Mitsubishi PEAD Ducted Heat Pumps

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mrfee

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#272078 8-Jun-2020 18:46

We are in the process of getting quotes for a ducted heat pump system for the four bedrooms of our house. We have a high wall in the open plan lounge/dining/kitchen which we are happy with so are only looking at ducted for the bedrooms, this means we can use a smaller unit and don't have to worry about zoning.

A number of installers in Auckland have come through and quoted various systems (Fujitsu, Panasonic, Mitsubishi in increasing order of cost). I have a slight preference for a Mitsubishi system based on positive word of mouth experience, their brand reputation and the fact that from what I hear their WiFi interface can be made to work well with Home Assistant to add a bit of automation. I also have an existing fresh air duct that I would like to integrate to periodically introduce fresh air into the system which is also supported as well as the option to add on the Lossnay balanced ventilation system in the future.

One installer has mentioned that the Mitsubishi PEAD-XX systems don't have an automatic fan speed setting. The fan speed has to be set to either low, med, high manually. I thought this was a bit odd given the high wall units I have ever seen from any manufacturer have an auto fan speed setting and the ducted systems from the other manufacturers also have this mode. I called up Mitsubishi Electric NZ who confirmed that this model series supports manual fan speed only.

I know a few people here do have this system so I was wondering if this has ever proven to be an issue or a point of annoyance? Given the outlets will be in bedrooms and generally running overnight when people are in the rooms, I would imagine we would want the fan speed set to low anyway to minimise drafts etc.

Thanks for the help!

RunningMan

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#2500781 8-Jun-2020 19:03

Check what happens to the fan speed at each of those settings on both heat and cool settings. This info probably won't be in any sales brochure. For example, have a Panasonic ducted system that on heat, the fan speed drops to zero (when set to low/med/high) when not actually heating to avoid drafts. It runs for a few seconds every few minutes to ensure there is enough air circulation to measure the temp and only runs the fan continuously when heating. On cool mode (low/med/high speed), fan doesn't stop at all, unless you set the speed to auto, in which case it can ramp up to full speed when cooling, and drops to zero when not.

Think about vent placement to avoid being in any draft. Also need to consider if you want the bedroom doors open or closed. If the doors are open, then you can have a single return vent in the hallway, but if you want the doors closed, then you need a return vent in each room. Which ever way you design the system is how it will work best. Also make sure they have dampers for each supply vent to adjust the flow balance to each room, don't just rely on the adjustment at the vent itself as it probably won't give you enough variation to balance different size rooms at the end of different length and shape ducts.

E3xtc

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#2501147 9-Jun-2020 08:30

Yeah what RunningMan has said. The way we use ours is usually either on Medium/High for cooling in summer to take the heat out of rooms before trying to sleep, or during winter when it is set to low to maintain a minimum level of warmth in the rooms (so as RunningMan mentioned - ours is also Panasonic - it just quietly runs a small amount of air through, and then if it needs to, just pushes some warm air into the rooms to maintain that minimum).

I would have liked some more ability to integrate ours with wifi/etc (which it can even though its an older model now) but tbh I just can't be bothered as its usually set and forget anyhow.

mrfee

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#2501737 9-Jun-2020 20:55

E3xtc:

Yeah what RunningMan has said. The way we use ours is usually either on Medium/High for cooling in summer to take the heat out of rooms before trying to sleep, or during winter when it is set to low to maintain a minimum level of warmth in the rooms (so as RunningMan mentioned - ours is also Panasonic - it just quietly runs a small amount of air through, and then if it needs to, just pushes some warm air into the rooms to maintain that minimum).

I would have liked some more ability to integrate ours with wifi/etc (which it can even though its an older model now) but tbh I just can't be bothered as its usually set and forget anyhow.

Thanks for the replies. Out of interest, what made you decide to go with the Panasonic system? I am struggling to decide on which system to go for - there is really not much between all the main manufacturers. I have heard that given they are all so similar, it is the quality of the installation that makes the biggest difference so go with a reputable company with a lot of experience in installing ducted systems specifically which sounds like good advice.

tanivula

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#2501740 9-Jun-2020 21:25

Interestingly I had a PEAD system in our old house and now have a Panasonic one in the new. Yep, the Mitsi just keeps running and doesn't change speeds. The outdoor unit ramps up and down (and off) but the indoor system keeps the flow of air. I did find it annoying as once the outdoor unit has stopped, non heated / slightly cool feeling air would circulate until it hit the required temp to turn the outdoor unit on again.

I partly went with Panasonic this time for the price / that annoyance. Both outdoor and indoor units fluctuate, when on heating mode and the detected temp hasn't activated heating, the indoor fans would turn on for a brief period to push air around so that the temp sensor can get a 'new' reading.

I guess the main issue would be if the vents are going to be close to your beds and you get the blowing of air on you.

Pro's for the Mitsi

true integration with the losnay
wifi control (the Panasonic one is bollocks and is being replaced by something else last I checked)

Pro's for the Panasonic

should be slightly cheaper
less cold air being blown at you

mrfee

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#2502255 10-Jun-2020 14:42

tanivula:

Interestingly I had a PEAD system in our old house and now have a Panasonic one in the new. Yep, the Mitsi just keeps running and doesn't change speeds. The outdoor unit ramps up and down (and off) but the indoor system keeps the flow of air. I did find it annoying as once the outdoor unit has stopped, non heated / slightly cool feeling air would circulate until it hit the required temp to turn the outdoor unit on again.

I partly went with Panasonic this time for the price / that annoyance. Both outdoor and indoor units fluctuate, when on heating mode and the detected temp hasn't activated heating, the indoor fans would turn on for a brief period to push air around so that the temp sensor can get a 'new' reading.

I guess the main issue would be if the vents are going to be close to your beds and you get the blowing of air on you.

Pro's for the Mitsi

true integration with the losnay
wifi control (the Panasonic one is bollocks and is being replaced by something else last I checked)
Pro's for the Panasonic

should be slightly cheaper
less cold air being blown at you

Awesome, it's great to hear from someone that has experienced both!

It is particularly telling that you chose to go with Panasonic after having experiece with the Mitsi. Reading your summary does tilt my thinking more towards the Panasonic. It's hard because as someone mentioned earlier it is the stuff that isn't in the sales brochures that actually matters the most. Things like what the system does when it is at temp or whether it blows cold air on startup etc.

Regarding the Panasonic WiFi - one installer showed me the Panasonic ducted system on his phone and it looked pretty good to be honest, showed live power usage and a bunch of other interesting stuff. Perhaps they have released the replacement to the bollocks WiFi by now? Not sure on the home automation integration but it may just end up being set and forget anyway.