Is the air con too small

[Abe]

Need advice on a Daikin unit. Installed in a larder room which contains a 45 cubic foot chest type freezer and a hot water geyser. Room gets quite warm therefore. Room is completely enclosed with no fresh air , almost like a cold room. The only cooling is from a 9000 btu air conditionining unit.
Back pressure is reading 50 Psi running on R22. Temp within room is around 25C
Room measures 12 feet X 10 8 feet wide. 10 feet high Compressor on freezer unit is 3/4 Hp.
Air Con is working its heart out. Is the air con sized right? Would a air exhaust fan to expel the heat generated from the chest freezer help? Or a bigger sized air conditioning unit
All components on air conditioner check out right

[Brian_UK]

Originally posted by Abe
snip- and a hot water geyser. Room is completely enclosed with no fresh air ...
Would a air exhaust -snip

Abe, is this 'geyser gas powered? if it is then were is the combustion air coming from and why are you working in such a dangerous place?

Yes, any ventilation will normally help dissipate heat.

It does appear that the A/C is undersized if it will not achieve a lower temperature but holding 25°C isn't too bad for the equipment listed.

Mind you I expect if you set the temp. control at 25 the temperature would start sitting around 26

[Abe]

Thanks Brian,
The geyser is electric powered, 230 volts. Location is South Africa where they dont have gas, geyser is a big beast 200 gallons capacity.
Ive put to the customer that air con is undersized.

[Gary]

Did the room, in the past, maintain the desired temperature? If so, what has been added since then?

What is the desired room temp?

What is the kW usage for the geyser?

If you install an exhaust fan, the room will be in a negative pressure. You should bring in fresh air to make up for the exhausted air. That fresh air will add some load, however. It would be better, cooling-wise, to duct the fresh air and exhaust directly to and from the freezer condenser.

[subzero*psia]

What is the wattage the freezer condensing unit runs at? What is the load on the freezer, what product is it and what is the temperature of the product when it goes into the freezer, also how many pounds of of product and how often is it loaded?

Geyser... I am afraid you have me there, I don't know what it is by that term?

If the freezer is a 200 volt unit and runs at 7 amperes then your condenser alone is putting out roughly 4500 btu/hr. And that doesn't account for the btu's being removed from the product either... nor does it account for people that may be in the room nor lighting. And on top of that you have this "geyser" unit? I realize this post is coming in late, but can you give us any more information and if you did upsize the system (sounds like a good idea), what size system did you go to?

[WebRam]

not often that you get caught out Dean

a "Geyser" is a hot water boiler

[subzero*psia]

WOW!! In that case I can see what could possibly be a huge problem for a 9000 btu/hr air conditioner! Odd that the boiler is in an a/c room rather than a room all to itself with a fresh air supply... hmmmmm.

[Jack Lester]

I don't know much about Air conditioning but it would seem to me that your very undersized. A 3/4 hp compressor develops a lot of heat. Heat of compresson, work heat from the motor and heat of rejection. I don't know what a hot water geyser is but it sounds like it generates heat also. Are the walls insullated? If so with what? Is it a high use area? 25c is very warm. I would say you need to atleast double the size.If it were me I'd go to 24k BTU.. Who knows what else they might want to stick in there. Good Luck Yikes I just read down looks like all the bases have been covered.. I now know what a water geyser is...LOL

[Abe]

Sorry for my delay in responding to all the help Im getting. Im in South Africa at the moment , the owner of the site in question is the owner of the JUMBO CASH AND CARRY in Fordsburg, and a rich guy, whos gone into the trouble of installing an air con in his larder!!!
His got a mansion in Jan Smuts Ave near Wits,

Actually an air con company sold him the air con, saying it would solve his problems.
I would have gone for a cellar cooling type system instead, Theres a large chest type freezer and this huge boiler in the room, and its like a sauna in there, with no air in, or air exhaust in place.
Ive told him that the 9000 btu system is too small.

Thanks for the help Brian trying to organise a local tech to help, my cell no is 083-725-1548

By the way I met Andre at Coolfrost in Boksburg. He says Hello to you.

Im returning to UK shortly, the violance here is scaring me silly, the fear is even worse!!! of being hijacked and mugged !!!

[subzero*psia]

Sheesh! Sounds like you guys need a war dog for a side kick to watch your back!

[Abe]

Hello Brian,
I gave you the wrong cell number, its 083-725-1543
Im flying out tomorrow evening, Thursday, to Birm and on to Leicester
My number in UK is 0116-2627540
Ill return to SA end of June
Ill read up your report properly when I get home
Im actually in Vereeniging tonight, near the River Square Shopping Complex
Ill try and see Andre tomorrow before I leave
He says he knows you well
Talking about hijacking, Two guys try to rob me in Pretoria yesterday.

[nick_nst@aapt.n]

Hi Aiyub
Looking at the back pressure you've measured and the room temperature it looks like the system is either running low back pressures from either short of refrigerant or the filter or coil is blocked.You should have about 68 psi back pressure at this room temp.
Suggest looking for leaks or the filter or the system was never fully charged.Fully charge system and the cooling capacity of the unit should increase.
The suction line at the compressor should be sweating back at the compressor when operating correctly.

Nick

[Sir Josiah Sodd]

Hi Aiyub

Suggest looking for leaks or the filter or the system was never fully charged.Fully charge system and the cooling capacity of the unit should increase.

Nice to see you, Nick, and keep posting, but this thread is over 5 years old......!

[Abe]

Yes...........but it brought back memories.

I was in Johannesburg, near University of Witwatersrand
The house belonged to the big boss of Jumbo Cash and Carry....

I left soon after that, so Im not sure what happened......but this guy was so rich he even air conditioned his pantry!!

[nick_nst@aapt.n]

Well then.It's probably fully out of refrigerant by now.
Nick