Heat Recovery
Overview
Selection Chart
Selection Example 1 – Equal Supply and Extract,
No Ancillaries
Selection Example 2 – Uneven Supply and Extract, Ancillaries
Site Engineering Services
Literature
O & M
Overview
- • 10 standard sizes
- • airflow up to 4.3 m3/sec
- • double skinned construction
- • side access as standard; bottom access, stacked arrangement and external options possible
- • high density infill for low breakout levels
- • 20mm Mez frames to all spigots
- • fitted hangers for drop-rod installation (channel base on models 650, 800, 950 & 1100)
- • filter access panels fitted with quick release fasteners
- • backward curved impellor direct driven by low energy EC motor
- • fan blades statically and dynamically balanced in accordance with ISO 1940/1 and balancing quality G6.3
- • single phase 230V fan motors are pre-wired to speed controllers and isolator
- • high efficiency counter-flow heat exchanger typically >80%
- • face and by-pass damper with fitted open/close motor
- • electric heater battery or LPHW heating coil
- • selection of fitted controls available
- • panel filters to G4 grade, mounted in slide-in channels
- • supply panel filters to F7 grade
- • extract panel filters to M5 grade
- • maximum air temperature 40ºC
- • manufactured in UK to ISO 9001
- energy efficient, environmentally friendly, economical
EC motors

Selection Example 1 – Equal Supply and Extract,
No Ancillaries
- Consider the example;
- • Supply and extract air volume 0.1m3/s @ 125Pa
- • SFP<1.4W/l/s
- Would result in;
- • HRPSL310EC
- • SFP < 1.2W/l/s (remember, the graphs show per fan, so double any resultant)
- • PHXE efficiency 85%
- • Fan speed < 7V ~ 70%
Selection Example 2 – Uneven Supply and Extract, Ancillaries
- Consider the example;
- • Supply air volume 0.1m3/s @ 125Pa
- • Supply air volume 0.1m3/s @ 125Pa
- • SFP<1.4W/l/s
- • LPHW heating coil
- • 50mm airway supply attenuator
- Would result in;
- • Additional 17Pa supply pressure for LPHW coil
- • Additional 11Pa supply pressure for attenuator
• Additional 11Pa supply pressure for attenuator
• Additional 11Pa supply pressure for attenuator
- • Exact heat exchanger efficiencies will have to be checked with the Sales Office
- • Supply side
- o 153Pa pressure
- o SFP < 0.7W/l/s
- o Fan speed < 8V ~ 80%
- • Extract side
- o SFP < 0.7W/l/s
- o Fan speed < 8V ~ 80%
- For the uneven fan duty points the SFP for the unit has to be recalculated;
- • Calculate the motor absorbed power for supply and extract fans
- o SFP * Airflow = Absorbed Power
- o Supply = 0.7 * 0.1 = 0.07kW
- o Extract = 0.7 * 0.12 = 0.084kW
- • Combine the motor absorbed powers to give total unit absorbed power
- o 0.07kW + 0.084kW = 0.154kW
- • Divide by the supply or extract airflow whichever is greater to give unit SFP
- o 0.154kW / 0.12m3/s = 1.28W/l/s
o 0.154kW / 0.12m3/s = 1.28W/l/s
Site Engineering Services
- AVT (SES) offers a full refurbishment, maintenance, repair and installation service. PHONE or EMAIL TO SEE WHAT WE CAN DO FOR YOU! Tel: 01264 356415: Email: ses@airventtechnology.co.uk.