Troubleshooting Guide

Do it yourself—save time and money

Residents of central and northern New Jersey have long trusted John Duffy Energy Services as a true authority in heating and cooling systems. We are happy to offer both commercial and residential customers with professional installation, maintenance, and repair services that just can’t be beat. We are also pleased to provide ways in which you can save time and money by taking your own measures to ensure your systems are working properly.

If you are having problems with any of your units, or simply wish to ensure you are using it effectively, consult with our heating and cooling troubleshooting guide below. With any additional questions, please contact John Duffy Energy Services at your earliest convenience!


I need help with my oil heating. *

I need help with my cooling system. *


* John Duffy Energy Services cannot be held liable for any adjustments you make to your heating or cooling systems. If you are unsure about the steps listed above, or have any other questions, please call our office.

Office Address
465 Mulberry Street, Newark, NJ 07114

Mailing Address
P.O. Box 5610, Newark, NJ 07105




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