Purewell Variheat mk2 condensing cast iron boiler

Available in 5 condensing models with outputs (@50/30°C) of 70, 95, 110, 140 and 180 kW.
The only cast iron condensing commercial boiler that is compliant with the Energy related Products Directive (ErP) available in the UK.

Product information

Proven reliability with a 10-year heat exchanger warranty
The only cast iron condensing commercial boiler that is compliant with the Energy related Products Directive (ErP) available in the UK.
Built in boiler sequence controls capable of controlling up to 16 boiler modules and hot water circuits
Easy access for servicing with quick to remove front cover hooks
Full spark ignitor enables servicing without the need to remove the whole burner
Low NOx performance (<40mg/kWh, European Class 6)
Non complicated design means the Purewell Variheat mk2 is easy to operate & maintain, saving on time and money
Highly efficient offering up to 96% gross seasonal efficiency, reducing carbon emissions and saving the end user money on fuel bills
Sits on same footprint as many traditional and atmospheric cast iron boilers reducing space concerns
Easy access to plant room as the Purewell Variheat mk2 fits through a standard doorway
Can be disassembled for plant rooms with difficult access
Tolerant of existing heating systems making the Purewell Variheat mk2 the perfect choice when replacing old atmospheric boilers
Operates in sealed and open vented heating systems (you can read about the differences of Sealed 'v' Open Vented heating systems here)
Suitable for use with LPG Air for installation in the Channel Islands
BIM objects available to assist in design and management

Ideal uses/applications

Easy fit replacement for refurbishment projects.
Medium sized commercial and public buildings including schools, care homes, hotels, churches and retail units.
Smaller commercial and public buildings including community schools, care homes, hotels, churches and retail units.
Locations with substantial and continuous heating load including hospitals, care homes and hotels.
Ideal replacement for atmospheric boilers.

Optional extras

Reverse return header kit available for:

2 boiler installation
3 boiler installation
4 boiler installation ( 2 x 2 boiler installation kit)
Flues available
Choose from a wide range of service contracts to help maintain optimum performance.
Book commissioning at the same time as placing your order for improved warranty terms.

Energy

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Building regulations - seasonal efficiency	(%) gross	95.3	95.6	95.8	95.7	94.6
ErP efficiency rating (modules ≤ 70 kW only)		A	N/A	N/A	N/A	N/A
Boiler output (non-condensing) mean 70°C - max	kW	63.5	86.3	99.8	134.4	172.8
Boiler output (non-condensing) mean 70°C - min	kW	21.2	28.8	33.3	44.8	50.3
Boiler output (condensing) mean 40°C - max	kW	70	95	110	140	180
Boiler output (condensing) mean 40°C - min	kW	23.3	31.67	36.37	46.67	53.0
Gross boiler input - max	kW	72.2	98.4	115	151.3	194.6
Gross boiler input - min	kW	24.1	26.7	38.3	50.4	56.6
Net boiler input - max	kW	65	88.6	103.5	136.3	175.2
Net boiler input - min	kW	21.7	29.6	34.5	45.4	51.0

Water

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Water content	litres	8	8	8	11	11
System design flow rate @ 20°C ∆T rise	l/s	0.8	1.1	1.3	1.7	2.1
Water side pressure loss @ 20°C ∆T rise	mbar	32	52	72	134	221
System design flow rate @ 11°C ∆T rise	l/s	1.5	2.1	2.4	3	3.9
Water side pressure loss @ 11°C ∆T rise	mbar	96	176	244	442	731
Maximum water pressure	bar g	6	6	6	6	6

Gas

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Gas flow rate natural gas (G20) - max	m3/hr	6.9	9.4	10.9	14.4	18.5
Nominal inlet pressure natural gas (G20) - max	mbar	20	20	20	20	20
Maximum gas inlet pressure natural gas (G20)	mbar	25	25	25	25	25

Flue

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Flue Gas Flow Rate@ 15°C, 9.5% CO2	m3/hr	86	117	137	180	232
Approx. flue gas temperature @ 50/30°C	°C	40	40	45	50	50
Approx. flue gas temperature @ 80/60°C	°C	60	60	65	70	75
Pressure at boiler flue spigot @full load	Pa	100	100	100	100	100
Dry NOx emission*	mg/kWh	21.3	31.1	39.1	32	37.8

Connection

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Water flow/return connections	inches	R2”	R2”	R2”	R2”	R2”
Gas inlet connection pipe thread size	inches	R1”	R1”	R1”	R1”	R1”
Nominal flue diameter (I/D)	mm	150	150	150	150	150

Electrics

	Units	PV70c	PV95c	PV110c	PV140c	PV180c
Electrical supply		230 V 1 Ph 50 Hz	230 V 1 Ph 50 Hz	230 V 1 Ph 50 Hz	230 V 1 Ph 50 Hz	230 V 1 Ph 50 Hz
Power consumption @ max	W	94	94	94	207	207
IEC power outlet power consumption @ max	W	460	460	460	460	460
Start current and run current	Amp	0.54	0.54	0.54	0.6	0.6
Approx shipping weight	kg	195	195	195	250	250
Noise emission @1 m and @maximum boiler modulation	Max dB (A)	53	53	53	65	65
CO2 (±0.25%) - max	%	9.5	9.5	9.5	9.5	9.5
CO2 (±0.25%) - min	%	9.5	9.5	9.5	8.5	8.5
*0% excess oxygen, dry air free, European Class 6

Brochures

Hydraulic Schematics

purewell-variheat-mk2-rev-b-hydraulic-schemes

Installation And Servicing

User Guides

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CAD
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sb08204-a-variheat-mk2-2d-layout-3-boilers
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Frequently Asked Questions

Can the Purewell Variheat boiler run on an open vented system?

Yes. The Purewell Variheat boiler is able to operate on an open vented heating system.

We would advise compliance with minimum pressure requirements at boiler, reference guidance note INDG436 (Health and Safety Executive).

Open vent and cold feed pipes must be installed correctly and in compliance with BS6644. You can refer to the installer guide for detailed information on Open Vent and Cold Feed pipes.

However, Hamworthy recommends the use of sealed heating systems, where possible.

If you want to know the difference between a sealed system and open vented system, find out more here.

Can the Purewell Variheat boiler run on an open vented system?
Yes. The Purewell Variheat boiler is able to operate on an open vented heating system.
We would advise compliance with minimum pressure requirements at boiler, reference guidance note INDG436 (Health and Safety Executive).
Open vent and cold feed pipes must be installed correctly and in compliance with BS6644. You can refer to the installer guide for detailed information on Open Vent and Cold Feed pipes.
However, Hamworthy recommends the use of sealed heating systems, where possible.
If you want to know the difference between a sealed system and open vented system, find out more here.

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Can the Purewell Variheat boiler run on an open vented system?
Yes. The Purewell Variheat boiler is able to operate on an open vented heating system.
We would advise compliance with minimum pressure requirements at boiler, reference guidance note INDG436 (Health and Safety Executive).
Open vent and cold feed pipes must be installed correctly and in compliance with BS6644. You can refer to the installer guide for detailed information on Open Vent and Cold Feed pipes.
However, Hamworthy recommends the use of sealed heating systems, where possible.
If you want to know the difference between a sealed system and open vented system, find out more here.