ICP 40VA Transformer for SH10016B — 120V to 24V Class 2 | Ships Today

Overview

This OEM 40VA control transformer (part number 1540352) converts incoming 120-volt line power to the 24-volt Class 2 control voltage used by your ICP SH10016B furnace's thermostat, gas valve, and control board. The entire low-voltage control circuit runs on this transformer, so when it fails the system cannot respond to a call for heat. The 40VA rating supplies plenty of capacity for typical residential control loads. Typical failure symptoms include a dead thermostat, a furnace that will not fire, a repeatedly blown low-voltage fuse, an acrid burning odor, or a transformer that buzzes and overheats.

Specifications

Compatibility

Direct OEM replacement for the ICP / Tempstar / Heil SH10016B and other ICP-family units that use the 1540352 transformer. Verify your existing unit is a 120V-to-24V 40VA transformer before ordering.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, then confirm zero voltage at the transformer terminals with a multimeter.
2. Access — Remove the furnace service panel to reach the control compartment.
3. Document — Photograph every primary and secondary wire before disconnecting anything.
4. Remove — Label and disconnect the 120V primary and 24V secondary leads, then unbolt the failed transformer.
5. Install — Mount the replacement, reconnect primary to line voltage and secondary to the 24V circuit per your photo.
6. Test — Restore power, verify 24V across the secondary, and confirm the control circuit energizes on a heat call.

Signs You Need a Replacement

• Thermostat and controls completely dead with line power present
• Low-voltage control fuse blows immediately on power-up
• No measurable 24V at the secondary terminals
• Humming, excessive heat, or a burnt smell at the transformer

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.