Danfoss HSA3 3-Port Valve Actuator

Product Information

Looking at the diagram, the grey doesn’t seem to go anywhere other than link to the cylinder stat off via the broken black line.

Today I finally got round to replacing the 3-way valve body and put a new (but not tested) actuator head on as the old one had visible signs of water damage. Wire (1) comes from the HW ON terminal, (goes via junction box) to cylinder stat, then across the stat, then from cylinder stat (via junction box ) to boiler/pump. Wire (2) comes from the CH ON terminal, (goes via junction box) to the input side of the room stat, From the output side of room stat (goes via junction box ) to the white wire of valve. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. Danfoss controls are central heating system time and temperature controls manufactured by well know controls company Danfoss.

Look out for features such as 24 hour or 7 day programmable models, 2 or 3 wire installation, frost protection and number of on/off periods per day. Do you supply these screws as spares or can you let me know the size and type so that I can source them please.

Note when replacing Sunvic SDM1901: This actuator is only suitable when the existing actuator is fixed to the valve by two screws. This is a rare situation, however, if this does happen our objective is to make the process as efficient and easy as possible.The power to start boiler then comes from cylinder stat if HW is involved or the valves orange wire if HW not involved.

Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Danfoss HSA3 3-Port Mid Position Valve Actuator 63 x 86 x 73mm (H x W x D) White, made from brass is designed for use with both copper and iron pipes inside any heating devices. I'm going to double check the two valve heads that I have, to make sure I haven't missed something, but I expect them to both to be faulty.

While doing this a second micro switch allows power out of the valves orange wire to re start the boiler. I was expecting the orange to become live once the valve had moved to the heating position but that’s not the case.

I'd normally expect the orange to become live and connect to the boiler switched live but the diagram suggests the orange is just HW. The products will work with the majority of heating systems and can be used on new installations or added to existing systems.For AC drives please contact your local sales office for fix and troubleshooting by certified service partners. I had a faulty actuator which I have now replaced, however I have lost the original wiring diagram that I made when removing the old unit from the junction box in the airing cupboard. By purchasing the actuator, you may just swap out the head of the device rather than having to replace the entire thing. normally this is fed from the HW off terminal in the programmer and the satisfied contact on the cylinder stat. When HW gets satisfied the cylinder stat breaks contact to boiler and switches power to the satisfied terminal of the stat.