Chillaire Limited recently carried out a gas fired heating installation project at Proserve in Kenilworth, who specialise in Marine Construction Systems. Chillaire replaced 2 x existing Powrmatic PGUH330 old model type gas fired warm air heaters with 2 x new modern Powrmatic NVX90F warm air heaters.

The existing Powrmatic model PGUH330 warm air heaters were each providing 96 kW of heating.

Chillaire Limited heating design engineers carried out a heat loss assessment and re-assessed the requirement, they were assisted by Martin Arden, a heating systems sales and design engineer with Powrmatic Limited

Chillaire installed 2 x new Powrmatic NVX90F replacement heaters, each providing 90 kW of heating, a combined heating output of 270 kW per hour. There is an option to have a third one added later or have de-stratification fans installed instead.

The work was carried out by Chillaire over 3 days using scissor lifts and a mechanical lift to bring down the existing 500 kg Powrmatic PGUH330 heaters suspended from the main roof of the Proserve warehouse. The 2 x new Powrmatic NVX90F heaters, weighing around 300 kg were then lifted up using the same mechanical lift and secured into place off the warehouse roof in place of the old removed Powrmatic PGUH heaters.

The existing gas mains pipe was modified to suit each new heater gas connection. We also installed a new control panel with new Powrmatic controllers and modified the existing electric wiring to suit the new controls.

Importance of De-stratification Fans

In large high roof type buildings de-stratification fans are essential and very energy efficient, heat will always rise and tend to stay up at high level unless there is a means of bringing it to low level and maintaining it at floor level on a constant basis.

We have proven on many occasions for clients who have heating problems in their large warehouse buildings, where no de-stratification fans have been fitted and we have measured and proven temperature differences between 5°C to 8°C from floor level to roof level. The higher the roof level, the higher the temperature difference from floor level to roof level.

Another way to maintain good even temperature through a building is to have a large air handling unit with a powerful fan with a supply duct installation with nozzles to direct the hot air to low level with low level return air, this method creates and maintains a constant air flow circulation from high level to low level. The large air handlings unit can have gas fired burner units or LPHW coils linked to a standalone boilers.

The 2 x new Powrmatic NVX90F warm air heaters installed at Proserve had specially ordered 45 degree angled deflector hoods fitted to each heater to which ensure that the warm supply air is thrown downward, towards the floor where it provides the heating effect, before it starts to rise to the roof level.

Usually with low roof levels, over time the heat difference throughout the day does eventually even out and you get a more constant temperature reading across the whole space in an open warehouse.

Air Conditioning - Heating - Ventilation