Allparts Equipment & Accessories 60105 Ignition Control Board - OEM Automatic Ignition System fits Enerco MHU and HSU Series Overhead Compact Garage and Workshop Natural Gas and Propane Fired Forced Air Furnaces up to 125,000 BTU's

Why I picked up the 60105 control board

My garage unit heater started doing the classic intermittent-ignition dance: inducer would spin up, I’d hear the igniter click, a small flame would catch, then everything would shut down and retry. After a few lockouts, I’d be stuck resetting power to coax one more cycle out of it. Cleaning the flame sensor and verifying the pressure switch helped for a bit, but the symptoms pointed at the ignition control. For Enerco’s Mr. Heater/Heatstar overhead units (MHU/HSU series), the 60105 control board is the OEM brain that runs ignition, blower timing, and safety interlocks. I swapped it in to see if it would restore the heater to steady, predictable operation.

A note on the unit: mine is a compact 75,000 BTU natural gas model. The 60105 is specified for MHU/HSU series up to 125,000 BTU and handles both natural gas and propane configurations (gas type is determined by your appliance’s components and orifices, not the board itself).

Build and fit

Physically, the board is compact and tidy: about 4.5" x 5.7" x 1.5". Connector labeling is clear, and the terminal layout closely matches the factory board it replaces. The LED status indicator is well-positioned for line-of-sight with the burner door open, which makes diagnostics easier. Solder joints looked clean, the board felt sturdy, and the standoffs on my heater aligned without any drilling or slotting. This is an OEM-style piece, so tolerances and footprint felt familiar—nothing “universal” or cobbled together.

The board’s job is straightforward: coordinate inducer pre-purge, manage the igniter and gas valve during the trial for ignition, confirm flame via flame rectification, run the blower on a timed profile, and monitor the limits and pressure switch. It also provides fault-code flashes from the onboard LED, which are invaluable when you’re trying to decide whether you have a board problem or a sensor/switch issue upstream.

Installation: straightforward with a few precautions

If you’ve replaced a furnace control board before, this is a clean swap. Start with power off and gas off. I snapped photos of the wiring harnesses and low-voltage terminals before disconnecting anything, and I recommend labeling spade connectors with masking tape if your harness isn’t keyed. The board sits on four posts in my unit; it popped off and the new one pressed on with a snug fit.

A few tips from the install:

• Take ESD precautions. Handle the board by the edges and avoid touching components.
• Verify your model and series. This board is targeted at MHU/HSU compact overhead heaters up to 125,000 BTU.
• Inspect the pressure switch tubing and condensate path (if applicable). A split hose or blockage can mimic board issues.
• Clean or replace the flame sensor. Even with a new board, a dirty sensor will cause nuisance flame dropouts.
• Check your ground. Flame sensing relies on a good equipment ground; corroded lugs cause headaches.

Total time was under 30 minutes including photos, wire transfer, and a quick vacuum of the burner compartment.

First ignition and ongoing performance

The first start-up sequence was textbook. Inducer on, brief purge, igniter energized, gas valve opened, flame established and sensed, then the blower kicked on after a short delay. More importantly, it repeated that consistently. Over the past several weeks of cold-morning use, the heater has behaved predictably with no random lockouts. The ignition timing felt a hair more decisive than with the tired original board—no extended clicking or drawn-out retries.

The blower off-delay also seemed properly calibrated, clearing residual heat without overrunning long after the flame is out. I didn’t detect any odd cycling of the inducer or spurious short-cycling that sometimes crops up when a failing board misreads a switch input.

Diagnostics and fault codes

One of the most useful aspects of this board is the simple LED diagnostic. Before replacing the board, I had a recurring flame-sense code during retries; afterward, a steady “all-clear” idle flash with no faults. I intentionally pulled the pressure switch tube once to test its sensitivity, and the board immediately flagged the error. That kind of clean, readable feedback reduces guesswork and helps separate real component failures from wiring or airflow problems.

If you’re troubleshooting, the LED codes combined with a multimeter across the pressure switch and limit string will get you most of the way to root cause. The board makes it obvious whether it’s waiting on a safety input or failing to see flame, which is the diagnostic clarity you want in a cold shop at 6 a.m.

Reliability and safety

Functionally, this is the control center for the heater’s safety chain. It won’t fix poor venting, a clogged heat exchanger, or a bad limit switch—but it will honor those safeties without drama. After the swap, high-limit and rollout tests tripped and reset as expected. The board’s lockout behavior is conservative and predictable: it retries within the normal limit, then shuts down cleanly if conditions aren’t right. That gave me confidence to let the heater run unattended while I worked in another part of the building.

As with any control board, longevity is the question you only answer with time. The build quality inspires confidence, and being an OEM-style replacement tends to help with thermal and electrical compatibility. I’ll update my notes if anything changes long-term, but so far, so good.

What could be better

• Documentation. The quick-start sheet explains connections and LED codes, but a wiring diagram and a timing chart would make field troubleshooting even faster for less-experienced techs.
• Compatibility clarity. It’s designed for specific MHU/HSU models. If you’re outside that family, this isn’t a universal board. That’s fine—just make sure buyers see a clear model list before they order.
• Price versus aftermarket. You can find cheaper universal boards, but you’ll trade integration and sometimes safety logic. In my case, the clean drop-in fit justified going OEM.

Tips for a successful swap

• Verify thermostat and 24V transformer output. Low secondary voltage will mask as ignition problems.
• Confirm gas type setup. The board doesn’t change natural gas vs. propane; your unit must be properly configured for the fuel in use.
• Replace brittle spade connectors. Loose connections at the gas valve or limit string cause intermittent faults that look like board failures.
• Give the flame sensor a fresh surface with a Scotch-Brite pad and wipe it clean. Don’t sand aggressively.

Who this board is for

• Owners of Mr. Heater/Heatstar overhead units in the MHU/HSU series who are seeing intermittent ignition, nuisance lockouts, or erratic blower timing.
• Technicians who value a plug-and-play OEM solution with correct mounting, connectors, and safety logic.
• Garages and workshops where downtime matters, and a fast, correct fix beats adapting a universal board.

If you’re dealing with a furnace that’s not in this series, or you like customizing timings and fan profiles, this isn’t your board. Look toward a universal with the right spec—but be prepared for a more involved install and a higher chance of misconfiguration.

The bottom line

The 60105 control board did exactly what I wanted an OEM replacement to do: install cleanly, align with existing wiring and mounting, and bring the heater back to consistent, safe operation. The ignition sequence is reliable, the blower control feels right, and the LED diagnostics simplify both initial troubleshooting and any future service. It won’t cure problems caused by poor maintenance or airflow, but it provides a solid, predictable platform for a heater that’s otherwise in good shape.

Recommendation: I recommend the 60105 control board for anyone with a compatible Mr. Heater/Heatstar MHU or HSU unit up to 125,000 BTU who needs to replace a failing control. The OEM fit, straightforward installation, and dependable ignition behavior justify the choice, especially in a workshop or garage where uptime and safety matter. If your heater falls outside the supported models, skip it and choose a board designed for your system—but for its intended use, this one hits the mark.