Baxi solo 24 he problem

[MZR]

hi all

fitted a baxi solo yesterday with a new room stat everything was working fine before i went as i had to commission the new boiler ! customer set the programmer after i left then a few hours later the boiler has no power ? i have checked the programmer which switches the hot water and heating on but there's still no power to the boiler or the zone valve ?

i rang baxi who advise to hardwire the boiler and pump to a plug check they work ok which they did.

would it be the programmer thats not switching the power to the boiler and zone valve or would the zone valve be faulty ? everything works fine the room stat has power the cylinder stat has power the pump is wired from the p/f on the boiler terminal so if the boiler has no power nor does the pump

any advise would be good as it worked fine yesterday now i scratching my head on what the cause of no power and how it fix it ???

thank all

 

[bewsh]

When you put the programmer on, do you get voltage to the room/cylinder stat?

 

[bewsh]

If not, programmer is knackered

 

[MZR]

yes we get voltage mate

 

[Ermintrude]

3 port me stinks

 

[bewsh]

Ye, sounds like mid-pos is at fault.
Check voltages inside the mid-pos. And check resistance through synchron motor (usually about 2.5kohm)

 

[MZR]

but would that cause no power at the boiler ?

 

[Mike Jackson]

It's a matter of elimination. Work through the sequence of controls until you get to the point where you have no live feed. Sit down with a Y plan diagram and trace the route the power takes. I'd be looking at a loose or damaged wire between the JB and the boiler because the SL to the boiler comes via the cylinder stat when there's a call for hot water or heating and hot water and via the microswitch on the 3 port when there's a call for heating only.

 

[Billy Bob Bob]

you may find this useful
http://ccs.infospace.com/ClickHandl...1&mid=9&hash=26C2A26150C7589D7948E1A3B533F071

 

[MZR]

many thanks for that Gasman ive been on the wiring plans all day to try and work them out and still its confusing as there are so many ! lol

if the zone was faulty would this cause the boiler to have no power ? the boilers live is connected to the zone valve Orange which is the switch live, so if the zone valve was not switching or was faulty the zone valve would not switch power to the boiler ? (does that make sense or is it me ?)

 

[Billy Bob Bob]

many thanks for that Gasman ive been on the wiring plans all day to try and work them out and still its confusing as there are so many ! lol

if the zone was faulty would this cause the boiler to have no power ? the boilers live is connected to the zone valve Orange which is the switch live, so if the zone valve was not switching or was faulty the zone valve would not switch power to the boiler ? (does that make sense or is it me ?)

if theres power from the clock a dead mot valve would cause it ,there would be no pwer to the boiler or pump

 

[bewsh]

Is it a mid-pos or 2-port valve?
Check the orange wire from the zone valve, if there's 240vac there, then there's a connection issue somewhere, if there's not, then you need to work backwards to see where the voltage is lost.

 

[Billy Bob Bob]

however thinking on it most 3 ports fail to dhw,mike more or less summed it up

 

[MZR]

im confused now i must be the worst with electric

 

[Dotty]

Moved off open forum.

 

[arran197]

If It's an s plan, so has 2 zone valves, the orange wires will both go to the switched live for the boiler. If you've got voltage on the orange wires at the junction box and if it is wired correctly, the boiler should have a switched live going to it. The power goes clock, stat, valve, boiler/pump. On a y plan, if the clock and stat are calling, DHW will always come on.

You need to check that there's no voltage on the neutral to the boiler, if there is then the boiler won't work and there is a neutral fault. Are they having any other electrical work done?