Hanging the heater is a fairly straightforward operation. The top of the heater has four threaded inserts which are used for hanging. Metal track is cut and located into the roof and usually spans two sets of purlins or steels, held in place with window brackets or similar fixings. Threaded bar can be wound into the heater inserts and then a lock nut, flat plate and channel nut can be wound onto the other. The heater is then raised into the air and the channel nuts located into the channel. When the lock nuts are fully tightened and the channel nuts installed correctly the heater is suspended. Alternatively the use of steel wire cables is becoming popular with eye bolts fitted to the heater and track with a steel cable looped between them.
The heater requires a gas connection connected to a suitable, permanently installed gas main. Final connections should be made with a 3/4" flexible gas hose. Purge points, test points and isolation valves should also be incorporated.
It is important that the gas main be able to provide sufficient gas to the heater. The length of the main should be measured and calculated to work out the minimum diameter of pipework. If the gas main is undersized or other appliances connected to it consume excess gas, the heater may not provide the required heat output and it's operation could become impaired.
The electrical supply and controls are fairly straightforward to install and wire in. The heater requires a 230v single phase electrical supply, installed in suitable cable and correctly protected by either a circuit breaker or fuse. The control unit is located at low level, usually fixed to a convenient wall and connected back to the heater with a multi core cable.
During operation as the fuel is burned, products of combustion are produced which are discharged out of a flue. One of the main advantages of the NVx is that the combustion fan can be aligned for a horizontal (through a wall) or vertical (through a roof) discharge. Powrmatic offer two types of terminal for both applications, together with all the necessary elbows and straight lengths of flue pipe that may be required. Sealing kits are available to prevent water leaks following installation.
Further the flue system can be room sealed for added levels of safety. A two pipe adapter used with a room sealed vertical terminal provides attachment for a second set of flue pipe which connects to the combustion air spigot on the heater. This is easy to accomplish as the spigots on the heater align up with those on the adapter. Fresh air is drawn from the outside and used in the combustion process instead of air from the space. This facility is useful in certain situations.
When the heater has been installed and commissioned by a qualified engineer it can be controlled manually from the control station or automatically by a time clock, thermostat or programmer.
A safety control box inside the heater first turns on the combustion fan for a period of time to purge the entire heater with fresh air to ensure that no gas exists within the system. Next an ignitor begins to spark, the gas valve is opened and the gas ignites.
The flame is pulled into matched burner tubes which wind around inside the heater to form six passes per tube, and finally all connect to the combustion fan. There are multiple tubes installed into each heater depending on the heat output.
As the tubes heat up, heat transfers through them into the cabinet where a large fan mounted at the rear of the heater forces cool air drawn from the space over the tubes. Hot air is expelled out of the front of the cabinet and down towards the workforce.
For tall high buildings, it is advisable to incorporate some destratification fans into the scheme, to force the warmest air at the top of a building back down to the ground. Eventually the heat will destratify and become equal. Destratification fans can contribute to energy savings with average reductions of fuel being around 15%.
The NVx range of gas fired warm air heater offers outstanding value for money, a high level or reliability and more importantly an efficient supply of warm air.
If you are considering replacing your existing warm air heater the NVx could just be your best option.
For more details of the Powrmatic NVx gas unit heater, installation or just to chat please see our website.
You can download a PDF Data Sheet for the NVx range from our website.