Rads on ground floor do not work

[Murdochcat]

call the person who fitted the new pump .............

 

[Mr Sparkle]

If TRV,s are fitted (Thermostatic rad valves) to downstairs rads ,check they are not stuck in closed position. It's unlikely with more than one radiator not working,but still worth ruling them out.
You can then drain one radiator ( if necessary remove it) and open one of its valves allowing water to flow out for ten seconds. There should be a strong flow. You will need to keep system pressure topped up whilst doing this. If you can ,mock up a hose connected to rad valve and out to a drain .
Do the same test on the other valve.
If no continual stream of water from valve ,there is a blockage.
Depending on result other rads may need to be tested too.

Many thanks Terry.

Okay, I will get family on the case today

1. Go to each valve (flow/return) on the ground floor rads.

2. Open then up with pressure topped up

3. The valve which doesn't release water /heavy stream is blocked/restricted

I have a standard hose. To connect the hose to the radiator valve, what additional items need to be bought?

If there is a blockage, how would you clear it?

 

[terryplumb]

Depends on the valves thread size as to what fitting would be suitable to connect the valve to hose pipe. Show us pics of both valves.
Severely blocked pipework would need section cut out and replaced. Sometimes a blast of compressed air from a foot pump ( as used to pump car tyre) into pipework may shift light blockage ,and that's probably best left to professional plumber, as precautions need to be taken.

 

[Mr Sparkle]

@terryplumb pics of the valves are attached

One end has standard TRV
The other end doesn't have a traditional lockshield. It like another TRV.

Family are reporting that as the pipework is coming out of the wall horizontally and there is no play/movement in the pipe, getting it off the wall is proving difficult.

The nuts are slacked and the rad has been moved a little to the side to try get the rad off but its not budging.

The last resort would be to cut into the plasterboard.

 

[terryplumb]

If you really can't remove the rad, drain system ,take TRV off pipe, remove rad ,refit TRV and refill system. Or try another approach ( not as good really).
Reconnect rad to valves and close both valves.
Using the air bleed valve at top of the rad ,open it with key and have large towel handy, water will trickle out for a bit then it will stop.
Leaving the bleed valve open ,and ready to contain water( bucket and towel ) ,open the lockshield valve only. Water should run out the bleed valve continuously for I full minute ( someone keeping pressure topped up).
Then close the lockshield ,and open the TRV, again let water flow for 1 full minute out the bleed valve.
If water ceases to flow from one valve ,that pipe is blocked.

 

[picasso]

I would check that hot water zone valve isint jammed open and if you have a automatic bypass that it isint stuck open.

 

[Mr Sparkle]

If you really can't remove the rad, drain system ,take TRV off pipe, remove rad ,refit TRV and refill system. Or try another approach ( not as good really).
Reconnect rad to valves and close both valves.
Using the air bleed valve at top of the rad ,open it with key and have large towel handy, water will trickle out for a bit then it will stop.
Leaving the bleed valve open ,and ready to contain water( bucket and towel ) ,open the lockshield valve only. Water should run out the bleed valve continuously for I full minute ( someone keeping pressure topped up).
Then close the lockshield ,and open the TRV, again let water flow for 1 full minute out the bleed valve.
If water ceases to flow from one valve ,that pipe is blocked.

One rad (ground floor) finally came off. Plasterboard was cutout (1)

The system has been drained for over 1 hour now.

1. The upper floor rads appear to be fully drained

2. Some of the ground floor rads were holding a lot of water even after 1 hour. So valve was cracked open to drain the rad direct (2).

3. After all this draining, water is still shooting out of the ground floor towel rail when bled (3). The towel rail is higher (in terms of heigh on the wall) compared to the all the other ground floor rads.

Does this infer that there is an airlock, or some other issue?

 

[Mr Sparkle]

I would check that hot water zone valve isint jammed open and if you have a automatic bypass that it isint stuck open.

Will get this checked out. Thanks.

 

[terryplumb]

Where on the system are you draining down from ? It's not unusual for some ,or all ,ground floor rads to be full of water when draining from one single point on the ground floor. All rads above the draining point would empty ,others may or may not ,depending on pipework layout.

 

[Mr Sparkle]

Where on the system are you draining down from ? It's not unusual for some ,or all ,ground floor rads to be full of water when draining from one single point on the ground floor. All rads above the draining point would empty ,others may or may not ,depending on pipework layout.

Ground floor rad in dining room was drained.

On the ground floor we have a living room, bathroom, dining room, then kitchen. One room after the other, in that order

With the living room being the front room and kitchen furthest away in a single storey extension.

Today we'll get the other ground floor rads off and see if there's a restriction.

Thank you.

 

[Mr Sparkle]

If TRV,s are fitted (Thermostatic rad valves) to downstairs rads ,check they are not stuck in closed position. It's unlikely with more than one radiator not working,but still worth ruling them out.
You can then drain one radiator ( if necessary remove it) and open one of its valves allowing water to flow out for ten seconds. There should be a strong flow. You will need to keep system pressure topped up whilst doing this. If you can ,mock up a hose connected to rad valve and out to a drain .
Do the same test on the other valve.
If no continual stream of water from valve ,there is a blockage.
Depending on result other rads may need to be tested too.

All the rads on the ground floor were removed.

As advised, the pressure was kept high and the
Flow and return from each rad were opened.

There was a continual stream of water from each end.

15mm flexi tail did not fit on towel rail valce so unable to fully test. However, I am confident that there is not blockage there.

Do you know the size flexi tail that will fit onto the towel rail valve?

There isn't a blockage coming into the ground fliir rads.

The only thing that I can think of is that two (of four) rads rads on the first floor take forever to heat up and when they do, they are Lukewarm at best and the return pipe is cool.

Do i need to take these rads off too to check foe the continual at the flow/return?

 

[terryplumb]

Contacted Vailliant:


According to Valiant, the ground floor rads not working suggests an airlock/ restriction.

What you have done proves the above isn't the case ,and you need to relay that to them. I assume these ground floor rads worked perfectly well prior to central heating being turned off for summer months ?
From what you have told us ,and done ,it sounds like an issue with the pump.

 

[Mr Sparkle]

What you have done proves the above isn't the case ,and you need to relay that to them. I assume these ground floor rads worked perfectly well prior to central heating being turned off for summer months ?
From what you have told us ,and done ,it sounds like an issue with the pump.

You're a star, thank you.

Contacted Vailliant and an engineer visit has been booked.

Yes, rads worked fine prior to summer

This experience has been great. As a family, we now feel confident/comfortable whipping rads off walls, draining the system, removing and fitting valves/TRV's.

Will update thread, hopefully with good news.

 

[terryplumb]

Good luck. You will need to add chemical inhibitor to your system ,as it will have been lost whilst draining down.

 

[Mr Sparkle]

Good luck. You will need to add chemical inhibitor to your system ,as it will have been lost whilst draining down.

Apologies for the delay in updating this thread

I am delighted to say that the pump was changed and the rads all work again.

@terryplumb i can't thank you enough. Your knowledge and patience was amazing. A true gem.