Heat Pump FAQs
1. Who can install a heat pump system?
Any highly competent plumber should have no problems. However, unless he or she has had specific training in such installations, it can depend on whether or not the heat pump system provided comes complete with clear instructions and whether all the fittings and pipework are in place for straightforward connection to your central heating system. As there is no combustion, no special qualifications are required. Product suppliers will either install themselves or have recommended installers. Contact TV Energy for suggested suppliers.
2. Where can you install a heat pump and how easy is it to install?
Heat pumps produce some noise - similar to that of an oil fired boiler. Unlike a boiler, they also produce vibration. For this reason, heat pumps should always be installed away from occupied spaces. The best place is in a utility room, or at the back of a garage. Be aware that noise can also travel upwards, so noise from a heat pump in a utility room can travel upwards to a bedroom. Despite these caveats, noise is not a major problem for heat pumps.
3. What are the environmental and energy efficiency benefits of Heat Pumps?
Heat pumps offer a very low carbon emission method of heating any building. Unlike boilers, there is no pollution on-site. As the electricity grid gets cleaner, and more renewable electricity is brought on line, so the carbon emissions associated with heat pumps fall. There are no flammable fuels or tanks; no flue, no pilot light and no toxic exhaust gases. There are no road miles from LPG or oil tanker deliveries - serious pollution which is often not considered.
4. Can a heat pump provide hot water as well?
It is easy to assume heating loads for space heating requirements, but hot water use calculations require assumptions on usage patterns. Most suppliers will happily include an element of pre-heat, providing a proportion of the hot water requirement, but complete hot water provision would be an additional expense to factor in. It is worth bearing in mind that heat pumps dovetail well with solar hot water systems.
5. Are my ground conditions suitable for a ground source heat pump (GSHP)?
Most GSHPs use a closed-loop ground array system, such as trench based slinkies or boreholes, which use the ground as a solar heat 'battery'. This is an exhaustible source of heat energy that needs to be recharged, for example, every time it rains, and through the warmer summer months. It is essential that the design of closed-loop systems matches the heating requirements of the building and that the ground is able to recharge the heat extracted on an annual basis.
The amount of solar radiation landing at any point on the earth's surface depends on latitude and climate – not soil type. So although different soil types have different thermal conductivities, the amount of energy available from a horizontal ground array does not greatly vary with soil type. Nevertheless, great attention still needs to be paid to ground recovery capabilities; this should be covered by the installers' survey.
Bore holes will require knowledge of the local geology, which is highly variable within the UK. There will be some locations (around 10%) where it is in-appropriate. If having a bore hole based system, ensure the installer has undertaken adequate survey work to understand your ground conditions.
6. How large are heat pump units?
A typical heat pump unit for a domestic dwelling is about the same size as a large fridge/freezer. Additional space may be needed for ground connection manifolds, larger hot water tanks and, if specified, a buffer tank.
7. Can I use a heat pump to heat my swimming pool?
Yes. Swimming pools require low-temperature heat and are therefore ideally suited to this technology.
8. How much back-up heat does an air source heat pump (ASHP) require?
This will depend on the severity of each winter, but based on recent climatic experiences is not normally more than a few days a year. The additional heat source will often be direct electric heaters, or an immersion heater in a buffer tank to provide system top up.
9. How much are the running costs for a heat pump?
This will depend on the model selected and usage patterns, but unless you have an on-site renewable source of electricity, there will be costs associated with the pump. It is worth asking for running cost information when seeking a quote.