Heil furnaces are well-known for reliability and accurate performance, and it can be overwhelming when choosing a model. Should you look for the most comfortable systems, Heil DC90 is a perfect contestant. It’s common for ultra-high efficiency furnaces to sacrifice temperature to obtain high efficiency, but it’s not the case for Heil DC90. The furnace will generate warm and comfortable air to the registers while providing the energy conservation you expect these days: 92% AFUE rated.
Page Table of Contents
Why does Heil DC stand out from other models?
Ingenious engineering was the primary reason for which Heil DC90 is one to talk about. The furnace comes with built-in fan control that isn’t just wiring; it also delays the fan operation so that the air warms up before it’s blown through the vents. It’s possible to let the fan at the factory preset delay time, or you may adjust it to your needs. You get to decide.
There aren’t many ultra-high efficiency furnaces with stainless steel primary heat exchanger, but Heil DC 90 is one. The secondary heat exchanger is also made with stainless steel, and both heat exchangers come with a lifetime limited warranty.
Furnaces are laboratory tested, and it was the same for Heil DC 90; it passed all tests successfully. For example, the ignition system has been laboratory tested for more than 500,000 heating cycles (it’s like 20 years) without failing.
As for installation, the furnace ticks the box of effortless installation. It comes with features for straightforward mounting, and you may also install it and vent it in various ways. It will also fit in tight spaces with narrow side clearances or height limitations.
Heil DC 90 is a furnace that allows closet installation, but also other unusual spaces. If you want to pair it with an air conditioner, you may easily match it with a Heil air conditioner.
Troubleshooting Heil DC90- the most common issues
Even if the Heil DC 90 comes with great features and will perform accurately for a long time, it’s still a furnace taking intense wear and tear. The risk for issues is always present, but you can follow up with the general recommendations for troubleshooting Heil DC90.
Let’s go over some examples of malfunctioning for Heil DC 90 and possible solutions. Furnaces are complicated machines with sophisticated mechanisms, so it’s recommended to call the professionals when an easy fix isn’t possible. Keep reading for some details.
The inducer fan doesn’t come on, blocking ignition.
Let’s say you have a Heil DC90, and the inducer fan doesn’t come on, so the ignition cycle doesn’t start. You should know that furnaces go through specific heating steps, so the process will be affected whenever something is wrong.
Should the circuit board have 119.6 volts, but you measure and get just 6 volts across the terminals going into the inducer fan, something is wrong. You check the thermostat to see the set temperature, but it’s all fine, so you cross it from the list of possible causes. You also trigger the pressure switch (suck on the inducer fan hose to see if the unit lights for a couple of seconds or not). Bypassing the limit switch shows you also that the blower starts running. Having said, you now wonder if there’s something wrong with the board.
What’s the answer?
A professional will tell you that the inducer relay won’t allow full power through. Replacing the board is the solution. You may still check to see if the control board is faulty; run a temp 120V to the inducer motor wires. Should it start, the board on your furnace is defective.
The blower runs, but there’s no heat.
The problem of furnaces running without generating hot air is quite common, and it’s not specific to Heil DC90. The power is on, the blowers begin to operate, but you see that there’s no ignition. It all happened suddenly, and you haven’t noticed any warning symptoms (so you say).
What’s the solution?
You may try to turn the power off to your furnace and wait for several minutes. Turn it back on and see if anything changes. Is the primary blower running? Have you checked the draft fan to see if it tried to start? How about the igniter? Is it in initializing?
Most of the time, the open limit circuit is the cause of the problem. The most straightforward solution is to reset the rollout switches. They should be placed outside the burner chamber, where the burners are also located, on the burner box’s side. Switch the power off and continue with pressing the button between the two wires. When you hear a click, you’ve just reset it, and the burners should fire up the moment you switch the power back on. When you don’t hear the clicking, you didn’t manage to trip it. It’s about time to call an HVAC technician for further investigation.