Powermax 155x by-pass timer

[elcharlie]

My built in programmer/timer stop working. Boiler only works when switch kept to continuous hot water but this option did not provide me with heating. Looking at the wiring diagram I found a solution to by-pass the programmer/timer. I would like your views on this. My solution is on the wiring board connect port 24 (power from always hot water on switch) with port 18 (power to the thermostat). It is my understanding that this will get heating always on but always controlled by my thermostat as long as the switch is kept to hot water continuously. Your views on this would be much appreciated. I got it working and I have not found any issues yet. Note: I have safely disconnected the original wire to the port 18 from the programmer just in case.

 

[ericmark]

I will guess a micro switch has failed in your motorised valve, or what ever the boiler uses to ensure it does not run if the valves or pump is not open or running. And personally I would want to correct the real fault.

I found an instruction set which shows the timer connects terminal 27 to terminal 28 for the central heating to work, however I will guess it will not work as I will guess some thing else is wrong, as in the main timers are quite robust and although the clock may fail manually turning it on normally works.

Personally I would find true cause of failure, as bridging random terminals you may well also be bridging safety devices.

 

[elcharlie]

I checked everything. All valves etc working. The only issue was that power was not coming to terminal 28 from the programmer. The only thing I did was to send power to the thermostat continuously from the always hot water on switch. Looking at the wiring diagram I do not see why would I affect any safety device. I am just powering the pump if the thermostat ask for heat and the water is not too cold inside the boiler (cold -start). All the safety devices are part of the ignition sequence and I will never touch that. The boiler works and stop firing when hot and I get hot water and heating fine. But please welcome more views. I might miss something

 

[ianmcd]

what you have done is fine, but as you already know you will have to leave the hw switched on,The in built programmers on these are stupidly expensive an fail constantly, if you want a permanent fix fit an external 2 channel programmer

 

[andytw]

Your programmer is repairable. See advert on eBay. https://www.ebay.co.uk/itm/223443450487

 

[paulwinter4]

Sorry to jump in on this thread but Can anyone give me detailed instructions on how to install a hive 2 channel programmer to a powermax 155x and how to disconnect integral timer panel if necessary. A detailed wiring diagram would also be appreciated. Thankyou

Read more: https://www.diynot.com/diy/threads/hive-and-powermax155x.522723/#ixzz5nQ0VJdsR

 

[andytw]

Discussed here if it helps...

https://www.diynot.com/diy/threads/powermax-155x-hive.515937/#post-4291713