Vaillant thermal insulation for PHE C 360-70 plate heat exchanger

Vaillant thermal insulation for the PHE C 360-70 plate heat exchanger

This thermal insulation is an original Vaillant accessory intended exclusively for the PHE C 360-70 plate heat exchanger (exchanger order number 0020137071). The insulating cover is shaped precisely to the dimensions of the exchanger body (421 × 532 × 636 mm, connection height K 246 mm) including cutouts for the side connections of both the primary and secondary circuits, and fulfils three key functions: safety (prevents accidental contact of the operator with the hot surface of the exchanger), energy-saving (reduces heat losses by radiation and convection into the surrounding plant room) and anti-condensation (limits condensate formation on the surface of the exchanger during operation with lower secondary medium temperatures, e.g. when connected to a heat pump circuit).

According to the official Vaillant installation manual for the PHE S/PHE C series, there is an explicit safety warning: „Wärmetauscher kann im Betrieb sehr heiß werden – Verbrennungsgefahr“ (the exchanger may become very hot during operation – risk of burns). This insulation is precisely the recommended solution for eliminating this risk in real boiler room operation without the need for additional protective measures or restricted access to the area.

Parameters of the protected PHE C 360-70 exchanger

Overview of the entire Vaillant PHE series (official manufacturer technical data)

Plate material: stainless steel. Operating temperature (material range of the plates): -196 °C to +200 °C. The PHE S model has a threaded connection 1 1/4", the PHE C models have flanged connections. Source: Vaillant installation manual „Externer Plattenwärmetauscher PHE S, PHE C“, document 0020196730_00.

Construction of the insulating cover

The cover is made of closed-cell thermal insulation foam with a black surface, resistant to the typical temperatures found in boiler room operation. The construction is designed as a demountable, shape-adapted enclosure that follows the angular body of the PHE C 360-70 exchanger and leaves free access to the side connections of both the primary and secondary circuits, as well as to the venting and drain fittings, if included in the assembly. Thanks to its sectional construction, the cover can also be fitted subsequently onto an already installed and connected exchanger, without the need to dismantle the piping.

Installation of the insulating cover

1. Before fitting the insulation, it is recommended to complete the installation and pressure-test all exchanger connections.
2. The cover is fitted onto the exchanger body in its individual parts so that the cutouts precisely align with the side connections of the primary and secondary circuits.
3. The cover parts are joined together (depending on the design – clips, hook-and-loop fastener, or an overlap with a retaining clip) so that no gaps are formed through which heat could escape or contact with the hot surface underneath could occur.
4. Before putting the system into operation, it is recommended to visually check that the cover does not obstruct the space needed for operating shut-off valves, venting, or any future measurement interventions.

Servicing, cleaning and care

If signs of limescale or dirt build-up appear (typical with hard or contaminated water), the exchanger is cleaned as follows: the system is taken out of operation, the exchanger is drained and removed. Only cleaning agents suitable for stainless steel and copper should be used – unsuitable cleaning agents can permanently damage the exchanger. Flushing with the cleaning solution is carried out against the normal flow direction, after which the exchanger is flushed with clean water, reinstalled, and it is recommended to check the water hardness before restarting. In case of high water hardness, treatment of the heating water is recommended in line with the documentation of the other system components – atria.sk offers, in the category chemical and physical water treatment, corrosion inhibitors and cleaning agents from the SENTINEL and ULTIMA ranges for this purpose, which extend the service life of both the exchanger and the entire boiler room.

In case of temporary shutdown (repair, servicing, longer outage), it is recommended to fully drain and clean the exchanger to prevent damage from freezing, aggressive media, or biological fouling. When permanently taking the exchanger out of operation, the primary circuit is closed first, then the secondary circuit, followed by draining and disassembly.

Compatibility and related accessories

The PHE C 360-70 exchanger belongs to the PHE C series, which is always installed together with the supplied floor bracket with height-adjustable feet. When completing the assembly, we recommend adding the following original accessories from the same category on atria.sk:

• DN65 connecting pipe (code 0020107886) – a flanged connecting part for PHE C models up to 360 kW, into which, besides the main flow/return, additional fittings can also be connected (venting, draining, thermometer, pressure gauge).
• Connecting pipe insulation (code 0020248930) – a thermal cover for the aforementioned connecting part, for complete insulation of the entire assembly, including the pipe connections, not just the exchanger body itself.

Typical application scenario

Schools, wellness centres or swimming pool facilities with high and relatively constant heat demand for water heating and space heating are typical buildings where a cascade with an output close to 360 kW is installed. In such facilities, staff without specialised technical training (e.g. a lifeguard, caretaker) often move around the plant room, which is why thorough covering of the hot surfaces of the exchanger is an important element of operational safety, not only of energy savings.

Why an improvised solution is not a good choice

In practice, we sometimes encounter a makeshift solution where the installation company simply wraps the hot exchanger in mineral wool and secures it with tape or wire. This kind of solution is problematic for several reasons: mineral wool absorbs moisture from the surroundings and loses its insulating properties, it does not precisely follow the shape of the exchanger (creating gaps with heat loss and risk of contact), and during servicing it usually has to be completely discarded and replaced with new material. The original, shape-adapted Vaillant cover, on the other hand, retains its shape and insulating properties over the long term, can be repeatedly removed and refitted without loss of function, and its appearance matches the professional level of the rest of the boiler room equipment.

Energy and operational benefits of the insulation

An uninsulated metal surface of a large-area plate heat exchanger represents a constant source of heat loss by radiation and convection into the surrounding plant room space during operation. In models with higher output (and therefore also a larger body surface area, as is the case with the PHE C 360-70 model), this effect is more pronounced than in small domestic appliances. Covering the body with suitable thermal insulation is one of the simple and low-cost measures that can noticeably reduce these losses without interfering with the functional part of the system – similarly to how distribution pipes and fittings in the same boiler room are commonly insulated. Together with the other accessories (e.g. connecting pipe insulation), this creates a comprehensively insulated assembly that reduces the overall heat losses of the plant room and contributes to a more stable and predictable operating temperature in the given space.

Why choose original Vaillant insulation for the PHE C 360-70

• Precise shape match with the PHE C 360-70 exchanger – no additional adjustments or trimming required, unlike universal insulations available on the general market.
• Increased operational safety in line with the manufacturer's explicit recommendation in the installation manual.
• Reduced heat losses and thus also a slight improvement in the real efficiency of boiler room operation.
• Demountable construction does not hinder routine servicing or occasional inspection of the exchanger.
• Long-term stability of shape and function compared to improvised solutions made of mineral wool or other materials.
• The PHE C 360-70 model is used in medium-sized buildings – schools, larger residential complexes, wellness centres and swimming pools – with an installed boiler room output of up to 360 kW.

When ordering, we always recommend verifying that the exchanger order number 0020137071 matches the model stated on this page (PHE C 360-70), as the individual covers of the PHE C series are not interchangeable with each other and differ not only in outer dimensions but also in the precise placement of the cutouts for side connections and any floor bracket. If you have any doubts when choosing the correct part, we recommend contacting atria.sk customer support or the designer of the given heating system directly.

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