• 100% Satisfaction Guarantee
Comfort Specialist, HVAC Technician
Category: HVAC
Satisfied Customers: 1368
Experience:  Master Lic. holder for HVAC & Gas, Contractor, Estimator, Designer, Air Balance Certified, LG Master Commissioner, UNC Cert. holder for Industrial Ventilation
66600370
Comfort Specialist is online now

# After coating a large commercial roof and ducts with a heat

### Resolved Question:

After coating a large commercial roof and ducts with a heat reflective coating the return air temp is now 3 degree C cooler on average (23 degree C day)
Comments from Air Conditioner service provider.
They noticed a marked difference in running time of the main shopping centre unit.
Their comments were that the Air Conditioner units would always be running whenever the ambient temperature was above 21C.
Now it gets up to around 28C before they kick in.
How do I calculate the energy saving
Submitted: 4 years ago.
Category: HVAC
Expert:  Comfort Specialist replied 4 years ago.

Wvfan79 :

Hello there! I'm Norman but you can call me Norm. Let's see what I can do to get you some answers today. I'm ready to get started whenever you are.

Wvfan79 :

A general rule of thumb is that energy savings can be 2% to 4% for every 1 degree difference in thermostat set-point; either raising the cooling setpoint or lowering the heating set-point. That would be for a 24 hour period.

Wvfan79 :

To estimate the savings from set-points during unoccupied periods; prorate the percentage based on the number of hours of set-back / set-up.

Wvfan79 :

Here's an example, if you are raising the cooling temp by 10 degrees for a 12 -hour period, estimated savings can be between 10% and 20%.

Wvfan79 :

That can be calculated like: 2% to 4% per degree * 10 degrees * (12 hours/24 hours) = 10% to 20% savings

Wvfan79 :

However, these estimates are just percentages of your electrical specifically used for heating and cooling. This is not a percentage of your total electric bill.

Wvfan79 :

Also, actual savings will depend on your specific climate zone. Savings as a percentage of your heating and cooling bill will be greater in mild climates than in higher/harsher climates.

Wvfan79 :

Wvfan79 :

If you have more questions and you reply to this post it may take me awhile to respond. I will try to check back once in awhile but glitches in the chat system do not allow for notifications of chat replies.

Wvfan79 :

Customer:

Hi Norm I am sorry for the no reply . the setting on my work pc did no show your data.

Comfort Specialist, HVAC Technician
Category: HVAC
Satisfied Customers: 1368
Experience: Master Lic. holder for HVAC & Gas, Contractor, Estimator, Designer, Air Balance Certified, LG Master Commissioner, UNC Cert. holder for Industrial Ventilation

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

### What Customers are Saying:

• You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
< Previous | Next >
• You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
• Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
• This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
• Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
• I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
• Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
• Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland

• ### Phil

#### Satisfied Customers:

5389
Retired HVAC/ Electrical & Boiler contractor. Industrial
< Last | Next >

### Phil

#### Satisfied Customers:

5389
Retired HVAC/ Electrical & Boiler contractor. Industrial

### gotoman for ac

#### Satisfied Customers:

4999
51 years of experience install design and repair of all makes and models of AC

### Rick Mather

#### Satisfied Customers:

3133
35 years experience, HVAC

### Matthew

#### Satisfied Customers:

2014
14 years experience in the HVAC field of service, installation, Manual J & D calculations

### Kenton Guidry

#### Satisfied Customers:

963
12 years install/service experience.

### Rick Ridley

#### Satisfied Customers:

871
Retired But have had 30 years on the tools, Ex CORGI