single arrow it must point in the direction of flow - towards rad on the flow (hot) side, away from rad on the return (cold) side. This means that if you have an angled valve the head will be vertical on one side and horizontal the other. If there are two arrows in an L shape, the TRV can be fitted either side and the head can be horizontal or vertical as you require.

If the second radiator in the loop is switched off, then the first radiator would remain cold?

This does not happen; the radiators are independent of each other. The water does not flow through one rad and then on to the next. If you removed the second rad and all the pipe work joining the first and second rads, there would still be a path from boiler through the first rad and back to the boiler.

Are the cold areas likely to be blockages, and is flushing the system the likely solution?

If the cold area is at the bottom of the rad, it will be sludge. If the top of the rad is cold, it's air and the rad needs bleeding.

The TRVs that have seized open - is my only real option to replace them?

Have you removed the valve head and tried exerting some pressure on the pin sticking out of the body? A small amount of WD40 may free the pin. The pin should go down and then spring up when pressure is released.

 

[FullHouse]

Thank you very much for your time and your response

A resized image should be below.

This does not happen; the radiators are independent of each other. The water does not flow through one rad and then on to the next. If you removed the second rad and all the pipe work joining the first and second rads, there would still be a path from boiler through the first rad and back to the boiler

I confess that I'm a little confused by this - The conservatory and bedroom 2 radiators are served by two pipes - one goes in one end of the radiator, and the other comes out the other end of the radiator. The pipes are not directly connected with one another. Assuming the flow of hot water is like a circuit and only flows around the circuit one way, I'm unsure how hot water could flow to bith TRVs within the circuit if the radiators were off (the first radiator has the pipework pass it uninterupted, and is fed by spur pipework - so I can see how that works, but the second radiator is connected differently - it is fed directly and not by spurs). Might be best if I take a photo of the conservatory radiator (and pipework) and upload that.

TRVs can go on either side of the radiator. There will be an arrow on the metal body. If it is a single arrow it must point in the direction of flow - towards rad on the flow (hot) side, away from rad on the return (cold) side. This means that if you have an angled valve the head will be vertical on one side and horizontal the other. If there are two arrows in an L shape, the TRV can be fitted either side and the head can be horizontal or vertical as you require.

I have two arrows.

If the cold area is at the bottom of the rad, it will be sludge. If the top of the rad is cold, it's air and the rad needs bleeding.

The hot water doesn't seem to reach the radiator. By feeling the pipes, I can feel that they are warm, then a little further along they are cold. THe problem seems to be in the pipes rather than the radiator.

Have you removed the valve head and tried exerting some pressure on the pin sticking out of the body? A small amount of WD40 may free the pin. The pin should go down and then spring up when pressure is released.

Yes I have tried the same advice given for where the valve sticks closed. The valves do not seem to want to budge at all though. I have also tried WD40, but that didnt help.

 

[aptsys]

Do they all definitely have TRV's? You should have one in the same room as the thermostat with just lockshields.

 

[FullHouse]

All the radiators have TRVs.

The thermostat is in the hallway, but doesnt appear to do anything (following the wiring, it is connected)

 

[D_Hailsham]

I confess that I'm a little confused by this - The conservatory and bedroom 2 radiators are served by two pipes - one goes in one end of the radiator, and the other comes out the other end of the radiator. The pipes are not directly connected with one another. Assuming the flow of hot water is like a circuit and only flows around the circuit one way, I'm unsure how hot water could flow to bith TRVs within the circuit if the radiators were off (the first radiator has the pipework pass it uninterupted, and is fed by spur pipework - so I can see how that works, but the second radiator is connected differently - it is fed directly and not by spurs).

I have edited your pic to show how the water flows through the system. When it comes to a T junction, e.g. bedroom 2 rad, some of the water gets diverted through the rad. The rest travels on to bedroom 3 radiator. passes though the rad and jins up with the water which went through bedroom 2 rad. How much water flows through each rad is determined by the size of the radiator and the balancing of the system.
Click the pic to enlarge

Untitled

• D_Hailsham
• 20 Oct 2009
• 1

The hot water doesn't seem to reach the radiator. By feeling the pipes, I can feel that they are warm, then a little further along they are cold. The problem seems to be in the pipes rather than the radiator.

It could be that the earlier rads, living room 1 and 2, are taking more than their fair share of the flow. That means the system needs balancing - see How to Balance a heating system

Yes I have tried the same advice given for where the valve sticks closed. The valves do not seem to want to budge at all though. I have also tried WD40, but that didnt help.

If you have tried everything and failed to open/shut the valve, then it looks as if a new valve is required. Get decent ones, not £5 rubbish. Drayton or Honeywell are very good. You can frequently get brand new Drayton TRV4 on Ebay for about £10 each. They come in trade packs (small boxes) not the blister pack you see on B&Q shelves.

 

[FullHouse]

Wow Mr Hailsham - that's an awesome response - ty.

Great to see the flows on my diagram - to be honest though, it appears as I expected and (in my mind at least) - there still seems to be a problem. If we take the Beroom 2 Rad - the inflow moves into the radiator unhindered, and doesn't pass a TRV. It then passes the TRV on its exit. That cant be right can it? (or does stopping the exit of the water stop the flow and stop hot water getting into the rad? Still seems strange to me to have the TRV on the exit?)

It could be that the earlier rads, living room 1 and 2, are taking more than their fair share of the flow. That means the system needs balancing - see How to Balance a heating system

I'll give that a go - however rad 2 shuts down when it gets warm enough, so that's not overutilising I would assume. I have put the TRVs onto minimum for all the rads that were working, but the flow still didnt make it to the two rads in the final loop.

If you have tried everything and failed to open/shut the valve, then it looks as if a new valve is required. Get decent ones, not £5 rubbish. Drayton or Honeywell are very good. You can frequently get brand new Drayton TRV4 on Ebay for about £10 each. They come in trade packs (small boxes) not the blister pack you see on B&Q shelves.

Unfortunately, it looks like that's where I'm at. I dread the thought of installing them! Brilliant sounding advice too on where I should purchase them

Ty again for your time

 

[D_Hailsham]

If we take the Bedroom 2 Rad - the inflow moves into the radiator unhindered, and doesn't pass a TRV. It then passes the TRV on its exit. That cant be right can it? (or does stopping the exit of the water stop the flow and stop hot water getting into the rad? Still seems strange to me to have the TRV on the exit?)

It does not matter where you stop the flow. Don't forget that all the pipes and rads are completely full of water all the time. All you are doing is stopping the flow of water through the radiator - in one side and out of the other.

It could be that the earlier rads, living room 1 and 2, are taking more than their fair share of the flow. That means the system needs balancing - see How to Balance a heating system

I'll give that a go - however rad 2 shuts down when it gets warm enough, so that's not over utilising I would assume.

It could still be taking away some of the flow from rad 3. The flow of water through a rad is very low compared to the flow though the pipes. That why you have to balance them in order, starting at the rads nearest the boiler. In your case Living Room 1, Living Room2, Hallway, Bedroom 1, Conservatory, Bedroom2 and bedroom 3.

I have put the TRVs onto minimum for all the rads that were working, but the flow still didnt make it to the two rads in the final loop.

Turning the TRVs down won't have any real effect. Turn all the lockshield valves (opposite end to TRV) off on the "good" rads and check if the "bad" ones heat up. If they do the balance is wrong. When you shut the LS valves, make a note of how many turns are needed to shut the valve. If they are all the same, the system has not been balanced. When finished, open up the original number of turns.

Unfortunately, it looks like that's where I'm at. I dread the thought of installing them! Brilliant sounding advice too on where I should purchase them

It's not a difficult job. I helped my son to change his valves from wheel type to TRVs on seven rads and it took a morning.