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Tempstar 40VA Transformer for T8DNL100F14B2 — 115V to 24V | Ships Today
Tempstar

Tempstar 40VA Transformer for T8DNL100F14B2 — 115V to 24V | Ships Today

SKU: 1172810-GEN Brand: Tempstar

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Texas CMBL #19328542014
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Overview

This OEM control transformer (part number 1172810, TRANS 115>24 40VA) steps 115V line voltage down to the 24V control voltage that powers the thermostat, gas valve, igniter circuit, and control board on the Tempstar T8DNL100F14B2 furnace. Rated at 40VA, it supplies stable low-voltage power to the entire control system. A failed transformer leaves the furnace completely unresponsive — no thermostat, no ignition, no blower.

Specifications

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

Compatibility

Direct-fit replacement for the Tempstar T8DNL100F14B2 furnace and other ICP/Heil/Comfortmaker models using the 1172810 40VA 115-to-24V control transformer. Confirm the VA rating and voltage match your original before installing.

Installation Guide

  1. Safety First — Disconnect power at the furnace switch and breaker, and verify zero voltage with a multimeter at the transformer leads.
  2. Access — Remove the control-compartment service panel.
  3. Document — Photograph the primary (line) and secondary (24V) wire connections before disconnecting.
  4. Remove — Disconnect the leads, remove the mounting screws, and lift out the old transformer.
  5. Install — Mount the new transformer, then reconnect primary and secondary leads exactly per your photo.
  6. Test — Restore power and confirm 24V across the secondary and normal furnace operation.

Signs You Need a Replacement

  • Furnace is completely dead — no response from the thermostat.
  • No 24V measured on the secondary terminals with line power present.
  • Transformer is hot, discolored, or has a burnt smell.
  • Repeated blown low-voltage fuses 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 T8DNL100F14B2 — 115V to 24V | Ships Today?
Yes. This is the factory-specified OEM transformer for the Tempstar T8DNL100F14B2 — 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 T8DNL100F14B2 — 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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