Output from the normal cylinder thermostat is. Obviously people should refer to the exact wiring diagram for the unvented hot water cylinder that they are wiring and not take it for granted that this would be correct for all.

Nl 7021 Cylinder Stat Wiring Download Diagram
Unvented cylinder wiring diagram. Looking for a basic understanding and help with terminals. The combination of pressurisation and hot water could lead to. After reading countless discussion threads on various forums i hadnt been able to work out whether the zone valve was only intended to be an emergency shut off or whether it should also shut off whenever the control. All products are insulated. All electrical wiring must be carried out by a qualifi ed electrician and be installed in accordance with current iee wiring regulations. I basically have the cylinder 2 port valve and pump.
The cylinder is a purpose designed unvented water heater. Terminal 14 common went to c on the hts3 thermostat. I have attached a diagram of an example of the wiring for a heatrae sadia megaflow unvented indirect hot water cylinder in case anyone else is interested in this. What youve said is consistent with a couple of wiring diagrams i found online for other manufacturers of unvented cylinders. Do not switch on if there is a possibility that the water in the cylinder is frozen. The original system is a drayton bi flo control packs.
28 2 port mechanical diagram 29 2 port electrical diagram 30 3 port mechanical diagram. The cyclone air unvented range of cylinders are manufactured with quality and precision to the fore. Before any work switch off the mains supply to the appliance and the mains water supply. The outer casing is a combination of resilient thermoplastic mouldings and plastic coated corrosion proofed steel sheet. Hi hoping someone can help me out. An unvented cylinder is sealed under pressure and overheating will cause the pressure inside to rise to dangerous levels.
As part of a rewire im connecting up an unvented system and separate boiler for the heating. I have replaced an vented cylinder with and unvented cylinder and am having difficulty replacing the single cylinder thermostat wiring with a dual thermostat. Danger this cylinder is unvented and as such becomes pressurised when in operation. The cyclone air brand signifies the next generation of hot water cylinder development. Wiring is based on the standard y plan with the addition of a high limit thermostat and a 2 port motorised valve. These are shown at the bottom right of the diagram.
The unit has a stainless steel inner vessel which ensures an excellent standard of corrosion resistance. Boiler pump and stat for heating all working but i have no experience of unvented cylinders. The pre plumbed cold feed assembly ensure consistency and quality every time. The original wiring from the lwc1 wiring centre was. The internal expansion provides a neat installation. Unvented mains pressure water heaters 120 150 170 210 250 and 300 litre capacity indirect models installation and servicing instructions pack contents the centerstore unvented cylinder water heater incorporating immersion heaters and thermal controls l factory fi tted temperaturepressure relief valve l cold water combination valve assembly.