Hi
I have and old Oil fired boiler with two pumps one on the Central Heating circuit and one on the hot water. Currently I have a Honeywell 102E7 mini programmer controlling the system. With this controller you can either have HW (hot water) or HW and CH (Central Heating).
It is currently wired so the HW pump and boiler are always on during the program on time. If the CH is set on then the CH pump is also on during the program on time. If you look at the manual for the 102E7 (apparently made by Danfoss see here <http://www.plumbnation.co.uk/site/danfoss-randall-102e7-7-day-gp-mini-programmer-087n653400/102E7%20Guide.pdf>) this is the first diagram with a few tweaks i.e no room stat and the HW pump is also wired to output 1 (HW on).
Ok - so adding the room stat is just as in this diagram - no problem.
However, cannot seem to find anything that describes how to add a Cylinder stat to control both the HW pump and the boiler.
I think what I need to do is wire the cylinder stat to control the HW pump (insert the cylinder stat between output 1 and the HW pump) and then take the outputs from both stats to a relay of some sort with two inputs to control the boiler.
Is this correct or is there a better (cheaper) way of doing this?
If this is correct what sort of "relay" do I need?
Would it be safe to wire the boiler always on from output 1, even with the HW pump switched by the cylinder stat? Not sure that this would be of any benefit.
The boiler is an Oil fired Camray 5 (basic controls), and does not seem to require any pump overrun - at least as far as I can tell it has not had any for the past 15 or so years.
Thanks in advance
I have and old Oil fired boiler with two pumps one on the Central Heating circuit and one on the hot water. Currently I have a Honeywell 102E7 mini programmer controlling the system. With this controller you can either have HW (hot water) or HW and CH (Central Heating).
It is currently wired so the HW pump and boiler are always on during the program on time. If the CH is set on then the CH pump is also on during the program on time. If you look at the manual for the 102E7 (apparently made by Danfoss see here <http://www.plumbnation.co.uk/site/danfoss-randall-102e7-7-day-gp-mini-programmer-087n653400/102E7%20Guide.pdf>) this is the first diagram with a few tweaks i.e no room stat and the HW pump is also wired to output 1 (HW on).
Ok - so adding the room stat is just as in this diagram - no problem.
However, cannot seem to find anything that describes how to add a Cylinder stat to control both the HW pump and the boiler.
I think what I need to do is wire the cylinder stat to control the HW pump (insert the cylinder stat between output 1 and the HW pump) and then take the outputs from both stats to a relay of some sort with two inputs to control the boiler.
Is this correct or is there a better (cheaper) way of doing this?
If this is correct what sort of "relay" do I need?
Would it be safe to wire the boiler always on from output 1, even with the HW pump switched by the cylinder stat? Not sure that this would be of any benefit.
The boiler is an Oil fired Camray 5 (basic controls), and does not seem to require any pump overrun - at least as far as I can tell it has not had any for the past 15 or so years.
Thanks in advance