Drew Tozer
@drewtozer.bsky.social
Installing heat pumps for comfortable, healthy, sustainable homes in Toronto, Canada.
Every HVAC contractor is a climate company.
https://foundryheatpumps.ca
Every HVAC contractor is a climate company.
https://foundryheatpumps.ca
Rip out an old and busted furnace.
Install a fully electric heat pump. New hotness.
The before and after is oddly satisfying.
Install a fully electric heat pump. New hotness.
The before and after is oddly satisfying.
June 10, 2025 at 1:29 PM
Rip out an old and busted furnace.
Install a fully electric heat pump. New hotness.
The before and after is oddly satisfying.
Install a fully electric heat pump. New hotness.
The before and after is oddly satisfying.
A single-stage 6-ton oil furnace...that's 4x too big.
On the coldest week of the year, it'll run 15-min per hour.
This is where heat pumps shine. It's the only HVAC system that can be properly sized to match the heating needs of this house.
On the coldest week of the year, it'll run 15-min per hour.
This is where heat pumps shine. It's the only HVAC system that can be properly sized to match the heating needs of this house.
June 3, 2025 at 2:00 PM
A single-stage 6-ton oil furnace...that's 4x too big.
On the coldest week of the year, it'll run 15-min per hour.
This is where heat pumps shine. It's the only HVAC system that can be properly sized to match the heating needs of this house.
On the coldest week of the year, it'll run 15-min per hour.
This is where heat pumps shine. It's the only HVAC system that can be properly sized to match the heating needs of this house.
Even in tight spaces, you can do a big return air drop and a thick filter.
If you install premium equipment poorly, it'll perform poorly and fail early. Increasing the size of the return air drop and filter surface area can significantly improve heat pump performance. The goal is happy homeowners.
If you install premium equipment poorly, it'll perform poorly and fail early. Increasing the size of the return air drop and filter surface area can significantly improve heat pump performance. The goal is happy homeowners.
April 30, 2025 at 2:25 PM
Even in tight spaces, you can do a big return air drop and a thick filter.
If you install premium equipment poorly, it'll perform poorly and fail early. Increasing the size of the return air drop and filter surface area can significantly improve heat pump performance. The goal is happy homeowners.
If you install premium equipment poorly, it'll perform poorly and fail early. Increasing the size of the return air drop and filter surface area can significantly improve heat pump performance. The goal is happy homeowners.
A homeowner 1,700+ km from me is using the book as an easy first step to learn about right-sized HVAC and home performance before upgrading.
I have nothing to sell him, but it increases the odds that he has a remarkable experience with heat pumps and pushes the electrification movement forward.
I have nothing to sell him, but it increases the odds that he has a remarkable experience with heat pumps and pushes the electrification movement forward.
April 9, 2025 at 12:30 PM
A homeowner 1,700+ km from me is using the book as an easy first step to learn about right-sized HVAC and home performance before upgrading.
I have nothing to sell him, but it increases the odds that he has a remarkable experience with heat pumps and pushes the electrification movement forward.
I have nothing to sell him, but it increases the odds that he has a remarkable experience with heat pumps and pushes the electrification movement forward.
This contractor has a 90% failure rate on heat pumps.
Heat pumps require more expertise and attention-to-detail to install properly. Traditional furnaces and ACs were comparatively simple to install, so contractor quality didn't matter as much. But it matters with heat pumps.
Heat pumps require more expertise and attention-to-detail to install properly. Traditional furnaces and ACs were comparatively simple to install, so contractor quality didn't matter as much. But it matters with heat pumps.
April 3, 2025 at 3:55 PM
This contractor has a 90% failure rate on heat pumps.
Heat pumps require more expertise and attention-to-detail to install properly. Traditional furnaces and ACs were comparatively simple to install, so contractor quality didn't matter as much. But it matters with heat pumps.
Heat pumps require more expertise and attention-to-detail to install properly. Traditional furnaces and ACs were comparatively simple to install, so contractor quality didn't matter as much. But it matters with heat pumps.
My book (Feel-Good Homes) launched!
I'm giving away a Kindle to celebrate.
Everyone deserves a comfortable, healthy, sustainable home.
But electrification and home performance are hard.
So, "Feel-Good Homes" is a simple first step.
I made it short and conversational.
It's for average homeowners.
I'm giving away a Kindle to celebrate.
Everyone deserves a comfortable, healthy, sustainable home.
But electrification and home performance are hard.
So, "Feel-Good Homes" is a simple first step.
I made it short and conversational.
It's for average homeowners.
March 25, 2025 at 12:32 PM
My book (Feel-Good Homes) launched!
I'm giving away a Kindle to celebrate.
Everyone deserves a comfortable, healthy, sustainable home.
But electrification and home performance are hard.
So, "Feel-Good Homes" is a simple first step.
I made it short and conversational.
It's for average homeowners.
I'm giving away a Kindle to celebrate.
Everyone deserves a comfortable, healthy, sustainable home.
But electrification and home performance are hard.
So, "Feel-Good Homes" is a simple first step.
I made it short and conversational.
It's for average homeowners.
"You don't need people's opinions on a fact."
Science doesn't care about opinions.
John Oliver’s original video was about climate change.
But there’s been a rise of "do your own research".
So now it applies to more topics than ever.
Above political ideology, I stand with science.
Science doesn't care about opinions.
John Oliver’s original video was about climate change.
But there’s been a rise of "do your own research".
So now it applies to more topics than ever.
Above political ideology, I stand with science.
February 14, 2025 at 1:48 PM
"You don't need people's opinions on a fact."
Science doesn't care about opinions.
John Oliver’s original video was about climate change.
But there’s been a rise of "do your own research".
So now it applies to more topics than ever.
Above political ideology, I stand with science.
Science doesn't care about opinions.
John Oliver’s original video was about climate change.
But there’s been a rise of "do your own research".
So now it applies to more topics than ever.
Above political ideology, I stand with science.
🔴 An oversized furnace doesn't let the house get cold, ever.
🟡 That comes at the expense of comfort.
🟢 Because comfort is solved by right-sized HVAC.
➡️ So, if you replace an old, oversized furnace with a new, oversized furnace, don't be surprised when you have the same comfort problems.
🟡 That comes at the expense of comfort.
🟢 Because comfort is solved by right-sized HVAC.
➡️ So, if you replace an old, oversized furnace with a new, oversized furnace, don't be surprised when you have the same comfort problems.
February 10, 2025 at 6:09 PM
🔴 An oversized furnace doesn't let the house get cold, ever.
🟡 That comes at the expense of comfort.
🟢 Because comfort is solved by right-sized HVAC.
➡️ So, if you replace an old, oversized furnace with a new, oversized furnace, don't be surprised when you have the same comfort problems.
🟡 That comes at the expense of comfort.
🟢 Because comfort is solved by right-sized HVAC.
➡️ So, if you replace an old, oversized furnace with a new, oversized furnace, don't be surprised when you have the same comfort problems.
Heat pumps are ACs that can heat and cool.
Central units look like a furnace/AC.
A heat pump includes both indoor and outdoor units.
The indoor air handler (fan) looks like a furnace.
And the outdoor unit is like a traditional AC.
It helps to explain this to homeowners.
Heat pumps look familiar.
Central units look like a furnace/AC.
A heat pump includes both indoor and outdoor units.
The indoor air handler (fan) looks like a furnace.
And the outdoor unit is like a traditional AC.
It helps to explain this to homeowners.
Heat pumps look familiar.
February 7, 2025 at 8:06 PM
Heat pumps are ACs that can heat and cool.
Central units look like a furnace/AC.
A heat pump includes both indoor and outdoor units.
The indoor air handler (fan) looks like a furnace.
And the outdoor unit is like a traditional AC.
It helps to explain this to homeowners.
Heat pumps look familiar.
Central units look like a furnace/AC.
A heat pump includes both indoor and outdoor units.
The indoor air handler (fan) looks like a furnace.
And the outdoor unit is like a traditional AC.
It helps to explain this to homeowners.
Heat pumps look familiar.
‘Cold snap anxiety’ is a real thing.
It's ‘range anxiety’ for heat pumps.
I'm officially coining the term.
"How do you get heat from cold air?"
"I'm keeping my gas furnace, just in case."
"I heard heat pumps don't work below freezing."
These are real concerns for homeowners. 1/3 🧵
It's ‘range anxiety’ for heat pumps.
I'm officially coining the term.
"How do you get heat from cold air?"
"I'm keeping my gas furnace, just in case."
"I heard heat pumps don't work below freezing."
These are real concerns for homeowners. 1/3 🧵
February 5, 2025 at 1:48 PM
‘Cold snap anxiety’ is a real thing.
It's ‘range anxiety’ for heat pumps.
I'm officially coining the term.
"How do you get heat from cold air?"
"I'm keeping my gas furnace, just in case."
"I heard heat pumps don't work below freezing."
These are real concerns for homeowners. 1/3 🧵
It's ‘range anxiety’ for heat pumps.
I'm officially coining the term.
"How do you get heat from cold air?"
"I'm keeping my gas furnace, just in case."
"I heard heat pumps don't work below freezing."
These are real concerns for homeowners. 1/3 🧵
Humans are comfortable around 20–27°C.
And that's why heat pumps aren't intuitive.
We think about temperatures as either Celsius or Fahrenheit.
And cold snaps can be negative values on those scales.
So we tend to assume that cold air has no energy.
Thread 1/4 🧵
And that's why heat pumps aren't intuitive.
We think about temperatures as either Celsius or Fahrenheit.
And cold snaps can be negative values on those scales.
So we tend to assume that cold air has no energy.
Thread 1/4 🧵
January 31, 2025 at 1:47 PM
Humans are comfortable around 20–27°C.
And that's why heat pumps aren't intuitive.
We think about temperatures as either Celsius or Fahrenheit.
And cold snaps can be negative values on those scales.
So we tend to assume that cold air has no energy.
Thread 1/4 🧵
And that's why heat pumps aren't intuitive.
We think about temperatures as either Celsius or Fahrenheit.
And cold snaps can be negative values on those scales.
So we tend to assume that cold air has no energy.
Thread 1/4 🧵
I talk to homeowners every day.
And it's the same conversation.
So, I compiled those explanations, stories, questions, and objections into ‘Feel-Good Homes’ (available March 25 on Amazon).
It's a practical guide to transforming an average house into a comfortable, healthy, sustainable home.
And it's the same conversation.
So, I compiled those explanations, stories, questions, and objections into ‘Feel-Good Homes’ (available March 25 on Amazon).
It's a practical guide to transforming an average house into a comfortable, healthy, sustainable home.
January 30, 2025 at 8:35 PM
I talk to homeowners every day.
And it's the same conversation.
So, I compiled those explanations, stories, questions, and objections into ‘Feel-Good Homes’ (available March 25 on Amazon).
It's a practical guide to transforming an average house into a comfortable, healthy, sustainable home.
And it's the same conversation.
So, I compiled those explanations, stories, questions, and objections into ‘Feel-Good Homes’ (available March 25 on Amazon).
It's a practical guide to transforming an average house into a comfortable, healthy, sustainable home.
Imagine a car that can't drive slower than 100 km/h.
That's what a gas furnace does.
Welcome to your new car!
You tap the pedal and your head snaps back.
It jolts into 'full acceleration', trying to go from zero to 100.
Almost immediately, you're driving 70 km/h on a 50 road.
Thread 1/5 🧵
That's what a gas furnace does.
Welcome to your new car!
You tap the pedal and your head snaps back.
It jolts into 'full acceleration', trying to go from zero to 100.
Almost immediately, you're driving 70 km/h on a 50 road.
Thread 1/5 🧵
January 29, 2025 at 1:56 PM
Imagine a car that can't drive slower than 100 km/h.
That's what a gas furnace does.
Welcome to your new car!
You tap the pedal and your head snaps back.
It jolts into 'full acceleration', trying to go from zero to 100.
Almost immediately, you're driving 70 km/h on a 50 road.
Thread 1/5 🧵
That's what a gas furnace does.
Welcome to your new car!
You tap the pedal and your head snaps back.
It jolts into 'full acceleration', trying to go from zero to 100.
Almost immediately, you're driving 70 km/h on a 50 road.
Thread 1/5 🧵
I wish air-to-air heat pumps were this cool.
Hydronics definitely win on ‘cool factor’.
Old houses with radiators are the toughest to electrify. I wonder if an electric boiler paired with minisplits is the way forward—add a ventilating dehumidifier for better IAQ and dehumidification.
Hydronics definitely win on ‘cool factor’.
Old houses with radiators are the toughest to electrify. I wonder if an electric boiler paired with minisplits is the way forward—add a ventilating dehumidifier for better IAQ and dehumidification.
January 28, 2025 at 2:09 PM
I wish air-to-air heat pumps were this cool.
Hydronics definitely win on ‘cool factor’.
Old houses with radiators are the toughest to electrify. I wonder if an electric boiler paired with minisplits is the way forward—add a ventilating dehumidifier for better IAQ and dehumidification.
Hydronics definitely win on ‘cool factor’.
Old houses with radiators are the toughest to electrify. I wonder if an electric boiler paired with minisplits is the way forward—add a ventilating dehumidifier for better IAQ and dehumidification.
Would you buy an EV that only works in the summer?
No? Then why buy AC instead of a heat pump…
Canadians only use ACs for a few months each year.
And the rest of the time it just sits there, waiting.
There's no need to own two separate systems.
Heat pumps are ACs that can heat and cool.
No? Then why buy AC instead of a heat pump…
Canadians only use ACs for a few months each year.
And the rest of the time it just sits there, waiting.
There's no need to own two separate systems.
Heat pumps are ACs that can heat and cool.
January 27, 2025 at 1:48 PM
Would you buy an EV that only works in the summer?
No? Then why buy AC instead of a heat pump…
Canadians only use ACs for a few months each year.
And the rest of the time it just sits there, waiting.
There's no need to own two separate systems.
Heat pumps are ACs that can heat and cool.
No? Then why buy AC instead of a heat pump…
Canadians only use ACs for a few months each year.
And the rest of the time it just sits there, waiting.
There's no need to own two separate systems.
Heat pumps are ACs that can heat and cool.
Today is the saddest day of the year. 😔
Did you know that heat pumps can help? 🌦️
Right-sized HVAC leads to better homeowner experiences.
For most Canadians, 'right-sized' means heat pumps.
They're the path to comfortable, healthy homes.
Thread 1/6 🧵
Did you know that heat pumps can help? 🌦️
Right-sized HVAC leads to better homeowner experiences.
For most Canadians, 'right-sized' means heat pumps.
They're the path to comfortable, healthy homes.
Thread 1/6 🧵
January 20, 2025 at 2:19 PM
Today is the saddest day of the year. 😔
Did you know that heat pumps can help? 🌦️
Right-sized HVAC leads to better homeowner experiences.
For most Canadians, 'right-sized' means heat pumps.
They're the path to comfortable, healthy homes.
Thread 1/6 🧵
Did you know that heat pumps can help? 🌦️
Right-sized HVAC leads to better homeowner experiences.
For most Canadians, 'right-sized' means heat pumps.
They're the path to comfortable, healthy homes.
Thread 1/6 🧵
Heat pumps can make dangerous ice patches.
The defrost cycles clears the outdoor unit from ice and snow, but the melt drips to the ground and can refreeze.
At Foundry Heat Pumps, we build a wood frame and fill it with rocks. It solves the ice problem—and who says a heat pump can’t look great? 🤔
The defrost cycles clears the outdoor unit from ice and snow, but the melt drips to the ground and can refreeze.
At Foundry Heat Pumps, we build a wood frame and fill it with rocks. It solves the ice problem—and who says a heat pump can’t look great? 🤔
January 19, 2025 at 4:40 PM
Heat pumps can make dangerous ice patches.
The defrost cycles clears the outdoor unit from ice and snow, but the melt drips to the ground and can refreeze.
At Foundry Heat Pumps, we build a wood frame and fill it with rocks. It solves the ice problem—and who says a heat pump can’t look great? 🤔
The defrost cycles clears the outdoor unit from ice and snow, but the melt drips to the ground and can refreeze.
At Foundry Heat Pumps, we build a wood frame and fill it with rocks. It solves the ice problem—and who says a heat pump can’t look great? 🤔
A new rebate program is launching in Ontario. 🎉
PSA: But don't just chase the money. 🤔
What problem are you trying to solve in your house?
It's important to pick the *right* solution.
Not just the eligible one.
PSA: But don't just chase the money. 🤔
What problem are you trying to solve in your house?
It's important to pick the *right* solution.
Not just the eligible one.
January 7, 2025 at 5:32 PM
A new rebate program is launching in Ontario. 🎉
PSA: But don't just chase the money. 🤔
What problem are you trying to solve in your house?
It's important to pick the *right* solution.
Not just the eligible one.
PSA: But don't just chase the money. 🤔
What problem are you trying to solve in your house?
It's important to pick the *right* solution.
Not just the eligible one.
Right-sized HVAC is still wrong, sometimes. ⛔
The range of outdoor temps is too wide. 😬
Equipment is sized for the 1% coldest hours of the year.
That metric is called the 99% design temperature.
Only 3-4 days per year (on avg) are colder.
Thread 1/7 🧵
The range of outdoor temps is too wide. 😬
Equipment is sized for the 1% coldest hours of the year.
That metric is called the 99% design temperature.
Only 3-4 days per year (on avg) are colder.
Thread 1/7 🧵
January 7, 2025 at 1:56 PM
Right-sized HVAC is still wrong, sometimes. ⛔
The range of outdoor temps is too wide. 😬
Equipment is sized for the 1% coldest hours of the year.
That metric is called the 99% design temperature.
Only 3-4 days per year (on avg) are colder.
Thread 1/7 🧵
The range of outdoor temps is too wide. 😬
Equipment is sized for the 1% coldest hours of the year.
That metric is called the 99% design temperature.
Only 3-4 days per year (on avg) are colder.
Thread 1/7 🧵
Callbacks kill profitability, so contractors found a solution. 💡
From their point of view, oversizing HVAC is great. 👀
It eliminates the risk of a furnace being too small. 💥
1/4 🧵
From their point of view, oversizing HVAC is great. 👀
It eliminates the risk of a furnace being too small. 💥
1/4 🧵
January 3, 2025 at 5:00 PM
Callbacks kill profitability, so contractors found a solution. 💡
From their point of view, oversizing HVAC is great. 👀
It eliminates the risk of a furnace being too small. 💥
1/4 🧵
From their point of view, oversizing HVAC is great. 👀
It eliminates the risk of a furnace being too small. 💥
1/4 🧵
➡️ Because of politics, electricity emissions will soon be 7-8x higher than the 2017 low. Embracing high-carbon, centralized generation was a choice.
But renewables are the cheapest energy in history, and economics will drive the grid to solar, wind, and batteries over time. ⛅️ 7/7
But renewables are the cheapest energy in history, and economics will drive the grid to solar, wind, and batteries over time. ⛅️ 7/7
December 31, 2024 at 3:36 PM
➡️ Because of politics, electricity emissions will soon be 7-8x higher than the 2017 low. Embracing high-carbon, centralized generation was a choice.
But renewables are the cheapest energy in history, and economics will drive the grid to solar, wind, and batteries over time. ⛅️ 7/7
But renewables are the cheapest energy in history, and economics will drive the grid to solar, wind, and batteries over time. ⛅️ 7/7
4/ Literally, electricity generation varies by the minute. 🔌
Everyone talks about average grid emissions.
Comparing across provinces and states.
But hourly differences matter too.
Everyone talks about average grid emissions.
Comparing across provinces and states.
But hourly differences matter too.
December 31, 2024 at 3:36 PM
4/ Literally, electricity generation varies by the minute. 🔌
Everyone talks about average grid emissions.
Comparing across provinces and states.
But hourly differences matter too.
Everyone talks about average grid emissions.
Comparing across provinces and states.
But hourly differences matter too.
I spent less on hot water than you. 💰
And I did it with resistance heat. ⚡️
The trick is to take advantage of off-peak power. 💡
1/7 🧵
And I did it with resistance heat. ⚡️
The trick is to take advantage of off-peak power. 💡
1/7 🧵
December 31, 2024 at 3:36 PM
I spent less on hot water than you. 💰
And I did it with resistance heat. ⚡️
The trick is to take advantage of off-peak power. 💡
1/7 🧵
And I did it with resistance heat. ⚡️
The trick is to take advantage of off-peak power. 💡
1/7 🧵
Grid reliability isn’t homeowners’ responsibility. It should have no impact on your personal decision to electrify.
If you wanted to buy an AC or hot tub, nobody argues with you about the grid.
It’s an anti-heat pump talking point — try it as such.
If you wanted to buy an AC or hot tub, nobody argues with you about the grid.
It’s an anti-heat pump talking point — try it as such.
December 26, 2024 at 7:54 PM
Grid reliability isn’t homeowners’ responsibility. It should have no impact on your personal decision to electrify.
If you wanted to buy an AC or hot tub, nobody argues with you about the grid.
It’s an anti-heat pump talking point — try it as such.
If you wanted to buy an AC or hot tub, nobody argues with you about the grid.
It’s an anti-heat pump talking point — try it as such.
"I don't care about the planet." 🪐
That's how people feel about electrification. 🤔
But electrification isn't just about climate change.
It's a movement to improve our quality of life.
By spending time in remarkable places.
I electrified for better family comfort, health, and safety. 👨👩👦👦
🧵 1/3
That's how people feel about electrification. 🤔
But electrification isn't just about climate change.
It's a movement to improve our quality of life.
By spending time in remarkable places.
I electrified for better family comfort, health, and safety. 👨👩👦👦
🧵 1/3
December 24, 2024 at 7:08 PM
"I don't care about the planet." 🪐
That's how people feel about electrification. 🤔
But electrification isn't just about climate change.
It's a movement to improve our quality of life.
By spending time in remarkable places.
I electrified for better family comfort, health, and safety. 👨👩👦👦
🧵 1/3
That's how people feel about electrification. 🤔
But electrification isn't just about climate change.
It's a movement to improve our quality of life.
By spending time in remarkable places.
I electrified for better family comfort, health, and safety. 👨👩👦👦
🧵 1/3