エアコンを交換しますか?このガイドは、最適なシステムを選択するのに役立ちます

エアコンの買い替え時期は？新しい HVAC 機器を選択するプロセスは複雑に思えるかもしれません。多くの人にとっては、どの種類の車を購入するかを決めるのと同じように、威圧感さえ感じます.

しかし、そうである必要はありません。さまざまな HVAC オプションについて知れば知るほど、ニーズと予算に合ったシステムを選択できる可能性が高くなります。

まず最初に:新しいエアコンが本当に必要ですか?

多くの住宅所有者は、次の場合にエアコンをアップグレードする必要があると考えています。

• 夏は暑すぎる
• 特定の部屋を十分に冷やすことができない
• 室内の湿度が高い
• 夏の光熱費が高く、その理由がわからない

しかし、これらの問題はいずれも、必ずしも新しい機器の必要性を示しているわけではありません。これらの問題の多くは、メンテナンスの欠如、ダクトの漏れ、不十分な断熱材、家中の空気漏れが原因である可能性があります.

つまり、HVAC に問題がない可能性があります。ホーム パフォーマンスに問題がある可能性があります。

一方、AC を交換する必要があるのは次の場合です。

• 10 年以上前のもので、以前のようには機能しません。
• システムは頻繁に高価な修理が必要です。
• 空気漏れを止めたり、断熱材をアップグレードしたり、ダクトを密閉したりしても、まだ快適さの問題があります。
• あなたの現在のシステムは完全に崩壊しています

上記の 2 つ以上が当てはまる場合、ニヤリと笑って古い不格好な機器に耐えるよりも、交換する方がおそらく理にかなっています。

ステップ 1:システムのサイズを適切に設定します。

わかりました。快適さと効率を最適化する唯一の方法は、エアコンを交換することだと確信しています。どこから始めますか?

現在のシステムと同じサイズの新しいシステムの見積もりを依頼したくなるかもしれませんが、それは実際には良い考えではありません。まず、大型のエアコンをずっと使用している可能性が高いです。 1 つの特大ユニットを別の特大ユニットに交換しても、できません 快適さの問題を解決しましょう!

オーバーサイジングを避けるために、新しいシステムを見積もるすべての請負業者は、家で手動 J 負荷計算を実行して、新しい AC の適切なトン数を決定する必要があります。 気候帯と家の面積の経験則ではうまくいきません。 現在のシステムが大きすぎる場合、これらの「信頼できる」経験則が実際に問題になる可能性があります!

Another reason to perform a load calculation is that the attributes of your home might have changed since your last HVAC upgrade. Maybe you sealed up some air leaks, increased attic insulation, or otherwise improved your home's energy performance. If that's the case, you might get by with a smaller AC than before.

Long story short:The Manual J load calculation is necessary. Any HVAC contractor who says otherwise is not the contractor for you.

Step 2:Understand SEER.

When it comes to efficiency, nearly any air conditioner available today will be more efficient than what you're replacing. A unit's SEER, or "seasonal energy efficiency ratio" where a higher number indicates a more efficient unit, can help you understand how efficiently a particular AC will operate.

But only to a point. You see, using SEER alone to determine your AC purchase decision is problematic.

For one thing, 14 SEER is the minimum these days. If you're replacing an old system, you're automatically getting an enormous efficiency boost, no matter what! What's more, a unit's SEER only speaks to one aspect of a system's overall efficiency.

SEER reflects the efficiency of an air conditioner while it's operating , and that's important. But it doesn't reflect how you use the system in your home.

Step 3:Prioritize your air handler/furnace selection over SEER.

The type of furnace/air handler, or blower, you choose is more important for efficiency and comfort than an air conditioner's SEER. Now that you understand the basics of SEER (higher number =better), consider the benefit of prioritizing air handler type over SEER for your next air conditioner.

Let's say you're looking at two different systems:

• 16 SEER air conditioner with a single speed air handler
• 15 SEER air conditioner with a variable speed air handler

Of the two, the 16 SEER unit with the single speed air handler will actually lead to less comfortable conditions than the 15 SEER unit, even though the efficiency rating is higher. It might even be more expensive to operate.

なんで？ When a variable air flow system is cooling your home, it removes 3 to 4 times more moisture than a standard system with on/off air flow. Basically, you'll feel more comfortable at higher temperatures. You'll also spend less on energy, even though your system has a lower SEER.

A single speed air handler also costs more to operate than an air handler that runs more continuously. It's quieter. It allows for better filtration and indoor air quality. It's just better!

Opting for a thermostat with dehumidification control in addition to a variable speed blower is a great way to further mitigate comfort deficiencies and temper a system's tendency to cycle on and off. It turns the system on via a humidity call, running at a lower speed for longer intervals to better dehumidify the home. Installing one also functionally increases your unit's SEER. For instance, a 14 SEER unit with dehumidification control actually operates at around 15 SEER.

Here's the bottom line:If your budget allows for either a higher SEER or a variable speed air handler, use your money for the air handler. The specs aren't as efficient, but the way it operates will save you money and increase comfort.

Step 4:Opt for a higher SEER.

If you've chosen a variable speed air handler and still have money in your budget, now's the time to get the highest SEER you can afford for an outdoor unit. After making the optimal air handler selection, a unit's SEER really starts to make a difference.

Speaking of outdoor units…

Step 5:Decide among single stage, two stage, and variable speed compressors.

By now, you've identified a properly sized system and decided to prioritize air handler speed over SEER when choosing equipment. What's next?

This is the point at which you choose a compressor type. You can opt for a single stage, two stage, or variable speed compressor. Single stage is the least expensive (and least efficient) and variable speed is the most expensive (and most efficient).

If you've already decided to opt for a variable speed air handler and you have the budget for a two stage or variable speed compressor, that's the way to go. You want your system to cycle as infrequently as possible! Two stage and variable speed compressors already have high SEER by default, so you're set when it comes to efficiency.

Basically, settling for a single stage compressor with a single speed air handler gives you a system that cuts on and off all the time . It's like owning a car that only travels at 0 mph and 65 mph with nothing in between.

Even at 20 SEER, that's not an ideal arrangement.

When choosing a new AC, following the proper sequence makes a difference.

To recap, here are the proper steps to follow when selecting new air conditioning equipment:

• Size the system properly: Performing a Manual J load calculation (or having your contractor perform one) is the only way to go.
• Understand SEER, but know its limitations: A higher SEER is more efficient, but the way an AC operates matters more than its SEER.
• Prioritize air handler type over SEER: If you've got the budget to purchase an AC with a higher SEER, consider a variable speed air handler instead.
• Choose according to SEER: After opting for a variable speed air handler, SEER starts to make a big difference in overall system efficiency.
• Choose a compressor type: Two stage or variable speed compressors are the most efficient options and provide the most consistent comfort. Assuming there's room in your budget, choose one of these compressors over a single stage unit.

By adhering to the above sequence, you won't fall victim to many common pitfalls of AC replacement. You'll end up with the most effective, properly sized system for the money.

You'll probably lower your utility bills, too.