PCB Design Review Request: High voltage AC-DC converter

[santinilor]

Hi,
I've just finished routing a two-layer PCB and need some feedback, especially on the safety side, since it deals with 220V AC mains.

The board's purpose is simple:

• Take 220V AC in (J1) and output regulated 5V DC (max 8A) via an IRM-45-5 module.
• Switch a 220V AC heating element on and off (output at J2) using two AQH3213 solid-state relays (U1, U2).

My biggest worry is the 220V AC section. I need to ensure this is safe and properly isolated.

(Layout images show Top Layer = Red traces, Bottom Layer = Blue traces.)

• HV Clearance: I used 1.6 mm minimum clearance between 220V AC traces (top/bottom layers) based on the KiCad calculator. Does this look adequate/safe around all HV components (fuses, terminals, SSRs, varistor)?
• HV Trace Routing: Any issues with the routing of the AC power and switched heater lines (J1, J2) that could be problematic?
• Isolation and Ground Plane: The 5V DC ground plane is on the bottom layer (blue fill). Is there any spot where this DC ground plane compromises the required isolation/creepage distance from the 220V AC components or traces?

Component Overview:

• Board Type: 2-layer PCB.
• AC I/O: J1 (220V AC Input) and J2 (Switched 220V AC Heater Output).
• DC Supply: IRM-45-5 module providing 5V DC (max 8A).
• Switching: 2x AQH3213 Solid-State Relays (U1, U2) controlled by MOSFET Q1.
• Protection/Filtering: Varistor, Fuses (F1-F3), and filtering chokes (L1, L2).

Any feedbakck is appreciated

Thanks for the help!