Top Pro

$35/service call

(waived if hired)

A/C unit size

Responds in about 3 min

Introduction: I have been doing HVAC servicing for 20 years and it has become a passion for me. I know all the processes from the inside, my goal is to understand the cause of the breakdown and eliminate it using the most modern and safest methods for health. I won’t just fix a temporary breakdown, I will fix your equipment for many years of service. I have all the necessary tools, supplies expense, modern measuring equipment, my knowledge and experience. And I use all this for my happy clients. My highlight is that I love my job and do it conscientiously and efficiently.

Current Top Pro

Hired 12 times

Serves Rancho Cucamonga, CA

Background checked

3 employees

19 years in business

Payment methods

This pro accepts payments via Cash, Check, Credit card, and Zelle.

Featured Projects

19 photos


Customers rated this pro highly for work quality, professionalism, and value.

Very good 4.6

9 reviews


Read reviews that mention:

pro avatar
Ivy K.
Feb 11, 2024

Hired on Thumbtack

Hired on Thumbtack

A vent was leaking in the house i was using a soup pot to collect the water. I am extremely happy with the service received from DZO. He was on time and extremely respectful to my home custom The repair was completed efficiently and quickly and it’s guaranteed I will definitely call again

Details: Repair • Outside • Roof • House

Central Air Conditioning Repair or Maintenance
pro avatar
Robert B.
2 days ago
Dennis quickly and accurately diagnosed the issue, efficiently completed the repair, and provided valuable maintenance tips. The service was prompt, professional, and reasonably priced. Now our AC is running perfectly again! I highly recommend DZO HVAC and Dennis to anyone in need of reliable and skilled AC repair services.
pro avatar
Nicholas B.
3 days ago

Hired on Thumbtack

Hired on Thumbtack

I am happy with the quality of Dennis's work ethic. He arrived on time, with a smile presenting his eagerness to meet me, listen, and diagnose my heating & air conditioning system needs. He kept me abreast with fixing the problems. I will use DZO HVAC Group INC services again and ask for Dennis. I offer a five-star assessment of the work performed. Thank you, Nicholas

Details: 3 or more • Need professional to recommend size • Home

Window, Wall, or Portable AC Repair or Maintenance
pro avatar
Dominic W.
4 days ago
I highly recommend Denis for anyone in need of HVAC services. His professionalism, skill, and customer service are top-notch. Thank you, DZO HVAC, for a job well done!
pro avatar
Asher H.
6 days ago

Hired on Thumbtack

Hired on Thumbtack

Denis was very dedicated to get the job done. Perfect fix

Details: Repair • Unit won't turn on or off • Attic • Ground floor • Commercial

Central Air Conditioning Repair or Maintenance
Background Check

Denis Zemliakov

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