• Replaces Honeywell V4073A: Direct replacement powerhead for a V4073A or V4073A1039 mid position valve, and for a TSA3 actuator head
• No draining needed: The head fixes to the valve body with two screws, so a failed head is a same day fix rather than a full system drain down
• Head only, valve not included: Supplied with two fixing screws, for when the motor or switch has failed but the valve body is still sound
• Mid position action: Drives the diverter movement that lets a Y Plan system feed the radiators and the hot water cylinder at the same time
• Standard wiring: Runs from a 230 V AC supply and wires terminal for terminal into the existing wiring centre, with the auxiliary switch that fires the boiler and pump
• Manual lever: Holds the valve open by hand for filling, venting or commissioning, then releases back to automatic operation

The LavaTherm 3 Port Motorised Valve Actuator Head is the electrical half of a mid position valve, supplied on its own as a replacement part. Mid position heads work harder than two port heads because they hold an intermediate position rather than simply driving open and closed, so the motor or the auxiliary switch is usually what fails first while the brass valve body stays serviceable. Replacing the head alone avoids draining the system.

Please note: this listing is for the actuator head only. The valve body is not included.

The head is secured to the valve body by two screws, and a pair of fixing screws is supplied in the box. With the electrical supply isolated, unscrew the old head and lift it away, seat the new head on the same spindle, screw it down and transfer the wiring across terminal for terminal. No water is lost and no joints are disturbed.

In service the head gives a Y Plan system its three working states: resting on the cylinder port for hot water only, driven fully across for heating only, and held in mid position to serve both circuits at once. An auxiliary switch makes once the valve has moved to the calling port, passing a switched live on to fire the boiler and run the pump. A manual lever holds the valve open for filling, venting or commissioning.

This head is the direct replacement for the actuator on a Honeywell V4073A or V4073A1039 mid position valve, for a TSA3 three port actuator head, and for the LavaTherm 3 port valve. It fits both 22 mm and 28 mm valve bodies, with the same spindle and screw fixing pattern as the original.

A failed actuator head is one of the most common causes of a heating or hot water outage. Because this powerhead swaps over without draining the system and wires terminal for terminal into the existing wiring centre, it is the kind of repair that gets the heating back the same day the part arrives and can save an engineer call out.

Installation must comply with current wiring regulations.