Worcester Bosch 18/25 Wiring Problem

[headlesschicken]

Hi, I have had a New Worcester Bosch Heatslave 18/25 combi boiler fitted and the plumber has used a Twin Channel Digital plug in programmer and a Honeywell CM927 Wireless Programmable Room Thermostat. The problem I have is the two seem to be conflicting against each other, the only way to make boiler work is to put Hot water to ON on plug in programmer then Match the timed settings on the plug in programmer on the boiler with the wireless programmer roomstat. With this setup I cannot turn the heating on outside the times i have programmed into both programmers. I am wanting to know 1. Can I remove the plug in programmer? 2. How to wire the wireless programmer so it controls the Central Heating i.e. where do the A- B terminals go on the boiler? 3. Will my DHW still work with the plug in programmer removed or will i need to alter wiring on boiler?

Your help will be very much appreciated as i am getting no where with the plumber that fitted the boiler he says thats how it should work but I want to be able to have heating on outside programed times if i'm home early for example. Regards Martin

 

[picasso]

looks like your plumber has cocked it up, if the wiring was correct you would have to put the plug in programmer ch on constant and let the wireless programmer/stat control the ch, the hot water setting should not have any effect on the ch, the wireless stat should have live and neutral supply from the boiler and then A connected to LS and B connected to LR, you might need another "plumber" to have it sorted.

 

[dcawkwell]

If you are are anywhere near Doncaster I can sort you out.
Just had to fix another oil boiler that a plumber has put in who didn't
know what he was doing with an oil boiler.

Send me a personal message.

 

[D_Hailsham]

Why did he install a two channel programmer when you have a combi boiler?

Using the Select buttons, set both CH and HW to ON. HW will then be heated whenever you turn on the tap and CH will be controlled (times and temperatures) by the CM927.

 

[picasso]

Why did he install a two channel programmer when you have a combi boiler?

Using the Select buttons, set both CH and HW to ON. HW will then be heated whenever you turn on the tap and CH will be controlled (times and temperatures) by the CM927.

This combi has a heat store which the programmer controls.

 

[D_Hailsham]

This combi has a heat store which the programmer controls.

I wasn't aware of that - thanks for the information.

In that case, just set the CH to ON using the Select button and control the HW by the built-in timer.

 

[Boilerman2]

Surely the answer to this is Simple!!

set the hotwater times on the on-board programmer but set the C.H. to CONTINUOUS - then set the CM Controller to switch the heating as required it really must be that SIMPLES???

 

[headlesschicken]

Surely the answer to this is Simple!!

set the hotwater times on the on-board programmer but set the C.H. to CONTINUOUS - then set the CM Controller to switch the heating as required it really must be that SIMPLES???

The Hot water has to be on "ON" to work and if i set the CH on continuos then the heating is on 24hrs a day the wireless programmer wont turn the heating/boiler off at all. the wireless programmer doesnt seem to control the boiler, it only seems to turn boiler on and off when it reaches desired temperature during the hours set into the boiler programmer. It seems like its only using the roomstat part and the built in controls and programmer dont seem to be able to overide the plug in programmer. Its driving me mad at the moment definately NOT SIMPLES!

 

[headlesschicken]

If you are are anywhere near Doncaster I can sort you out.
Just had to fix another oil boiler that a plumber has put in who didn't
know what he was doing with an oil boiler.

Send me a personal message.

Hi Thank you for your response Sorry I dont know how to send a personal message, Im near York unfortunately.

 

[D_Hailsham]

The Hot water has to be on "ON" to work and if i set the CH on continuos then the heating is on 24hrs a day the wireless programmer wont turn the heating/boiler off at all. the wireless programmer doesnt seem to control the boiler, it only seems to turn boiler on and off when it reaches desired temperature during the hours set into the boiler programmer.

Definitely a wiring problem.

It appears that the installer has not removed the link within the clock - this is necessary for fully pumped systems and explains why HW has to be on for anything to work.

Do you have the instructions for the plug-in programmer?

If not, they are here.

See page 4 (Fitting the Programmer) for info about removing the link.

It might also be a good idea to check that the 4-way link is in place.