Thermostats:
Q, Why do I need to provide a neutral for my thermostat to work?
A, Most bi-metal thermostats require a neutral to complete the circuit that powers an accelerator heater and possibly an indicator lamp. Bi-metal thermostats require the accelerator heater to give a small differential and give consistent switching.
Q, I have three wires but your thermostat only requires two?
A, A thermostat that only requires two wires is usually connected to switch the live conductor. Live supply would connect to the common and switched live to N/O (normally open for heating systems) or N/C (normally closed for cooling systems). The neutral can be made safe and not used.
Q, I want to add a thermostat but don’t want to install any wiring?
A, There are Radio Frequency (RF) thermostats available that can work over considerable distances and control the system without the need of wiring.
Q, The RF thermostat doesn't seem to control the heating consistently any more?
A, It is possible that the thermostat was installed with default factory preset coding. If another unit is installed nearby (also with default coding), or another appliance is operating on the same frequency, you may need to change the coding to avoid cross talk.
Q, I want to use your Towerstat RF. Can I use the existing timer to control on/off times?
A, It is possible to use your existing programmer/timer to control the on/off periods. Set your Towerstat RF to "P1" and follow the wiring instruction at the following link click here
Q, I have a programmable room thermostat and it has a mind of it’s own. It switches on when it should be off?
A, Check that the setback (economy) temperature is set low enough. Overnight the temperature drops and if the ambient room temperature drops below the setback (economy) set-point, the heating will come on.
Q, My programmable room thermostat changes program overnight?
A, You have to select which day or days you want to program. Select the day or days then enter the program number you want.
Q, I changed the batteries in My RF room thermostat and it's not working as it was?
A, After replacing the batteries it may be necessary to press the reset button and set-up your parameters once more. If too much time elapsed during battery changing it is possible that the unit reset or it's logic became corrupt. After resetting ensure that the correct program is selected for the day group required and the setback (moon) temperature is set low enough to avoid the heating switching on over night (off periods). Setting the moon to seven degrees will ensure that the heating will not come on during setback (off) periods.
Q, The LCD display on the thermostat has disappeared and doesn’t control the heating?
A, If your thermostat is battery powered check that they have sufficient charge to operate your thermostat. If your thermostat is mains powered, check that the power is still present.
Q, The RF thermostat doesn’t seem to bring the heating on?
A, For systems with an existing time control, set the heating to constant (fixed on). If there appears to be no communication between transmitter and receiver refer to the instruction on commissioning procedures.
Timers/Programmers:
Q, The boiler doesn't fire even though the timer says it should (heating or hot water)?
A, Because the timer or programmer controls the boiler through a thermostat, if the ambient room temperature (heating) or water temperature in the hot water cylinder (hot water) are higher than the set-point on the thermostats the boiler will not fire.
Q, How do I set my 24 hour analogue timer to come on between 6am and 8am?
A, You will need to set your timer to the current time by aligning the outer dial with the arrow marker on the face of the timer. You then move the tappets outward between the times you want the timer to be on. Please see the PDF for more a more detailed explanation click here
Q, The display is constantly flashing, How do I change the battery in my digital timer?
A, If your digital timer (Tactic 371+,5xx+, IHT-Digi+, SB-Digi+, Talento 3xx+,4xx+,7xx+) display is constantly flashing it is most likely the battery is drained and will need to be replaced. Please follow the step by step guide click here
Q, I can program my digital timer when running on the battery but it will not switch the output?
A, All of the digital timers that have a built in battery backup can be programmed and settings changed etc. whilst running on the battery. The full display and switching of outputs can only be achieved once the power supply has been connected.
Q, The day indication on the display keeps flashing and I can’t program or override?
A, The days need to be set for the real-time. The clock needs to know the time and day before the programmer will allow any programming to take place. Refer to the user instructions for setting the clock.
Q, The heating is on constantly and the times do not appear to control anything?
A, Check that the override has not been set to “Fixed on”.
Q, The heating won’t come on?
A, Check that the override has not been set to “Fixed off” or the thermostat set too low.
Q, I can’t get the hot water and heating to work independently?
A, Check that the programmer/timer is configured for a fully pumped system. The Towerchron QE2 and QM2 can be configured for gravity or fully pumped systems. Please refer to the installation instructions or
click here for more detail
Q, Can I use the Towerchron QE1 or QM1 on a combination boiler?
A, Yes, They have volt free outputs and are compatible with combination boilers.
Q, Why doesn't the neon indicator on my QM1 illuminate?
A, If your QM1 is switching Volt Free or a low voltage the neon will not illuminate. The neon indicator requires 230V to operate.
Q, The hot water neon indicator on my QM2 comes on when it should be off?
A, The neon indicator will illuminate if there is a back feed to the "hot water on" terminal. To overcome this you may need to add a relay. Please open example diagram click here
Q, Why does my digital programmer reset and sometimes freeze?
A, The main reason a digital programmer will appear to reset or suffer program corruption is a surge/spike in the mains supply or from the load itself. If you suffer power cuts or see your lights dim or brighten, your power supply is fluctuating. If your programmer is connected to a control circuit via a contactor or relay you could be suffering from "Back EMF". To overcome both of these situations please refer to our suggested suppression techniques 
Suppression techniques.pdf
Q, My programmer/timer is used to switch lighting. It turns the lights on but will not turn them off again.
A, When switching lights (especially any type of discharge lighting, e.g. fluorescent or 'SON' lamps) you have to take the startup/inrush current into account. This can be fifty times the normal running current or more for a number of milliseconds. The inrush overloads the output contacts which then remain stuck in the on state. When specifying a timer for lighting control you should allow for this type of inrush current value.
Q, I want to switch lighting, how can I do this if it will overload my timer/programmer?
A, Instead of switching the lights directly you should use a contactor. The timer/programmer is only used to switch the contactor and the contactor will take the high current load. When using a digital timer with a contactor you should use surge protection to avoid back EMF from the contactor's coil. Please see "suppression techniques" above.
Q, When installing a Towerchron QE1 or QE2 the LCD display will not show?
A, This can happen sometimes when the QE1 or QE2 is first energized. Press the "reset" button and the LCD display will appear.
Q, How do I mount a Towerchron QE1 or QE2?
A, The Towerchron QE1 & QE2 are mounted onto a standard backplate. This must be secured to a solid surface. Please click here for a step by step guide..
Valves:
Q, I have a Tower mid-position valve. Can I use it as a diverter valve?
A, Yes, join the white and grey wires together and supply them with 230V AC to spool the valve open. The default port that is closed is port "A". When power is supplied to white and grey the valve will motor until port "B" has closed. Remove power and the valve will return to Port "A" being closed and port "B" open.
Q, I have a six wire MV2-28C 2 port zone valve. Can I change this for a 5 wire VAL228MV?
A, Yes, you will need to add a changeover relay to make the VAL228MV work in the same way. Please download the schematic showing how to connect a relay Click_Here.
Q, I have an existing system and want to add a zone. How do I wire it?
A, Once you have added your zone valve you will need to wire it in parallel to your existing heating control valve. If you have a Y-Plan system (Mid position) click here. If you have an S-plan system (two 2 port valves) click here.
Q, I have a Tower valve. Can I change the actuator without having to remove the valve and drain down the system?
A, Yes, the "VAL322MP & VAL222MV" Tower valve actuators can be replaced independently of the valve. This is the same process for both valves. Please click here for guide
Q, Why should the actuator be positioned no more than 45 degrees from vertical?
A, This is to ensure that should a leak occur that water does not come into contact with the electrics.
Q, I have noticed that after calling for heating only, when no longer calling the valve does not return to close port “A”. The manual override leaver is loose and the motor appears to be powered. Is this a fault?
A, No, the valve will remain in that state until power is removed or hot water is called for. The synchronous motor is rated for running in a continuously stalled state and the valve is designed to operate in this way.
Q, A 2 Port valve I have fitted appears to slam shut ?
A, Check the flow direction. There is an arrow on the body of the valve to show the correct orientation.
Q, I have a Tower mid-position valve and when calling for heating only, the valve spools open but does not fire the boiler?
A, The grey wire must be connected to the cylinder satisfied and then to the programmers “hot water off” terminal. This provides 230V AC to the grey wire when the hot water is satisfied or not in demand. Without the grey wire connected in this way, when calling for heating only the valve will open until it reaches the mid position. Power on the grey will allow it to travel fully and energize the boiler and pump.
