No Power To Thermostat: A Simple Repair Guide

Your house is getting very cold today. You walk over to your wall to turn the heat up. The small plastic box has a completely black screen. You have absolutely no power to thermostat wires right now. This blank screen means your entire heating system is totally dead. We will show you exactly how to fix this annoying problem today.

Checking The Simple Things

Testing New Batteries

Many wall boxes use regular small batteries to run the digital screen. You should pull the plastic face off the wall gently. Look at the back of the plastic screen for small battery slots. You must put fresh new batteries inside the plastic slots. Put the screen back on the wall and see if it lights up. This simple trick fixes a blank screen most of the time.

The Main Breaker Box

Your wall box gets its main power from your big metal breaker box. You need to walk down to your basement and open the grey metal door. Look for a heavy black switch that is flipped the wrong way. You must push the black switch all the way off and then push it hard to the on side. This resets the electrical power flowing to your indoor heating machine. Read the Energy.gov Heating Systems guide to learn how your system uses electricity safely.

Need Emergency Electrical Help?

Is your house freezing cold right now? Did new batteries fail to turn your blank screen back on? Our expert team can find the hidden electrical problem fast today. We carry all the best tools in our work trucks.

Expanded Repair Costs Table

System Component	Main Purpose	Expected Lifespan	Estimated Part Cost	Estimated Labor Cost
Thermostat Batteries	Powers the digital screen	One single year	$5 to $10	Free to do yourself
Low Voltage Wire	Carries power through walls	Fifteen to twenty years	$20 to $50	$100 to $200
Electrical Transformer	Changes the power level	Ten to fifteen years	$40 to $80	$150 to $250
Indoor Control Board	Acts as the main brain	Ten to fifteen years	$200 to $400	$300 to $500
Brand New Thermostat	Replaces a broken wall box	Five to ten years	$100 to $250	$100 to $200

Finding Hidden Problems

The Indoor Safety Switch

Your indoor furnace has a secret switch inside the metal door. The machine turns off completely if this metal door is slightly open. You must go check the heavy metal panels on your indoor machine. Push the metal doors very hard to make sure they are closed tight. The machine will send power back to your wall box when the door is safe.

A Broken Safety Fuse

Your indoor machine has a tiny plastic fuse hiding on the main computer board. This tiny plastic piece breaks on purpose to stop electrical fires. A broken fuse cuts all the power going to your wall box immediately. You must hire a trained worker to open the machine and replace this tiny piece. Check HomeAdvisor Electrical Costs to see local rates for safe wiring repairs.

Dealing With Bad Wires

Broken Wall Wires

Mice and bugs love to live inside your dark house walls. These pests often chew right through the thin wires connecting your wall box. Chewed wires stop the electrical signals from reaching your indoor machine. A worker must run a brand new wire from your basement up to your living room. Read our Thermostat Clicks But No Heat guide to learn about broken control signals.

A Burnt Transformer

Your house sends massive electrical power to the indoor heating machine. A small metal box called a transformer lowers this massive power for your wall screen. A burnt metal transformer will leave you with no power to hvac systems at all. You will smell burnt plastic if this metal box gets too hot and melts. You must never touch these dangerous metal parts with your bare hands.

Need Help Paying For Repairs?

A burnt computer board costs a lot of unexpected money to replace. We offer easy online loans to help you pay for these safe electrical repairs today. You can pick a very small monthly payment that fits your family budget.

FAQ

Why is there absolutely no power to thermostat in my living room today?

Your digital wall screen is likely completely blank because the internal batteries are totally dead or a safety fuse blew inside your main heating machine.

How do I fix a blank screen when my thermostat has no power at all?

You should first try pulling the plastic face off the wall and installing brand new batteries to see if the digital screen lights back up immediately.

What causes a sudden loss of power to my entire indoor heating system?

A tripped electrical breaker in your basement or a loose metal safety door on your furnace cabinet will instantly cut all power to your heating equipment.

Can I safely replace the tiny plastic fuse inside my indoor furnace by myself?

You absolutely must never touch the internal computer board by yourself because the machine holds deadly high voltage electricity that can cause a fatal shock.

How much money does a professional technician charge to fix bad thermostat wires?

A licensed professional will typically charge you between one hundred and two hundred dollars to safely test the bad wires and install a brand new digital wall unit.

Conclusion

A blank screen on your wall is a very frustrating problem during a cold day. You should always check the batteries and the basement breaker box first. You must call a professional worker if the problem lives inside the heavy metal heating machine. Expect to pay about one hundred and fifty dollars for a safe electrical repair today. Call our expert team to test your dangerous wires safely. Use our HVAC Services page to schedule a fast repair visit right now.