New boiler nightmare

[Madrab]

All that is wired to do is shut down the flow to the cylinder when the cylinder stat is satisfied- if it isn't back to the wiring centre then there will be no switching to/from the boiler/programmer. So it'll just be power in to the junction box, out to the stat and then a switched live out to the 2 port to activate. No reason it can't be wired to the rest of the system

Putting in a wireless programmer won't fix any of that, it will only control the CH, the cylinder stat and 2 port need to be interconnected hence the cabling required.
It is an installation standard that an interlock is provided and that would require all that to be cabled up properly, he hasn't done that basic requirement either. Are you down south, if so then that install would also fall under the boiler plus regulations, which also covers the interlock requirement.

He really has tried to pull a fast one - Bodgeit and Dash Heating Services - by the sounds of it.

 

[fixitflav]

All that is wired to do is shut down the flow to the cylinder when the cylinder stat is satisfied

Unless I'm missing something, there is no motorised valve in the HW circuit

Edit - ignore that, just read a few more posts!

 

[Miseryguts]

Putting in a wireless programmer won't fix any of that

He has proposed putting in a wireless cylinder stat instead of running a cable to the wiring centre.

 

[Madrab]

He has proposed putting in a wireless cylinder stat instead of running a cable to the wiring centre.

Still won't correct the HW 2 port valve not being connected to the wiring centre. It should be programmer > cyl stat > 2 port switched live to the boiler when HW demand. So just as well running a cable to put it all together.

Unless I'm missing something, there is no motorised valve in the HW circuit

 

[Miseryguts]

I thought that was the whole point of the wireless thermostat kit - to enable remote switching of the 2 port DHW valve.

 

[Madrab]

enable remote switching of the 2 port DHW valve

Ah ok, yes, I stand corrected, now that I think about it, I believe the wireless cylinder stat kit also comes with a wireless switched relay and that will be what controls the 2 port.

Much easier to run a cable though I wouldn't have thought??

 

[snb]

A simple pH test will ascertain whether there's X800 in the system, it's acidic

Hasn’t been acidic in over 10 years since they changed the formula.

 

[Miseryguts]

More or less resolved at last!

We got a company in to do the powerflush and then the plumber returned and fitted a wireless system, which enable hot water and heating to be controlled independently. The Gas Safe Register inspection threw up some minor issues which the plumber also addressed and he reduced his bill by £500 as a contribution towards the cost of flushing.

So my mother finally has a safe, working system, albeit with one minor issue remaining: the F&E tank overflows each time the heating kicks in. Can I fix this simply by adjusting the ballcock to lower the water level in the tank?

 

[Madrab]

So my mother finally has a safe, working system, albeit with one minor issue remaining: the F&E tank overflows each time the heating kicks in. Can I fix this simply by adjusting the ballcock to lower the water level in the tank?

Nope, unless there's far too much water in the cistern to start with. If not then that's usually either a pump setting and it's pumping over or restricted pipework and the system's backing up into the F&E cistern. When the system isn't running where is the water level in the cistern?

TBH, he really should be sorting that out too.

 

[Miseryguts]

Yes, I did wonder about that. That was with the pump on fastest setting.......I'll check the level when I go later in the week.

 

[Miseryguts]

The resting water level in the F&E tank is about 2 or 3 inches below the overflow. I didn't adjust it, but instead turned the pump setting down to medium instead of high. Seems okay now - fingers crossed.

 

[Miseryguts]

Water is still overflowing with the pump on medium speed. I understand that the F&E tank is there to allow for expansion as the water heats up, but have no idea how much expansion is expected in a 150 litre system. I expect there is also an element of restricted pipework contributing to the pumping over. Should this be remedied by adjusting the ball valve to reduce the water tank level by a few inches?

 

[Mottie]

Possibly not a solution but our son had a similar problem after his boiler was serviced in a rented property. The engineer had to return several times, replacing some piping, some valves and the pump. Still didn’t solve the problem but they noticed that after the service, he had set the boiler temp to max whereas it had always been at medium. Putting it back to medium solved the problem. Was a new boiler too - probably a system problem that needs sorting but as the heating works fine and it’s not his property, he CBA moaning about it as their landlord is very good to them.

 

[fixitflav]

Water is still overflowing with the pump on medium speed. I understand that the F&E tank is there to allow for expansion as the water heats up, but have no idea how much expansion is expected in a 150 litre system. I expect there is also an element of restricted pipework contributing to the pumping over. Should this be remedied by adjusting the ball valve to reduce the water tank level by a few inches?

Overflowing and pumping over are different, I guess you mean pumping over. Could be caused by a number of things, depending on the arrangement of cold feed and open vent. Can you do a rough sketch of the layout? It would be reduced at minimum pump speed.

As you ask, expansion of water between 20 and 80°C is about 2.7%, so 4 litre for your system.

 

[Madrab]

Water is still overflowing with the pump on medium speed.

OK, time to get him back - I would be getting him to check where the cold feed and vent are located to check for restrictions/blockages - what can sometimes happen is the pump starts and as the pipework is restricted then the negative side of the system can draw water down from the Feed and Expansion (F&E) cistern, that is then made back up by the cisterns float valve, then when the pump/system shuts down the water flows back up into the cistern, causing it to overflow.

Can you check the system isn't pumping over too, there should be a vent pipe running up and over into the cistern (unless it's combined), when the boiler is running there shouldn't be any water coming out of that.