How to size hydronic heating pipes: water flow from load and temperature difference, velocity and Pa/m criteria, Darcy–Weisbach friction, a worked 200 kW main, and the index circuit that sets the pump head.
Heating Pipe Sizing: Flow, Velocity, Pa/m and Pump Head Read More »
A practical, step-by-step EN 12831 heat loss calculation: design conditions, U-values, thermal bridges, ground and unheated spaces, ventilation, and one living room calculated in full to 904 W.
Heat Loss Calculation Step by Step: EN 12831 Worked Example Read More »
Size a fire pump to NFPA 20 in clear steps: net pressure, standard ratings, curve and pressure checks, motor power, suction rules and jockey settings, with a worked example.
Fire Pump Sizing to NFPA 20: Rated Point, Curve Checks and Jockey Read More »
A conventional panel knows the zone; an addressable panel knows the device. Here is how each system works, a simple way to choose, and the alarm sound and visual rules that apply to both.
Conventional vs Addressable Fire Alarm Systems Explained Read More »
Good loop design is mostly bookkeeping: an address budget with 20 % spare, isolators that respect the 32-detector rule, zones a fire fighter understands and cables that survive the fire. A two-loop office example shows every step.
Fire Alarm Loop Design: Addresses, Isolators, Zones and Cables Read More »
What TN-S, TN-C-S, TT and IT earthing mean for fault current and protective devices, with the same circuit worked through on TN-C-S and TT.
TN-S vs TN-C-S vs TT Earthing: Systems Explained (Plus IT) Read More »
How to size supply ducts with the equal friction method, check velocities for noise, count fitting losses and calculate the index run that selects the fan, with a fully worked office floor branch.
Duct Sizing Guide: Equal Friction, Fittings and the Index Run Read More »
The essentials of a cooling load calculation – heat gain versus cooling load, solar and shading, internal and latent loads, coil load and zone diversity – with a worked west office and a full office floor.
Cooling Load Calculation Basics: Solar, Internal and Latent Loads Read More »
How to design a clean agent system for a server room to NFPA 2001: design concentration, agent quantity, safety limits, discharge and hold time, enclosure integrity and venting.
Clean Agent System Design for Server Rooms (NFPA 2001) Read More »
How to size a cable for both current capacity and voltage drop using mV/A/m values, with typical limits and a worked sub-main plus final-circuit example.
Cable Sizing for Voltage Drop: Formula, Limits and Worked Example Read More »