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Tempstar 40VA Transformer for T8MPT050B12B1 — 115V to 24V | Ships Today
Tempstar

Tempstar 40VA Transformer for T8MPT050B12B1 — 115V to 24V | Ships Today

SKU: 1172810-GEN Brand: Tempstar

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

Overview

This OEM control transformer (part number 1172810) steps line voltage down from 115V to 24V to power the low-voltage control circuit in your Tempstar T8MPT050B12B1 furnace. Rated at 40VA, it supplies the thermostat, control board, gas valve, and relays. A failed transformer is one of the most common causes of a completely dead furnace — no thermostat display, no call for heat, and no response from the control board. Replacing it restores 24V power to the entire control system.

Specifications

Spec Value
Part Number 1172810
Type Control Transformer
Brand Tempstar / ICP / Heil
Primary Voltage 115V
Secondary Voltage 24V
Rating 40 VA
Fit OEM Replacement

Compatibility

Designed for the Tempstar T8MPT050B12B1 furnace and other ICP-family equipment (Tempstar, Heil, Comfortmaker) that uses OEM transformer 1172810. Verify your primary/secondary voltage and VA rating before ordering.

Installation Guide

  1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
  2. Access — Remove the furnace control/junction panel.
  3. Document — Photograph the primary and secondary wiring before disconnecting.
  4. Remove — Unbolt the transformer from its mounting bracket and disconnect all leads.
  5. Install — Mount the new transformer and reconnect primary (line) and secondary (24V) leads per your photo.
  6. Test — Restore power and confirm 24V output and a normal heat call.

Signs You Need a Replacement

  • Blank thermostat with no low-voltage power
  • No 24V reading at the R and C terminals
  • Burnt smell or visibly scorched transformer windings
  • Repeated blown low-voltage fuse on the control board

Shipping & Returns

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

Shipping Information

  • Orders placed before 3PM CST ship same business day
  • Standard delivery: 2-5 business days
  • Express shipping available at checkout
  • Free shipping on orders over $75
  • Tracking number emailed upon shipment

Return Policy

  • 30-day returns on unused parts in original packaging
  • Electrical parts (capacitors, contactors, control boards) are final sale once installed
  • Email info@nationalhvacparts.com to initiate a return
  • Refunds processed within 5-7 business days

Frequently Asked Questions

Does this Transformer fit my Tempstar T8MPT050B12B1 — 115V to 24V | Ships Today?
Yes. This is the factory-specified OEM transformer for the Tempstar T8MPT050B12B1 — 115V to 24V | Ships Today. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.
How do I replace the transformer on my Tempstar T8MPT050B12B1 — 115V to 24V | Ships Today?
Difficulty: Medium (30–45 min)
Step 1: Turn off breaker. Step 2: Photo wiring connections. Step 3: Disconnect wires from old transformer. Step 4: Remove mounting hardware. Step 5: Install new transformer, reconnect wires matching voltage ratings. Step 6: Verify 24V output with multimeter.
My thermostat has no power. What failed?
Thermostat with no display = failed 24V transformer (or blown control board fuse). Check the 3A/5A fuse on the control board first ($1–$5 fix). If fuse is good but no 24V output from transformer, replace transformer.
Is this transformer compatible with Bryant or Payne too?
Many Tempstar parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.
Should I use OEM or aftermarket for my Tempstar transformer?
OEM recommended for reliability and warranty compatibility. OEM parts match exact factory specifications for proper fit, performance, and safety. While aftermarket alternatives cost less upfront, the risk of improper fit and reduced lifespan usually makes OEM the better value long-term.
How fast does National HVAC Parts ship?
Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.
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Mike Rivera
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