Monobloc/Through The Wall Combined Indoor Air Conditioning Unit and Heat Pumps

What is a monobloc/through the wall combined indoor air conditioning unit and heat pump?

Monobloc air conditioning units have both the condenser and evaporator combined in the indoor air conditioning unit so there is no outdoor unit. This can be an advantage where space outside is of a premium or external aesthetics is an issue such as listed buildings, hotel bedrooms, conservatories and the like.

Are monobloc/through the wall air conditioning units available with heat pumps built in?

Yes, monobloc air conditioning units can be purchased with a heat pump so the unit can deliver both cooling and heating as required. The units can also be purchased with inverter controls to deliver optimum efficiencies. Where monobloc units form the sole source of heating, a unit is available with an on board electric heating element which allows the unit to operate as a stand alone electric fan convector for those unusually cold days and nights.

Cooling only units are also available for use in conservatories and inherently warm locations which can become uncomfortable to occupy otherwise.

What is involved in installing a monobloc/through the wall air conditioning unit?

Monobloc air conditioning units and heat pumps can be installed easily and quickly with the minimal amount of mess and disruption by a competent installer.

Two ducts require drilling through the wall for intake and extract air. An electrical supply is required adjacent the unit and a route for a condensate hose to be evacuated is also required.

Can I install my own monobloc/through wall air conditioner?

Whilst these units can be installed very quickly with minimal disruption, it is recommended that a competent trained engineer installs the units in order for the warranties to be maintained.

What size air conditioning unit would I need for my conservatory?

Conservatories are inherently warm locations due to their high solar gain and quite often south facing aspect. In order to make a conservatory habitable quite often cooling is required. In order to keep cooling costs to a minimum we would recommend a few simple steps are taken:

  • 1/ install heat reflective glass or films to windows
  • 2/ install Venetian blinds to block the suns rays
  • 3/ install air conditioning to remove the remaining heat

In order to calculate the exact cooling/heating requirement for your conservatory the dimensions, orientation and construction is required. However, as a rule of thumb the cooling capacity required to reduce the room to a comfortable temperature can be calculated by multiplying the square area of the conservatory by between 250W and 400W depending on the above criteria.

In a small conservatory one single unit would probably be enough to give adequate cooling to reduce the heat to an acceptable level. In larger conservatories multiple units may be required. If multiple units are required then it may be worth considering installing a split system, (see advantages/disadvantages below).

What are the servicing requirements of a Monobloc/Through Wall Air Conditioner?

Periodical cleaning of the air filters is require and can be carried out by the owner/user.

Cleaning of the condensing battery and the condensate management system is also required periodically.

The intervals between cleaning will depend on the environment the unit is operated in and the frequency/duration of use.

Advantages/disadvantages of a monobloc/through the wall air conditioning units compared to split air conditioning systems

Monobloc v’s split system

No outdoor unit is required on a monobloc system making the unit discrete from the outside

Monobloc units generally have larger indoor units than split system due to both the condenser and evaporator being housed in the same unit making them a bit bulky in comparison

Monobloc units are simple, easy and quick to install with no specialist tools and equipment required

Monobloc units have limited capacity due to their compact size

Monobloc units typically run COP’s (Coefficient Of Power) of 2.6 to 3 where their split counterparts are more efficient with typical COP’s of 3.6 plus. (see below for explanation of COP).

With a COP of 2.6 to 3 a monobloc returns excellent efficiency when compared to resistive electrical heaters and some oil fired systems.

Split systems are more versatile and can be recessed into ceilings with the indoor units being located away from the controlled environment using insulated ducts to deliver the cooling/heating.

COP (Coefficient Of Power) explained – The COP of a unit is how much input energy is used compared to how much output energy is given. For example, a system with a COP of 3 will use 1 kW of electrical energy to drive the unit whilst giving out 3kW of heat energy. The gain in performance is achieved by extracting heat from the atmosphere. However the cooler the atmosphere, (generally below 5 degrees Celsius for most heat pumps), the lower the COP drops as the heat in the atmosphere becomes more intensive to extract. A resistive electric heating element will operate at a COP of 1 making the heat pump much more efficient to run, even in very cold conditions below zero. Most heat pumps will not reach COP’s of 1, (unity) until outside temperatures go below -10 degrees Celcius.

If you require further information, a quotation for an installation or just simply to talk through options, then please give us a call on 01509 341971 or drop us a line at: