Heating Control Problems?????

[chrish_1977]

Evening Guys!

Got a problem with some heating controls. The plumber has replaced boiler, controller, 3 port valve and room thermostat (all Honeywell).

Problem I've got is heating works fine, hot water works fine, but when they are both on together the cylinder thermostat shuts off and shuts off both heating and hot water. I have double and triple checked the wiring and is all wired as per Honeywell Y plan wiring diagram from Honeywell. The only thing that is not Honeywell is the cylinder thermostat I think this may be the culprit but don't want to start replacing stuff just for the sake of it.

Anyone come across this problem before?? I would be really grateful for any help!!

Thanks

Chris

 

[Lighthouse Phil]

When the stat reaches temp, does the boiler go off too...if not, where is the valve diverting the hot water too if the pump is still running.
is it possible the room stat and cylinder stat are crossed over in the wiring loom?..room stat at temp so cuts off the boiler / cylinder stat is bypassed by room stat??

 

[chrish_1977]

Hi Phil, everything shuts off, pump, valve the lot. have tried swapping the stat wires over etc. all the wiring is within 2 foot of everything else bar the boiler and room thermostat and they are dedicated cables. Its starting to get on my nerves now as all the wiring is correct as per the diagram, the only iffy thing i have is the tank stat, and i am looking at getting a honeywell one too so that everything is the same and eliminates third party wiring etc. But I think my plumber has cocked up somewhere and doesnt want to admit it.

 

[Lighthouse Phil]

Plumbers....When i was at college they were called "the lesser trades" lol
Good luck with the stat anyway..hopfully the honeywell one will sort it out for you

 

[Guest111]

It has to be a connection problem,cylinder stats only have 2 wiring options known as BOR(NORMALLY CLOSED) AND MOR(NORMALLY OPEN) Break On Rise opens the circuit at the required temperature and Make On Rise closes the circuit at required temperature,I,ve worked on quite a few in the past and in the situation you describe its a wiring fault in 99% of all cases.

 

[chrish_1977]

I'm sure your right phil d, it's just the more I look at it the less I'm finding what the fault is, but I'm pretty sure the tank stat isn't doing what it's supposed to do, when I checked across the terminals I had 230 when the stat was set to call for hear and 63 volts on the third terminal. Getting annoyed with it now ha ha

 

[HandySparks]

Get yourself a large piece of paper and draw it out. Supply in at the top, programmer below, followed by room stat and cylinder stat, zone valves, boiler and pump at the bottom. Put the core colours against each end of the wire and label all the terminals.

When you've got enough info to draw the whole control circuit as installed, you'll probably find that the answer's in front of you.

 

[chrish_1977]

I have the Honeywell app for my phone so all the wiring diagrams etc for all the different types and have checked that several times (I guess that could be wrong) I have even checked against another wiring diagram I have and it's all correct (as much as I can see of course) so the only difference is the tank stat, but I will give your way a try handysparks and go from there, will post back with an answer ( cause I know you all at the edge of your seats with this one ha ha ha)

Thanks guys

 

[BillyTheSparks]

Any luck with this one then OP?

 

[chrish_1977]

Sorry guys. Was letting it go for a couple of weeks to see what's happening, wired it as per Honeywell wiring diagram. And educated the owner that if they wanted more hot water not to raise the tank stat but press the hit water button on the wiring controls, so far everything doing as it should, but I think that the 3port valve may have been the culprit.