Is Your Home Still Cold Even With the Heat Pump On? Here’s What to Do About It.

For many homeowners, especially in Southland, a heat pump is the go-to solution for staying warm in winter. They’re efficient, reliable, and designed to heat even large spaces. But what happens when your heat pump is on, maybe even running all day, and your home still feels cold?

If this sounds familiar, you’re not alone. In fact, it’s one of the most common issues we see in Southland homes. A heat pump can only do so much when the home itself is losing heat faster than the unit can supply it. The good news? There are clear reasons why this happens — and clear steps you can take to fix it.

Let’s break down the main causes and what you can do to finally enjoy a truly warm home this winter.

Your Home Is Losing Heat Faster Than the Heat Pump Can Replace It

Even the best heat pump, like those from Mitsubishi and Daikin, can’t compete with major heat loss. In Southland’s colder climate, heat escapes quickly through:

• Poor or ageing insulation
• Single-glazed or draughty windows
• Uninsulated walls
• Gaps around doors and frames
• Uninsulated hot water cylinders or pipes
• Underfloor draughts

If your home feels cold even when the heat pump is on, one or more of these is usually the problem.

What to do:

Start by checking the basics: ceiling insulation, underfloor insulation, wall insulation and windows. These areas alone account for most heat loss. If insulation isn’t up to standard, or missing entirely in some areas, your heat pump will always struggle.

A free home assessment from Awarua Synergy can pinpoint exactly where the heat is escaping and what improvements will make the biggest difference.  Our expert team will visit your home and chat through with you the best, and most cost efficient, solutions for your individual needs.

Your Heat Pump Is the Wrong Size for the Room

If the heat pump is too small, it will run constantly without ever getting the room truly warm. If it’s too large, it may short-cycle, heating unevenly and inefficiently.

What to do:

Make sure your unit is correctly sized for the space, ceiling height, insulation levels, and layout of your home. Our team can assess whether your current unit is suitable and recommend a correctly sized Mitsubishi or Daikin heat pump if needed.

Your Windows Are Letting Heat Escape

Windows are often the biggest source of heat loss — especially if your home still has single glazing or older aluminium joinery.

What to do:

Consider upgrading to modern double glazed windows and doors, such as Nulook systems designed for Southland’s climate. Double glazing dramatically reduces heat loss, helps reduce condensation on the windows, and makes your heat pump’s job far easier.

If replacement isn’t on the cards yet, even simple fixes like draught stoppers or thermal curtains can help in the short term. Install three-layer thermal curtains with pelmets, mounted high and extending to the floor, to fully insulate windows and prevent heat loss.

Your Home Has Moisture or Ventilation Issues

A damp home always feels colder. Moisture in the air pulls heat from your body and makes it much harder for your heat pump to warm the space.

What to do:

Good ventilation is key. A balanced home ventilation system can reduce moisture, improve air quality, and make your heat pump work more efficiently.

Signs you may have moisture problems:

• Condensation on windows
• Musty smells
• Damp walls or carpets
• Mould growth

If any of these sound familiar, addressing moisture is a must. Book a home assessment and our team can discuss the best ventilation system for your needs.

Your Heat Pump Needs Servicing

Even top-quality units need maintenance. Over time, filters clog, coils get dirty, and efficiency drops — which can make your home feel colder.

What to do:

Have your heat pump serviced annually to keep performance high and ensure efficient, reliable heating.  Book a heat pump service now!

Your Home Needs a Whole-Home Approach

Heating is just one part of the picture. Southland homes perform best when insulation, ventilation, glazing, and heating all work together.

A heat pump alone cannot fix:

• Heat loss
• Draughts
• Moisture
• Poor window performance
• Cold floors

But a whole-home energy solution can. Our expert team are here to help!

How Awarua Synergy Can Help

We specialise in helping Southland homes become truly warm, dry, and energy efficient — not just in one room, but throughout the whole home. Our free home assessments identify heat loss, insulation issues, ventilation needs, window performance, and more.

We work across Invercargill, Gore, Winton, Te Anau, Riverton, Bluff, and Mataura, offering trusted solutions including:

• Daikin and Mitsubishi heat pumps & servicing
• Insulation upgrades – ceiling, floor and wall insulation
• Double glazed windows
• Ventilation systems
• Hot water efficiency upgrades

If your home still feels cold — even with the heat pump running — it’s a sign that something else is missing. We’ll help you find the most effective fixes so your home stays warm all winter long.

Book your free home assessment today and discover what’s really holding your home back from being warm, cosy, and comfortable.