What Is Emergency Warmth and When Do You Want It?

That setting in your thermostat that claims emergency warmth… Ever questioned what it signifies? And is there a distinction between emergency warmth and auxiliary warmth?

A part of our job as an HVAC firm is to demystify terminology that all of us use the entire time. Typically we take it without any consideration that clients perceive us, and that they perceive their tools. That’s not all the time the case.

At Hearth & Ice, we discuss to hundreds of householders, and we regularly get questions on their thermostat’s features past the on and off buttons.

If you happen to’d prefer to know a bit extra in regards to the emergency operate, you’re studying the proper article. We may help you perceive the distinction between emergency and auxiliary features (there’s a key distinction)  with the hope which you can get by way of the winter heating season with peace of thoughts.

What Is Emergency Warmth? 

Emergency warmth is usually known as backup warmth. 

When it’s activated, it normally means one thing’s unsuitable along with your warmth pump. Both it’s not working in any respect, or it has generated warmth till the coil (positioned outdoors) may change into encased in frost, which may trigger harm. That triggers the warmth pump to enter a “defrost” mode. Throughout the defrost cycle, your warmth pump will change to cooling mode to heat up the coil and soften the ice. Whereas in defrost mode, no warmth can be transferred inside.

And if no warmth goes inside, your own home has no central warmth. Till…

That’s when the emergency operate kicks on. 

Warmth strips positioned within the air handler or electrical furnace activate and glow crimson sizzling. That warmth is then circulated by the blower by way of the ductwork. When one heating implement shuts down (the warmth pump), one other takes over.

The identical course of holds true if one thing catastrophic occurs to your warmth pump. If it shuts down for any purpose, you’ll be able to set your thermostat (some do it robotically) to emergency. That stops the sign going to the warmth pump calling for warmth, and activates the warmth strips. They may maintain your own home heat till you may get an HVAC contractor out to repair the issue.

How Does a Warmth Pump Work within the Winter? 

If in case you have a warmth pump mixed with both an air handler or a furnace, have you ever ever had the impulse to close down the warmth pump when the temperature drops under freezing? Maybe {that a} warmth pump’s effectiveness begins to drop because the temperatures do likewise. If you happen to personal a warmth pump, you’ll doubtless see this when the outside temperatures dive under 30 levels or so. It’s an indication that one thing in your system can’t carry out its job adequately.

The unit makes use of outside air and warms it earlier than it transfers the heat inside. If the temperature is simply too low, there may be much less heat to extract. It nonetheless runs, however that air that goes inside will get cooler and cooler.

If it’s under freezing and the warmth pump can solely get your property to 60, that’s fairly chilly for most individuals. Warmth pumps are environment friendly, however they can’t deal with freezing climate effectively. 

Since we stay in Columbus, the place winter temperatures typically dip under 30 levels F, householders want a backup plan for when their warmth pump can’t maintain properties snug.

Relying on the mannequin and options, warmth pumps will lose their heating effectiveness someplace between 35 and 0 levels.

The steadiness level is the place the warmth pump will not present sufficient heat to maintain your property snug. When the warmth pump can’t squeeze any extra heat from the skin air, you want backup. That’s when auxiliary warmth kicks in.

If there’s no backup plan in place, you’ll endure from the chilly, and also you additionally want to fret about your water pipes freezing.

Auxiliary warmth is like emergency warmth in that it’s utilizing warmth strips (also called coils, since they’re formed like a tightly-wound coil). The distinction between auxiliary is that your system is utilizing warmth strips along with your warmth pump. Emergency is utilizing solely warmth strips.

What Are Warmth Strips?

Warmth strips are wire components in your electrical furnace or air handler which can be heated by electrical energy, which in flip warmth the air that flows over them. Warmth strips are much like the internal workings of a toaster. They’re items of conducting metallic that get highly regarded. The official terminology is “electrical resistance warmth.”

They normally are available in 5 kW increments. Widespread packaged sizes are 15 and 20 kW.

Right here’s a listing of warmth strip sizes by kiloWatt and BTUs (British Thermal Models):

Warmth Strip Sizes (kW): BTUs

The strips gained’t come on ; {that electrical} draw may dim your lights. The system will convey them on separately.

Are Warmth Strips as Environment friendly as a Warmth Pump?

Electrical warmth is 100% environment friendly. You place a greenback in, you get a greenback value of warmth out. With a warmth pump, whenever you put a greenback in, you get three, perhaps three and a half {dollars} out of it. So when the warmth pump can’t create sufficient warmth anymore, it can nonetheless maintain working, even when the skin temperature will get right down to zero.

You’re nonetheless getting BTUs out of it, and it’s in all probability cheaper than the electrical resistance warmth. 

Although warmth strips are technically environment friendly, they eat numerous electrical energy. A 1500 kW electrical warmth bundle on your air handler is about the identical as 15 electrical heaters. That may be like an electrical heater in each room. The electrical energy invoice will soar.

Some installers or different HVAC contractors may inform you that when it will get chilly, it is best to flip the warmth pump off. That’s false. Actually, the supplemental warmth offered by warmth strips isn’t sized to warmth your complete residence. You continue to want the warmth pump to supply some warmth.

The good factor is that if one thing is unsuitable with the warmth pump, you’ll be able to flip it off and nonetheless get warmth. And the beauty of warmth strips is that they get crimson sizzling. When the blower is circulating that warmth, you’ll know immediately.

Fuel Furnaces as Emergency Warmth

You could be working an HVAC system that we name “twin gas.” It implies that you employ an electrical warmth pump with a fuel (or propane or oil) furnace. You’re utilizing two heating sources which have two completely different gas sources.

In a standard fuel system, you’re utilizing solely the furnace for heating, and also you’re utilizing solely the AC for cooling. Twin gas means you’re utilizing your warmth pump for warmth first, along with your fuel furnace as back-up. You’re going to let the warmth pump do its heating till it will get too chilly, then the fuel furnace will activate as a secondary warmth supply.

Whether or not it is a good thought largely comes right down to what the going price for electrical energy and pure fuel are. If fuel is reasonable, then relying in your fuel furnace will take advantage of monetary sense, even when it’s extra inefficient. (An ordinary-efficiency fuel furnace should function at 80% Annual Gasoline Utilization Effectivity or AFUE, or larger. Which means if you happen to put a greenback’s value of vitality into it, it offers you 80 cents of warmth, and the opposite 20 cents is waste.)

It additionally relies upon upon the effectivity of your fuel furnace. A unit in want of restore or that’s 20 years outdated is likely to be working at a price of 60% AFUE or decrease. It will possibly warmth your property, but it surely gained’t be environment friendly.

Alternatively, some fuel furnaces have an AFUE price of as much as 98%.

What’s an AFUE Ranking? – Shopping for a New Furnace   https://vimeo.com/467404742

How Does Your System Know When to Change to Emergency Warmth?

The 2 commonest emergency warmth makes use of are when the warmth pump has a mechanical failure or freezes up, and when the skin climate is simply too chilly for the warmth pump to adequately heat your property.

Your warmth pump will nonetheless run even when it might’t maintain your property heat. They used to have an out of doors temperature gauge, an out of doors thermostat constructed into them. After you configured that, it will decide when the auxiliary warmth supply would come on. 

One drawback that would come up in that state of affairs is that the outside sensor may very well be fooled if the solar had been on it. It could warmth up though the air temperature was low.

Now, it’s all run by the indoor thermostat. The thermostat indicators to the warmth pump and electrical furnace to modify over when it senses the home temperature has dropped to a sure diploma.

If you manually change to emergency warmth, you’ll in all probability get some form of indicator mild, which is able to keep on till you cease utilizing it. On a name for warmth, no sign can be despatched to the warmth pump.

The supplemental warmth can also be known as second-stage heating. The primary stage is the warmth pump working solo. The second stage is when the warmth strips kick on.

Totally different techniques and thermostats have alternative ways of figuring out when the second-stage warmth comes on to help the warmth pump, however it’s all the time computerized. The 2 phases will work collectively within the colder months, and it’s not needed to modify your thermostat to emergency warmth.

Clearly, if the emergency mild comes on by itself and stays on, your warmth pump has suffered a severe malfunction, and it is best to contact an HVAC skilled ASAP.

Staying Heat in Columbus, Ohio

Chilly climate is a truth of life in Columbus and Central Ohio. 

In case your HVAC system has been maintained because it ought to, you shouldn’t have any drawback with your property. (Pity your warmth pump can’t repair the snow-covered streets.)

You are able to do small issues to make sure the whole lot is working correctly, together with:

• Change your furnace filter when it’s soiled

• Examine your furnace to see if any water is leaking from it

• Schedule routine upkeep

• Name an HVAC professional if you happen to begin listening to new noises

Peace of thoughts will be discovered on our upkeep plan web page, the place we provide three ranges of service. Enter your zip code within the map under to see if you happen to’re in our service space. We look ahead to listening to from you.

Learn extra:

HVAC Purchaser’s Information

How you can Keep Heat When Your Furnace Gained’t Hold Up With Excessive Chilly

What’s the Distinction Between a Furnace and a Warmth Pump?