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Swipe

Can a single indoor unit be ducted or would I have to go for the Mutsubishi Electric split unit system instead?

richardc1983

Swipe wrote: »

The hallway is where the orange block is mounted. Bedroom1 is the room between the orange and red blocks. I'm thinking it might be better placed either above the front door or above the kitchen door. My log burner is in the lounge.

Your engineer is correct if the unit is mounted on that wall where the orange block is the hot air is going to bounce off the short distance of the wall opposite and then its going to short cycle back into the unit and make the unit think its reached temperature. You need to have a gap in front of the unit for instance it would be better mounted above the kitchen door in the hallway so it is blowing down the length of the hallway.

The problems your going to come into though is that the air temperature sensor is inside the unit, the hallway is going to heat upto temperature a lot quicker than the other rooms as the heat will build up.

This will make the hallway unit think its reached temperature and either ramp right down reducing output or shut off completly until the temp in the hallway has dropped.

I would be carefull if you are to assume the other rooms will be heated upto a suitable temperature. YOu may find that your hallway becomes unconfortably hot as you compensate by turning the temperature right up on the unit so as to get some heat into the other rooms.

Your house is a bungalow, you would be best off spending the extra and having a ducted system. As the space above your house is a loft space this would be perfect as you could have the return air back to the ducted unit in the loft.

It seems you are trying to find a cheap heating solution and expecting it to heat the ground floor.

You are going to be dissapointed I feel.

It is worth spending the extra on a ducted system.

Its not that unit is not capable of outputting the heat but it will struggle to get the heat round corners and into the rooms, air throw from these units is about 4 meters. These units are supposed to heat one room only and designed for that, situations such as steveheads below work due to where the unit is mounted. He has though 2 units installed.

Stevehead mounted a unit on his landling, the units blow directly into the bedrooms across from the unit by about 1mtr distance. There is also heat rising up the stairs from downstairs also helping to heat the upstairs area.

Take advice from the experts. either go for a unit in the hallway above the kitchen door and also have a unit mounted in your main bedroom. The heat will gradually find its way out of the bedroom and out into the hallway.

Multi split systems are available where you can connect more than one indoor unit to one outdoor unit.

Carefully consider the above before you agree to do anything, if your installer is telling you it wont work then he is correct, I can see you will run into trouble straight away from diagram alone.

If you wish to discuss this on the phone, please PM me your number and ill be happy to chat in more detail about it.

Regards
Richard.

richardc1983

Swipe wrote: »

Can a single indoor unit be ducted or would I have to go for the Mutsubishi Electric split unit system instead?

I am assuming you are hoping to have a unit like this installed in your hallway as per diagram:

http://www.ajmadison.com/ajmadison/images/large/09KHS71_Evap_Cond.jpg

This is where I have stated it wont suit your layout:

You require a system like this

http://www.airconditioningwarehouse.com.au/images/ducted_house.jpg

This is how the layout would be

The indoor unit looks like the silver units in the below link:

http://www.airconworld.co.uk/images/products/Ducted%20CDT%2012-48%20AM%20Range-Final-1.jpg

These units are conceiled in the loft space out of the way, you would have square grilles in the ceiling of each room you intend to heat/cool and a return air grille in the hallway leading air back to the unit to heat/cool the air. This means that because the grille in the hallway is sucking air it pulls air through the halllway meaning your hallway would get warm/cool depending on if summer or winter due to the airflow.

They are still classed as a split system, as you say Mitsi Electric do them but all manufacturers also do their own version of them. THey operate the same though.

IF you can afford Mitsi Electric, do go for it, you are buying the best!

If you cant afford a ducted split system, then go for two splits either off of a multi outdoor unit or two separate outdoor units.

One unit mounted in the hallway above kitchen door and blowing down and also a unit in your main bedroom so as heat is at both ends of the house and it will mix through gradually if doors left open.


REgards
Richard

Swipe

Thanks very much for that Richard and I take on board what you say about air travelling around corners into other rooms etc. I'm having a quote for a water based radiator system (recommended by the supplier who advised against air units) so I'll see how much that comes in at. I'm doubting it will be cheap as I will needed new radiators as mine are very old, single fin and some have leaky valves.

The ducted system looks great so it will be interesting to see how much it comes in at compared to the water based system or two separate pumps (one above kitchen door and one in the bedroom, as suggested by yourself).

Does anyone recommend airconworld based in Gloucester? I'm assuming they would cover my area.

Andy_WSM

Hi Swipe.

I have both a ducted air system and a water based ASHP.

Reason: I had the ducted A/C put in as I run servers at home and needed the cooling in the Summer. I never intended it to be used as a heating system. However; last Winter it got me out of a spot when my boiler broke down and worked very well for heating the whole house - cheaply too. However; I personally wasn't keen on the drafty heat. So I had the boiler repaired.

This winter it went wrong again (majorly) so I decided to shell out for a wet ASHP - and consider it to be the best purchase I have made in a while. I had to fit a hot water tank too, but given the unreliability of my boiler in recent months, it is an absolute luxury to know I can turn the tap and water is going to come out of it - and hot too!

My running costs are dropping by the day as we move into warmer weather. The unit is still set so that it is able to come on and provide heat when and where needed (thermostatic valves). All my heating & hot water (both available 24 hours a day) is currently costing just under £1.50 per day.

Swipe

Thanks Andy, I've just requested a quote for a ducted system so it will be interesting to compare the two. I'll make a decision based on the results. I suppose with the water system it would also do my DHW so I could do some calculations and see it it made sense to come off off E7.

richardc1983

Make sure they quote you for Mitsi Electric as they are the best systems money can buy!

Oh and swipe... you can thank us by pressing the thanks tab at the end of our post!

Swipe

Do any of your heap pump manufacturers say that the 3 year warranty is only valid if you take out their maintenance service contract or does the 3 year warranty stand as is?

Andy_WSM

Swipe wrote: »

Do any of your heap pump manufacturers say that the 3 year warranty is only valid if you take out their maintenance service contract or does the 3 year warranty stand as is?

I just checked my warranty (which is 2 years). It is valid as long as the unit is installed in accordance with the manufacturer guidelines and by a HVAC engineer (which it was). No recommendations for servicing, other than keep the coils clear of dust & debris.

richardc1983

Swipe wrote: »

Do any of your heap pump manufacturers say that the 3 year warranty is only valid if you take out their maintenance service contract or does the 3 year warranty stand as is?

Mitsi Elec offer a standard 3 yr parts warranty, and if your installer is an accredited mitsi electric installer you get a 5yr parts warranty which is really good.

Most installers will give a year labour warranty also.