E
efficiencyman
Specs are on the site. Much the same as others. must not sp-m
Discuss Dream heat pumps. in the Plumbing Jobs | The Job-board area at PlumbersForums.net
- Status
E
efficiencyman
You can look up the dream site. The specs. are all there I do not want to be accused of something that's not true. The COP`s are much the same as other brands. 4.8 @ 11 d C -- COP of 5.2 @ 19 d C
- Messages
- 1,005
The ones that matter are the COP at 3.5°C and at -3.4°C / Output at 50°C unless you're going to tell people to upgrade all their radiators as well. - I couldn't find on the Dream website the full CoP and output charts for all the input and output temperatures - any reason why they aren't available? CoP should also take into account losses during the defrost cycle - That's the info that really matters. Also no details about whether that info would include the use of an in-line immersion. - Care to publish the full technical info please?
E
efficiencyman
Hi Worcester,
The only tech data I have seen was in the installation manual that came with the dream, so don`t know exactly the COP/Temps you ask, all I know is that it`s worked well all this last year. I have taken into account about the defrost cycle (as I posted ) No inline immersion needed (see my other post). I use it Hybrid Full Stop no need for a de-ice & use it via optomiser (auto ) when COP`s are above (say 2.4 ) At below this the ASHP is inhibited and at below a set temp the optimizer brings on my `A`rated gas boiler as it then becomes more beneficial and over comes the extra heat losses from the cold ambient air, maybe 10 - 30 days in 365 depending on the winter weather. I did also over size some of the rads. temps no problem on any of my 5 zones (6 with Koi pond). Can`t think of why tech spec is not in full, would they not be similar to Mitsubishi, Toshiba or Sanyo as mine is using their compressor ? My 15 Kw does not seem to work less efficient to me (shoves out loads of heat) but set to 48 degs. output normally, I am well happy especially saving so much gas (80%) even allowing for COP`s when used (<2.4 ) the extra leccy used has not been any thing near my previous gas bills. All in, about £500 saving per year, so hoping to recover my outlay in 4 years. P.S.1 for reasons already stated COP`s at below 3.5 or sub zero don`t matter to me as I do not wish it to freeze and make Ice, i.e. not cost saving, that's why I use it as a Hybrid. P.S.2. Similar to Hybrid vehicles when the battery is low another source is needed to charge, with heat pumps it`s only when COP`s are "frosty" we need another source in my case around 10% gas would be nice for my Hybrid ( bit more depending on climate).
The only tech data I have seen was in the installation manual that came with the dream, so don`t know exactly the COP/Temps you ask, all I know is that it`s worked well all this last year. I have taken into account about the defrost cycle (as I posted ) No inline immersion needed (see my other post). I use it Hybrid Full Stop no need for a de-ice & use it via optomiser (auto ) when COP`s are above (say 2.4 ) At below this the ASHP is inhibited and at below a set temp the optimizer brings on my `A`rated gas boiler as it then becomes more beneficial and over comes the extra heat losses from the cold ambient air, maybe 10 - 30 days in 365 depending on the winter weather. I did also over size some of the rads. temps no problem on any of my 5 zones (6 with Koi pond). Can`t think of why tech spec is not in full, would they not be similar to Mitsubishi, Toshiba or Sanyo as mine is using their compressor ? My 15 Kw does not seem to work less efficient to me (shoves out loads of heat) but set to 48 degs. output normally, I am well happy especially saving so much gas (80%) even allowing for COP`s when used (<2.4 ) the extra leccy used has not been any thing near my previous gas bills. All in, about £500 saving per year, so hoping to recover my outlay in 4 years. P.S.1 for reasons already stated COP`s at below 3.5 or sub zero don`t matter to me as I do not wish it to freeze and make Ice, i.e. not cost saving, that's why I use it as a Hybrid. P.S.2. Similar to Hybrid vehicles when the battery is low another source is needed to charge, with heat pumps it`s only when COP`s are "frosty" we need another source in my case around 10% gas would be nice for my Hybrid ( bit more depending on climate).
Last edited by a moderator:
E
efficiencyman
A genuine question was asked, so I gave a genuine reply. No advert, no intended hype, its working well. So I thought that would be OK to share, sorry if that came over upsetting to a few but I am innocent of the ad allegation, go and pay thousands more if you wish, I am satisfied and still saving.
G
Gray0689
S
stokegolding
Just looking at the Dream air pump for a new build 5 bed house but know very little about it. House is well insulated. Will have 2 log burners. Want to have rads rather than ufh as want something responsive. Live in South West so not too many days with frost. I'd appreciate it if you could tell me what else apart from the unit (they suggest a 22kw) we would need to buy. Would a plumber be able to fit it? I had a look at the fitting instructions and couldn't understand them at all. These instructions also said it was for indoors although the web site says indoors or outdoors.
B
BobsDream
I installed a 22 kw Dream heat pump in mid January this year. I bought the heat pump to use in the milder months as I already have an outdoor wood burner that can make the house a bit warm when mild outside.
I mounted the heat pump outside near the wood burner and connected up to the existing pipework and this was straight forward
I must say I’m impressed with the way it is performing in heating mode, especially since I haven’t oversized any radiators yet.
I do have a problem however. I noticed it had iced up on a couple of occasions and suspected that the defrost cycle was not working. I contacted the seller who’s customer service involves emailing the manufacturer in China and awaiting an answer. After a few days of this it was decided to try the heat pump in cooling mode. The result is that the water leaving the outlet cools quite quickly until the difference in temperature between water coming in and water going out is great enough to trigger an error code (PP06) and shuts the pump down. The manufacturer says there is not enough water flow. This makes sense, however I don’t understand why it needs more water flow in cooling mode than heating mode where it works perfectly well? My wood burner puts out probably twice the heat energy yet works flawlessly. There are two pumps, in-line, in my system so I consider the flow to be good.
So what now? I’m planning to temporarily plumb in a 200 litre tank next to the heat pump and try it in cooling mode again with the water circulating around the tank. If this cures the problem I may have to consider installing a buffer tank with large bore pipes direct to the heat pump.
I would be grateful for your thoughts on this.
I mounted the heat pump outside near the wood burner and connected up to the existing pipework and this was straight forward
I must say I’m impressed with the way it is performing in heating mode, especially since I haven’t oversized any radiators yet.
I do have a problem however. I noticed it had iced up on a couple of occasions and suspected that the defrost cycle was not working. I contacted the seller who’s customer service involves emailing the manufacturer in China and awaiting an answer. After a few days of this it was decided to try the heat pump in cooling mode. The result is that the water leaving the outlet cools quite quickly until the difference in temperature between water coming in and water going out is great enough to trigger an error code (PP06) and shuts the pump down. The manufacturer says there is not enough water flow. This makes sense, however I don’t understand why it needs more water flow in cooling mode than heating mode where it works perfectly well? My wood burner puts out probably twice the heat energy yet works flawlessly. There are two pumps, in-line, in my system so I consider the flow to be good.
So what now? I’m planning to temporarily plumb in a 200 litre tank next to the heat pump and try it in cooling mode again with the water circulating around the tank. If this cures the problem I may have to consider installing a buffer tank with large bore pipes direct to the heat pump.
I would be grateful for your thoughts on this.
E
efficiencyman
Save now as it will probably cost you when it starts needing parts
Enjoy
Actually Dream have been very helpful when I contacted them after 18 months use I had a Capacitor fail they dispatched several parts the same day (free of charge) better service than you get from most bigger companies. Especially the low purchase price of £1500 for 15 Kw to heat my whole house. I am still impressed with it`s performance and value for money, compared to all the other horrendous quotes I had in 2012.
Stokegoldng UFH would better suit HP. Rads may need oversizing. As you are well insulated, the 22 Kw may not be needed, mine is a bit oversized at 15 Kw. A plumber with calcs & knowledge should be able to install for a fixed price whether he may have the experience to get yours right first time, remains to be seen. Indoors ducting not advised, outdoors much preferred for essential air flow. Chinese instructions need re translating I agree ! but I was very impressed with a reply from China when inquired about wiring in an external digital control, they supplied details in colour within minuets.
Bobs dream "Iced over" This can/will happen with high humidity / dew point temp being met, also at these temps the COP will not be favourable, I inhibit my use with a digital optomiser, to avoid lower COP`s (light your log burner) mine swaps to gas.
PP06 error code, that's possibly frost protection not set correctly, another of my reasons for not running at those temps.
what settings are you at ? I keep heating output below 47 degs.
"2 pumps inline" are they in parallel ? Have you fitted a strainer & magna clean in line ? Good flow, Blocked, flushed ?
Regards Buffer tank, Cylinder, calcs. stats. needed.. Worcester need your expertise sir !
Last edited by a moderator:
- Messages
- 1,005
Sorry guys can't really help without knowing how it's all been plumbed in !!
Multiple heat sources, as always buffer tank, / low loss headers. Flow rate always a killer with Heat pumps - whats the minumum allowed l/min?
We ALWAYS install, in line 30µm (micron) strainers and flow gauges in heat pump systems.
Had a call out not so long ago to a 'self install' - retrofitted and not flushed, he was getting low flow rate failures every 24 nours becasue the filter was blocking up every 24 hours!! - without the filter he'd have completely b**g**d the hex (ps. is that ** allowed any more Croppie?
)
However I would have though that the Dream should have some kind of autodefrost cycle .. (usually steals heat from the buffer or heating system)
Multiple heat sources, as always buffer tank, / low loss headers. Flow rate always a killer with Heat pumps - whats the minumum allowed l/min?
We ALWAYS install, in line 30µm (micron) strainers and flow gauges in heat pump systems.
Had a call out not so long ago to a 'self install' - retrofitted and not flushed, he was getting low flow rate failures every 24 nours becasue the filter was blocking up every 24 hours!! - without the filter he'd have completely b**g**d the hex (ps. is that ** allowed any more Croppie?
) However I would have though that the Dream should have some kind of autodefrost cycle .. (usually steals heat from the buffer or heating system)
E
efficiencyman
Yes, the dream units use their own 4 way valve where the parameters can be adjusted or set as per default. The auto defrost cycle including duration time & temps are ingeniously configured to use its own "generated" heat (hot gas injection) to self defrost ice on the evaporator (does NOT steal from buffer or heating system) or as some do - NOT via an element which is not included in the COP rating.
The dream units use well proven Mitsubishi, Toshiba or (as in mine) a Sanyo compressor, the micro processor control is also a well developed design which I was easily able to relocate the remote unit inside my house next to my heating controls.
The dream units use well proven Mitsubishi, Toshiba or (as in mine) a Sanyo compressor, the micro processor control is also a well developed design which I was easily able to relocate the remote unit inside my house next to my heating controls.
B
BobsDream
Thanks for the reply E-man and all. My systen has two pumps inline, one near the heat pump and one mid system. I added the second pump when I installed the powerful outdoor wood burner and it has always worked really well, as does the heat pump in heating mode.
I flushed the system well as I wanted to add some expensive anti-freeze and I installed a strainer filter. After a few weeks running the heat pump the filter is clean.
I expect it to ice up in certain conditions and I expect the auto defrost to work too.
The auto defrost uses heat from the system, by going into cooling mode, to warm and thaw the coils but mine was not working. I was advised to manually put it into cooling mode and this is when the error code PP06 appears and the machine shuts down. PP06 = water outlet and inlet temp difference overlarge protection. You can actually see the outlet temp reduce rapidly until the code appears. The powers that be in China say the water flow is too low and the temp difference should only be around 7 degrees or so.
E-man, are you able to put yours into cooling mode manually to see what happens?
I'm waiting for some fittings and then I'm going to rig up a test buffer tank with unrestricted flow to see if the cooling mode works. If it does I would consider installing a buffer tank next to the heat pump with big bore (28mm) pipes.
Nostrum, one year warranty!
Cheers
bob
I flushed the system well as I wanted to add some expensive anti-freeze and I installed a strainer filter. After a few weeks running the heat pump the filter is clean.
I expect it to ice up in certain conditions and I expect the auto defrost to work too.
The auto defrost uses heat from the system, by going into cooling mode, to warm and thaw the coils but mine was not working. I was advised to manually put it into cooling mode and this is when the error code PP06 appears and the machine shuts down. PP06 = water outlet and inlet temp difference overlarge protection. You can actually see the outlet temp reduce rapidly until the code appears. The powers that be in China say the water flow is too low and the temp difference should only be around 7 degrees or so.
E-man, are you able to put yours into cooling mode manually to see what happens?
I'm waiting for some fittings and then I'm going to rig up a test buffer tank with unrestricted flow to see if the cooling mode works. If it does I would consider installing a buffer tank next to the heat pump with big bore (28mm) pipes.
Nostrum, one year warranty!
Cheers
bob
E
efficiencyman
I fitted my own weather optomiser control wire directly into the provided link on main HP PCB.
You won`t find an inverter driven compressor at a dream price of £1500 for a 15 Kw unit.
High spec & manual on their web site. Don`t want to be accused of spam, easy to find.
Normal 12 months warranty but I have been impressed with Dreams after sales service and they sent parts by same day carrier free of charge after my 12 months that speaks of good reputation to me. Better than I have had from big named brands.
You won`t find an inverter driven compressor at a dream price of £1500 for a 15 Kw unit.
High spec & manual on their web site. Don`t want to be accused of spam, easy to find.
Normal 12 months warranty but I have been impressed with Dreams after sales service and they sent parts by same day carrier free of charge after my 12 months that speaks of good reputation to me. Better than I have had from big named brands.
- Status
Reply to Dream heat pumps. in the Plumbing Jobs | The Job-board area at PlumbersForums.net
Similar plumbing topics
Newest Plumbing Threads
-
-
-
-
-
SAdvice on moving toilet from front of house to the back.
- Started by Steve F
- Replies: 0
-
-