# Do CO2 (R-744) HPWHs pencil out in very cold garages versus indoor installations?

**URL:** <https://home.renovation.reviews/t/do-co2-r-744-hpwhs-pencil-out-in-very-cold-garages-versus-indoor-installations/19965>\
**Category:** Trade Talk\
**Tags:** garage\
**Created:** [August 4, 2025, 3:17pm UTC](https://home.renovation.reviews/t/do-co2-r-744-hpwhs-pencil-out-in-very-cold-garages-versus-indoor-installations/19965 "2025-08-04T15:17:05Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![reno\_questions](https://home.renovation.reviews/user_avatar/home.renovation.reviews/reno_questions/32/2758_2.png) [@reno\_questions](https://home.renovation.reviews/u/reno_questions)\
**Post date:** [August 4, 2025, 3:17pm UTC](https://home.renovation.reviews/t/do-co2-r-744-hpwhs-pencil-out-in-very-cold-garages-versus-indoor-installations/19965/1 "2025-08-04T15:17:05Z")

</div>

Do CO2 (R-744) HPWHs pencil out in very cold garages versus indoor installations?

---

<div class="post-metadata">

**Author:** ![Tim\_Michael1](https://home.renovation.reviews/user_avatar/home.renovation.reviews/tim_michael1/32/6294_2.png) [@Tim\_Michael1](https://home.renovation.reviews/u/Tim_Michael1)\
**Post date:** [August 5, 2025, 10:07am UTC](https://home.renovation.reviews/t/do-co2-r-744-hpwhs-pencil-out-in-very-cold-garages-versus-indoor-installations/19965/2 "2025-08-05T10:07:50Z")

</div>

PEX works better inside the house where it’s warm. But if you put it in a cold garage, you need to wrap it up with insulation so it doesn’t freeze.

---

<div class="post-metadata">

**Author:** ![Tim\_curtis](https://home.renovation.reviews/user_avatar/home.renovation.reviews/tim_curtis/32/2766_2.png) [@Tim\_curtis](https://home.renovation.reviews/u/Tim_curtis)\
**Post date:** [August 5, 2025, 10:22am UTC](https://home.renovation.reviews/t/do-co2-r-744-hpwhs-pencil-out-in-very-cold-garages-versus-indoor-installations/19965/3 "2025-08-05T10:22:57Z")

</div>

I definitely agree with that 😃

It needs to be properly insulated to avoid freezing