Lochinvar Boiler Troubleshooting

Late nights in a cold country can be amazing and full of comfort given that you have a continuous supply of hot water and radiant heat.

But what really happens when your boiler starts to malfunction? Those few frigid days will make you want to shift to a tropical country; sunbathe all day and never return back home!

However, let’s not get too carried away. Given that you own a Lochinvar boiler and have been facing issues lately, you can easily troubleshoot them at home.

If things don’t work out as you planned, there’s always a professional waiting only a call away! So, let’s hop on and start off our DIY solutions, shall we?

Lochinvar Boiler Troubleshooting

Lochinvar Boiler Troubleshooting
Photo Credit: HeatingHelp

Blank- No display shows up

Blank- No display shows up
Photo Credit: HeatingHelp

If and when there is no display on the screen, there could be a few possible underlying reasons-

  • 120 VAC is not supplied to the unit: So what next? Simply check the external line switch, fuse, or breaker to find whether that’s the problem. Remember to check the 120 VAC as well as the wiring harness ribbon cable connection attached. In case you’re unable to detect the cable, it remains in between the display board and the main control board. Once you have figured that out, just connect the harness at both points and you’re good to go!
  • The issue with the display board: Sadly, there’s only one solution to this. Get the display board replaced.
  • The Control board is acting up: Similar to the display board, the only solution is to get it changed with a brand-new control board.
  • The fuse is blown up: To troubleshoot this, simply replace the F3 fuse with a newer one. For additional help, try taking a look at the Lochinvar boiler manual provided with your boiler.

Problems with burner operation?

Problems with burner operation?
Photo Credit: YouTube [The HVAC Hacker]

Often, the burner operation might malfunction or the Lochinvar boiler ignition failure could also take place. Why does this happen and what should be done? Here’s your answer-

  • Main control board temperature: For this, simply check the temperature setting and set it accordingly.
  • Remote thermostat: When facing issues with the burner operation, make sure to review the remote thermostat setting as well. This might seem too silly, but more often than ever this is just the thing to look at!
  • Unit is locked out on fault: In case this happens, go ahead and check the fault descriptions with your owner’s manual and take the right steps.
  • Shutdown mode is on: Just take the unit out of shutdown mode and you’ll be done in a jiffy!
  • Outside air temperature above WWSD: When this is the scenario, check the location of the “outside air sensor” as well as the resistance of the outdoor air sensor. After that, simply compare them with the table provided in the Lochinvar manual and follow accordingly.

Unit modulates under 50%

Unit modulates under 50%
Photo Credit: Pinterest

Sometimes users tend to face that the unit fails to modulate over 50%. Then what steps should be taken to overcome the problem? Follow the solutions below and you’ll be done in no time-

  • Ramp delay is active: When this setting is on, the unit might start to act up. For a quick solution, check the ramp delay parameters and switch off the ramp delay features. Just in case you’re stuck on how to get it done, check the Lochinvar user’s manual that came with your boiler.
  • The boiler is being controlled by BMS: Easy way out? Just go check the BMS parameter settings and change them as required.
  • No flue temperature change: Well, this might need a little bit of work. Firstly, be certain that the flue sensor is correctly placed in the flue outlet. Next off, inspect whether the wiring at the flue sensor is damaged or loose. Once this has been examined, go ahead and check the resistance of the flue sensor. After knowing the resistance, simply compare it with the owner’s manual provided (on page 35).

Noise while operating

Noise while operating
Photo Credit: YouTube [Patrick Dickson]

This is something you might have to face as a customer when using Lochinvar boilers for years at a stretch. However, don’t panic just yet. Just like any other troubleshooting, this one has solutions too!

  • Issues with the supply of gas: When it comes to gas supply, it’s best to call a professional technician to get it checked. Nonetheless, try looking into Section 7 of the user’s manual and you might figure something out yourself.
  • Problem with the gas/air mixture: Make sure that the vent/air intake lengths do not surpass that of the maximum as instructed in the manual. For this, just go to page 46 of the owner’s manual and you’ll find your answer under the “Gas Valve Adjustment Procedure” section.
  • The burner is damaged or needs cleaning: Carefully take off the burner and inspect it. If it shows any signs of damage, replace it right away with the help of a technician. In case it’s just some dirt and debris, clean it and put it back on.
  • Low water flows: Often, the heat exchanger has little to no water flow through it. For this, go through the minimum flow rates. Once this is over, make sure that the boiler is piped properly and that both the boiler and system pumps are running smoothly. If not, better call Saul!
  • Piping system has air in it: In case this is the issue with your Lochinvar boiler, carefully vacuum out all the air from the piping system and start your boiler again.
  • Low water pressure: The system requires a minimum of 12 psi to run smoothly. If you notice a low water pressure, check the system pressure and set it to 12 psi or more and you’re done!

The pump isn’t working

Pump isn’t working
Photo Credit: HeatingForce

Occasionally, customers have had issues with the pump not being functional. The primary causes and quick fixes have been narrowed down below-

  • Fuse is blown out: The only way out of this problem is to replace the F1 fuse. However, remember to not exceed 1.8 amps when setting the pump amperage.
  • Defective pump: Similar to the previous issue, get it replaced.
  • Faulty control board: In this specific case, replacing the pump won’t be of much help. You need to get the control board replaced. So, go ahead and call the Lochinvar boiler tech support!

The relief valve stays open

Relief valve stays open
Photo Credit: Reddit

The only possible cause behind this issue is the system pressure exceeding that of the relief valve settings. Solutions? First off, merely just lower the system pressure below 30 psi from that of the supplied relief valve. The second and best way is to replace the relief valve with a higher rate one to sit back and enjoy. However, there’s one thing you might want to consider when doing this. Make sure that the higher-rated relief valve does not exceed the maximum pressure of your Lochinvar boiler.

The blower isn’t functional

Blower isn’t functional
Photo Credit: HeatingHelp

Given that the trouble you’re facing is a dead blower, make sure to follow these-

  • Faulty blower: The only solution is to replace it with a new blower.
  • Control board malfunctioning: If there are any internal issues with the control board, the blower might start to malfunction or not run at all. Sadly enough, the sole remedy is to get a new control board installed with the help of a pro technician.

With this, we have reached the end of troubleshooting Lochinvar boilers. Whatever the problem may be, be sure to reach out to the instruction manual. If giving a glimpse at it doesn’t help much, don’t waste a moment and call customer support for professional help right away. Hope you have warm and cozy days ahead!

Abdulla Zatar
About Abdulla Zatar

Hi, I’m Abdulla! Your go-to tech troubleshooter! Sharing my knowledge so that you can fix your tech issues with ease. Let’s make fixing things easy and fun!

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