This partly pumped-up pre–Bank Holiday prattle promenades precariously across the perpetually prickly path of `inflatable` heat pumps.
As we all tumble through ASHP selection we tend to focus on the worst-case ambient/air on temperature. Minus 4oC oft the chilly datum.
But the Gods (or God, or reincarnated budgies – we must be so careful these days) they do cast us about like playthings.
For the duty available at the heat pump depends on the temperature that Carol @ BBC Weather (other weather reporters available) advises us for that day.
The dry bulb temperature (oC) on to the heat pump varies significantly through a winter`s or spring morn. This directly relates to the duty available (& efficiency) of the ASHP.
It could be said therefore the duty of the heat pump is `inflatable`. (See below)
When duties are requested (worse case) selections are made.
- At -4oC outside air, one of our bestselling ASHP does 78.5kW (@65oC Water) – if we have balanced primary & secondary side correctly (78.5kW/78.5kW) then `wahoo – life is good`.
- At ZerooC that same heat pump (again @65oC Water) inflates to 86.9kW – is there now an imbalance on the primary secondary side (86.9kW/78.5kW) ? If so the ASHP will cycle, which is fine. Mass is needed though as `Mass is Good`
- When clouds part and the `sun does crack the heavens` that same wonder-box at +8oC inflates to 104kW. (104kW/78.5kW) – which is also fine – `Mass is Good`
The big question as we apply inflating ASHPs is ………where do you `pitch` your duty ? This temperature variation could happen in one day in Gateshead.
