Caleffi 551003A Air SeparatorThe Discal Air Separator delivers dependable air elimination for hydronic systems, minimizing noise and performance losses. The Caleffi 551003A model features a 3 4" NPT female connection for straightforward in line installation and reliable performance. Designed to optimize hydronic systems by separating and venting air, this unit helps maintain flow, efficiency, and heat transfer. The 551003A uses a removable cap for easy service and quick access to

pilot duty 120–600 VAC

engineered for safe startup and reliable operation

normally closed (N

3/4" threaded connections

Caleffi 521619A thermostatic and pressure balanced mixing valve delivers precise temperature control for domestic hot water

Choose ASCO 8221G009 for dependable control in pumps

Watts 374A-3/4 Boiler Pressure Relief Valve is a trusted safety device for hot water space heating boilers

This electrode (ignitor) replacement ensures quick startups

5' sample hose

reducing energy waste and minimizing downtime in your AO Smith equipment

Engineered to meet OEM specifications for reliable service

and electrical noise in busy furnace rooms