Air to Air Vs Air to Water Heatpumps. Now closing the gap.

[Dec27]

The only reason why a gas boiler is cheaper to heat your home at the moment is from elictricity prices being 4 times higher. By utilising a solar battery system those costs go way down. If electricity prices were down everyone would jump on heatpumps. The way to get even better value and lower upfront costs is to fit air conditioning heat pumps and you get the benefits of heating and cooling as well as air purification. Utilise your existing combi purely for hot water . Win Win.

As long as it can produce enough kWh mate.

That’s my main objection with heat pumps.

And like I said, training is free and they are pushing it hard at the min.

Ivor thinks *********************************

 

[MNW67]

As long as it can produce enough kWh mate.

That’s my main objection with heat pumps.

And like I said, training is free and they are pushing it hard at the min.

Ivor thinks wheels are held on with friction and wheel nuts serve no purpose….

This is probably a bit of a diversion. But the issue today isn't whether heat pumps can produce enough kWs on freezing days. It's how well they control that power when it's mild outside. Poor low-load control ruins the system's efficiency.

 

[Dec27]

This is probably a bit of a diversion. But the issue today isn't whether heat pumps can produce enough kWs on freezing days. It's how well they control that power when it's mild outside. Poor low-load control ruins the system's efficiency.

Heat pumps main down fall is when poorly spec’d and the temp drops below the point they become useless.

Heat pumps are best suited to a low load, so today they would be happy doing next to fek all. Much like central heating l

 

[Highway Man]

As long as it can produce enough kWh mate.

That’s my main objection with heat pumps.

And like I said, training is free and they are pushing it hard at the min.

Ivor thinks wheels are held on with friction and wheel nuts serve no purpose….

Well you will know better about heating system design than most of us, my own experience of wet system heat pumps wasnt a great experience, but the air to air heatpumps (air conditioning) we have fitted works an absolute treat for us where the wet system heat pump failed.

 

[Highway Man]

The way I see it is that if you have a house with heat loss through poor insulation then you need to be putting more in as otherwise you will be losing it, a gas system can cope better in this scenario as it can produce more heat and can run the radiators hotter, a heat pump is low temp and needs to be running virtually 24/7 because of the rads are not as hot as a traditional gas heating system

 

[MNW67]

Heat pumps main down fall is when poorly spec’d and the temp drops below the point they become useless.

Heat pumps are best suited to a low load, so today they would be happy doing next to fek all. Much like central heating l

So, to take your mini mansion with I think you said has 18kW heat loss at -3C. That would be 23.25kW heat loss at -10C. You need a 30kW rated (@+7C) ASHP to produce 23.25kW at -10C. Then in mild weather you might only need 7 or 8 kW. So the efficiency and short cycling would be terrible.

 

[Highway Man]

So, to take your mini mansion with I think you said has 18kW heat loss at -3C. That would be 23.25kW heat loss at -10C. You need a 30kW rated (@+7C) ASHP to produce 23.25kW at -10C. Then in mild weather you might only need 7 or 8 kW. So the efficiency and short cycling would be terrible.

It doesnt quite work out like that if the system has been designed correctly, in these examples you would compensate for this by a weather compensation temp control where the water temp is lowered to avoid this and also a buffer tank can be fitted to also prevent this, our old system had neither and suffered through poor design, the cost of upgrading it wasn't worth it as it was cheaper to take it out and replace it with a trad gas boiler.

 

[Dec27]

So, to take your mini mansion with I think you said has 18kW heat loss at -3C. That would be 23.25kW heat loss at -10C. You need a 30kW rated (@+7C) ASHP to produce 23.25kW at -10C. Then in mild weather you might only need 7 or 8 kW. So the efficiency and short cycling would be terrible.

I’m fairly ****4d mate, on my hols for the F1.

But a heat pump wouldn’t touch the sides.

Where did you get the calc’s from

It doesnt quite work out like that if the system has been designed correctly, in these examples you would compensate for this by a weather compensation temp control where the water temp is lowered to avoid this and also a buffer tank can be fitted to also prevent this, our old system had neither and suffered through poor design, the cost of upgrading it wasn't worth it as it was cheaper to take it out and replace it with a trad gas boiler.

Buffer tank for heating ?

WC slows the flow temp and circulation via OT

 

[Highway Man]

I’m fairly ****4d mate, on my hols for the F1.

But a heat pump wouldn’t touch the sides.

Where did you get the calc’s from



Buffer tank for heating ?

WC slows the flow temp and circulation via OT

We got reccomeded to have a buffer tank installed, it was to help lower the temp of the return water which in turn helps with short cycling

 

[pete01]

Whats wrong with a combi boiler?

Asking for a friend...

 

[Highway Man]

Whats wrong with a combi boiler?

Asking for a friend...

It isnt renewable

 

[MNW67]

I’m fairly ****4d mate, on my hols for the F1.

But a heat pump wouldn’t touch the sides.

Where did you get the calc’s from

A heat pump could provide the heat at -10C. It's just that it would be massive and therefore very inefficient and short cycling all the time in more normal temperatures.

 

[pete01]

It isnt renewable

So what?

 

[Highway Man]

A heat pump could provide the heat at -10C. It's just that it would be massive and therefore very inefficient and short cycling all the time in more normal temperatures.

weather compensation controls can lower the temp. This is the problem with air to water heat pumps on retro fits. They really are not designed for this purpose, the new build houses are better suited and the whole system needs to be designed for these more than trying to retro fit them into older properties. They need a lot of design and calculations for a retro fit.

 

[Highway Man]

So what?

efficiency and running costs