Viessmann Vitocal 200-A ie vs Vaillant aroTHERM pro: Which Heat Pump Is Right for You?

The Viessmann Vitocal 200-A ie brings Viessmann's engineering to a UK price point, and it's a real rival to the Vaillant aroTHERM pro. Neither wins across the board. Which suits you depends on your outdoor space, how much heat your home needs, and what else you plan to connect, so we've set this out by situation.

Both are R290 monobloc heat pumps from manufacturers with a long history of making heat pumps. We visited Viessmann's HQ for the Vitocal's UK launch: read our Vitocal 200-A ie launch write-up for the full story.

Geek Notes

Pick the aroTHERM pro if outdoor space is tight, if one unit needs to heat your whole home, or if noise matters most: Flexible Space Function lets it sit closer to boundaries and walls, its 11 kW model delivers more heat than the Vitocal's Type 12, and it's quieter at comparable sizes. Pick the Vitocal 200-A ie if your home needs more than one outdoor unit, because its cascade setup is simpler and cheaper, if you want Viessmann's 5-year guarantee extended up to 10 years with servicing, or if you're planning an all-Viessmann setup with solar, battery and EV charging.

What They Share

Both use R290 refrigerant. Both are app-controlled: ViCare for Viessmann, sensoCOMFORT for Vaillant. Both qualify for the Boiler Upgrade Scheme grant, and both work alongside a wide range of solar, battery and EV charging products.

Tight on Outdoor Space?

This is the biggest practical difference. R290 is a flammable refrigerant, so any R290 heat pump needs a clear exclusion zone around the outdoor unit, free of ignition sources like sockets, light switches and openable windows. On a standard installation that zone runs one metre in every direction. The aroTHERM pro's Flexible Space Function runs the fan continuously at low speed, even in standby, and disperses any leaked refrigerant, which shrinks the exclusion zone down to the area below the unit. That opens up corners, tight side returns and small gardens a standard R290 heat pump can't use. There's no equivalent feature on the Vitocal 200-A ie, so it needs the standard exclusion zone.

Edge: aroTHERM pro.

Heating a Larger Home?

It depends whether one outdoor unit can do the job. The type number on the Vitocal isn't its output: the Type 12, its largest model, delivers up to 10.2 kW at -2°C outside. The aroTHERM pro 11 kW delivers 12.65 kW at a 0°C design temperature with a 35°C flow, according to Vaillant's planning data. Those figures are at slightly different outdoor temperatures, and the pro would deliver a little less at -2°C, but it still gives you more from a single unit.

Once your home needs more heat than one unit can give, Viessmann wins hands down. Up to four Vitocal 200-A ie outdoor units can run off a single controller, and the cascade integration is simple and cheap to set up.

Edge: aroTHERM pro if one unit is enough; Vitocal 200-A ie if you need two or more.

Planning Solar, a Battery or an EV Charger?

Both heat pumps can be used alongside lots of solar, battery and EV charging products, so neither locks you in. The Vitocal only pulls ahead if you're going with Viessmann products: Viessmann's One Base platform runs a Viessmann heat pump, solar panels, battery and EV charger as one system in the ViCare app, with dynamic tariff support built in.

Edge: Vitocal 200-A ie, but only for an all-Viessmann setup. Otherwise, it's even.

How Long Is the Guarantee?

Viessmann backs the Vitocal 200-A ie with a 5-year guarantee as standard, and extends it up to 10 years if you keep it serviced regularly through Viessmann. Vaillant's standard guarantee on the aroTHERM pro is 2 years. Buy it through Heat Geek, though, and you get an exclusive 5-year guarantee that's only available through us.

Edge: Vitocal 200-A ie, thanks to the extension up to 10 years with servicing.

How Proven Is It in the UK?

Neither manufacturer is new to making heat pumps; both have long manufacturing histories. Vaillant's aroTHERM plus has been installed across the UK for years, and the aroTHERM pro is very similar to it (see our aroTHERM pro vs plus comparison). Viessmann has also made heat pumps for a long time, and its high-end and larger heat pumps have been installed in the UK for years.

What's new is this specific product. The Vitocal 200-A ie is new to the UK, new to Heat Geek and new to every installer fitting it. That doesn't make it a bad heat pump at all. As with anything new, we'll keep installing it and put it through rigorous testing on real-life installs, like we always do. Viessmann is a quality manufacturer, so we don't anticipate major problems.

Edge: aroTHERM pro for now, because it's so close to the long-proven plus.

Does Noise Matter?

At comparable sizes, the aroTHERM pro is the quieter unit: 49 dB(A) for the 7 kW against 53 dB(A) for the Vitocal Type 8 (ErP sound power). If the outdoor unit will sit near a bedroom window or a neighbour's boundary, that's worth weighing up.

Edge: aroTHERM pro.

The Comparison at a Glance

Our View

Neither heat pump wins across the board. The aroTHERM pro suits tight outdoor spaces, homes one unit can heat, and anywhere noise matters, and it builds on the long UK history of the very similar plus. The Vitocal 200-A ie suits larger homes that need more than one unit, buyers who want a guarantee of up to 10 years with servicing, and anyone planning an all-Viessmann energy setup. That's #nopanacea in practice.

For full specifications, see our Vitocal 200-A ie and aroTHERM pro product pages.

The only way to know which is right for your home is a proper heat loss assessment and a look at your outdoor space. That's what a Heat Geek Design Consultation is for. Book one and we'll give you a straight recommendation.