Closing Off Part of the House and HVACClosing Off Part of the House To Save Energy on HVAC – I have a Heil gas/electric package unit in my home. I, particularly, want to know, if I can close off a section to save on heating. Heating dealers have not been helpful as they hedge on whether and how this can be done with the system still running at it’s most efficient. I have closed doors to seal off area. Then closed floor registers. Should I also close air return in that area? I just read this should not be done at all as it decreases units efficiency? Will you please advise. I am thinking of closing off part of the house to save energy on HVAC. Thank you.

Closing Off Part of the House To Save Energy on HVAC

The Answer:

Hello and Thank you for emailing High Performance HVAC, Dorothy, Your registers should not be closed off as it is bad for the unit. The unit was installed based on the size of your home and the needed airflow for the house. This is designed airflow and requires all registers to be open to get the designed airflow through the unit and all the ducts. Closing off registers restricts airflow and is the same as a dirty filter which restricts airflow and causes problems with the unit.

I have seen this before and I cover this on the HVAC filter page. In a gas pack it will cause excessive heat build up inside the unit and cause the unit to trip on high limit safety if you close off too many registers as the required airflow is not moving across the heat exchange so the heat continues to build up in the heat exchanger and eventually trips this high limit safety. Leave all your registers open and make sure you have a clean filter to maximize the unit.

Closing Off Part of the House To Save Energy on HVAC - Programmable Thermostats/Insulation

The best way to get the most efficiency out of the unit is to get a programmable thermostat and run the unit only as necessary. For more information on this see the thermostat pages concerning programmable thermostats and their use. Additionally, making sure you have good windows and doors to minimize heat loss will also help. Adding insulation to your attic space and other areas will also help reduce the amount the unit runs will result in savings and additionally having a humidifier installed will also help you remain comfortable in the winter time. For more information on why a humidifier will help you remain more comfortable in the winter see the humidifiers page.

Thanks for emailing High Performance HVAC. Hope this helps you.

Closing Off Part of the House To Save Energy on HVAC

Closing Off Part of the House To Save Energy on HVACRichard Many thanks for your very prompt response! What you say ties in with what I read regarding stress on the unit. However, this Victorian “cottage” is 3,000 sq. ft. w/ 12 ft. ceilings are now too big for only my husband and I. Is there not a way we can isolate the unused space and save on heating without stressing the unit? We have done all that you suggested. Storm windows, doors, etc., except for the attic insulation.

The company that installed the unit is no longer in business and the man that I got to service it after that died. last fall. I’m in a very small town and the nearest Heil dealers seem to be 40 or more miles away. I did print a list of those I found. Haven’t called any yet as I ran across your web page. My final question is, given the size of the unit, could I convert to 2 zones somehow? And, only heat the occupied part in winter? Thanks for you patience and help.

Closing Off Part of the House To Save Energy on HVAC - Conclusion

No, unless you installed a whole new system (two new systems for zoning) or de-rating your current unit and buy another smaller unit. Also, it doesn’t have to be a Heil dealer to work on the unit. Many gas packs are very similar in design and functionality. Any qualified HVAC tech should completely understand your unit and how to repair it. Not many would know how to de-rate it though. This would likely need Heil involved to give you the engineering data for derating and exactly how to derate the equipment.

We are talking about a 2-ton system (I think) so you can’t derate too much. Generally, the tonnage is the size of the air conditioning and doesn’t refer to the heating because the system is designed for airflow for air conditioning. You don’t want to derate the air conditioning but you can derate the gas heater side of the equipment. If the unit is older than 5 years I don’t recommend this. Richard

High Performance HVAC

Closing Off Part of the House To Save Energy on HVAC

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